Taking Australian wetland research to China

jayne_mosquitotrap

My PhD student Jayne Hanford has been super busy this year. Not much more than a year into her candidature and she has already locked away a summer of research and has been presenting her findings at conferences here in Australia as well as overseas.

After recently sharing our research at the Society for Wetland Scientists Annual Conference held in Corpus Christi, Texas, USA and the Mosquito Control Association of Australia conference on the Gold Coast, Jayne is off to China for the 10th INTECOL International Wetlands Conference.

Her research is focused on understanding the links between wetland vegetation, aquatic biodiversity and mosquito populations. Better understanding of these links will assist management strategies that minimise actual and potential pest and public health risks associated with mosquitoes and urban wetlands.

Our abstract for the conference is below:

Is the Biodiversity Value of Constructed Wetlands Linked to their Potential Mosquito-Related Public Health Risks?

Jayne Hanford1, Cameron Webb2, Dieter Hochuli1

1School of Life and Environmental Sciences, The University of Sydney, Australia; 2Department of Medical Entomology, Westmead Hospital and The University of Sydney, Westmead, Australia

 Stormwater treatment wetlands constructed in cities can enhance the sustainability of urban biodiversity by providing wildlife refuge areas and habitat connectivity. However, the creation of wetlands for stormwater infrastructure can increase risks to public health and wellbeing by proliferating nuisance-biting and pathogen-transmitting mosquitoes. In severe cases, this proliferation can erode goodwill in the community for creating and protecting valuable wetland systems.  We compared mosquito assemblages at 24 natural and constructed urban wetlands in the greater Sydney region, Australia. Our aim was to determine if stormwater wetlands constructed with the goal to support high biodiversity value also had reduced associated mosquito risks. Wetlands were located across a gradient of urbanisation determined by surrounding human population density, and included sites with different aquatic and riparian habitat complexity and availability. Adult and larval mosquitoes and aquatic macroinvertebrates were sampled on two occasions through summer and autumn. Aquatic macroinvertebrates were used to derive health indices, as well as being a relative measure of aquatic diversity.  Diversity of adult mosquito species was high, and abundance varied greatly between wetlands. Macroinvertebrate assemblages were also highly variable between sites. Wetlands with greater habitat complexity had lower adult mosquito abundance and greater mosquito species diversity, compared to stormwater-specific wetlands with minimal available habitat. As expected, mosquito assemblages did not respond to urbanisation and aquatic macroinvertebrate assemblages per se, but appeared to respond to a complex suite of coarse and fine-scale features that may affect a wetland’s biodiversity value.  Effectively integrating wetlands into cities requires balancing their design for water infrastructure purposes, biodiversity resources and public health and wellbeing requirements. Understanding the risks as well as the benefits will enhance the value of constructed urban wetlands in sustainable cities while minimising public health risks posed by mosquitoes.

Jayne will be speaking in the “The next generation of wetland science: ecosystems, applications, and engineering” session in the Nanhu Room 1520-1530 on Wednesday 21 September.

You can keep an eye on whats happening in China by following Jayne on Twitter and checking the hashtag

westernsydneywetlands

The Society for Wetland Scientists Annual Conference held in Corpus Christi, Texas, USA back in May included a paper by Jayne titled “Risky Wetlands? Conflicts between biodiversity value and public health” and prompted some great feedback and discussion among wetland scientists at the meeting. It was a successful trip and a timely reminder that I must get to one of the SWS meetings sometime soon, perhaps Puerto Rico?

Keep an eye out for Jayne’s research publications soon!

 

 

 

Moving pictures and managing mosquitoes

Mangroves_Video_June2016

For a few months now I’ve been thinking through some future options for the blog and my science communications activities. I’ve been toying around with starting a podcast or video blog about my work in local wetlands.

#MosquitoWeek has just happened in the U.S. and as it coincided with the close of entries with the Entomological Society of America YouTube competition, I thought what better time to play around with putting together a video.

A year or so ago I had the chance to see Karen McKee (aka The Scientist Videographer) talk about social media and the ways she uses video as a critical component of her community engagement and communications. Since I’m already using Instagram to connect followers with my various wetland sites and mosquito studies (as well as other things), I’ve thought video could be a way to go.

Interesting too since images and video are (or are soon to be) increasingly dominant in social media.

I’m an advocate for mosquito control to be part of overall wetland management. I think I’m sometimes seen as the enemy of wetland and wildlife conservation, not surprising given the perception of mosquito control still influenced by the DDT debate. As we push for the construction and rehabilitation of urban wetlands, the pest and public health risks associated with mosquito populations do need to be considered by local authorities.

I’m often arguing that ecologically sustainable mosquito management is actually critical to wetland conservation. If you’re encouraging the community to visit your wetlands, what happens when they’re chased away by mosquitoes? What about the community living around the wetland? Will nuisance-biting erode the good will of the community for wetland conservation?

You can watch my video, “Why is mosquito management important in our local wetlands?”, at YouTube or below:

You can check out some of my other posts of wetlands, mosquitoes and social media below:

Should we start pulling out mangroves to save our wetlands?

Does wetland rehabilitation need mosquito control?

Can social media help track environmental change?

Mosquitoes, constructed wetlands, urban design and climate change: Some workshop resources

Let me know if you’d be interested in seeing more videos! Send me a tweet.

Should we start pulling out mangroves to save our wetlands?

mangroves_webb_SOPA_November2015

You have no idea how badly I wanted to jump down into the thick black mud.

I don’t remember much about primary school but I do have strong recollections of an assignment on the importance of mangroves to the ecology of the Parramatta River. Perhaps not the assignment itself, but I do remember Mum and Dad taking me down to the river and I drew some pictures of the twists and turns of branches and trunks and the finger-like pneumatophores punching up through the thick dark grey mud. It may only have been 10 minutes drive from home in Western Sydney but it was a glimpse into a world so strange and alluring, how could it not have made an impact on me?

I remember the great disappointment of my parent’s stern words keeping me from jumping down below the high water mark and into the mud. The same feelings of frustration and disappointment when stopped from doing other fun things like playing in stormwater drains, letting off firecrackers or swimming in rips!

Mangroves don’t just attract the attention of young environmental scientists. Exploiting a unique place between the land and sea, mangroves have intrigued and fascinated many before me with the first descriptions, by Greek mariners, thought to date back to 325BC. What were these plants that seemed to defy logic, growing half submerged in salty water?

Almost thirty years after my primary school assignment, with sandshoes replaced by gumboots, that childhood disappointment of adventure squashed is now matched by the realisation that mangroves aren’t perfect. In fact, they’re a threat to some of the other plants and animals found in our local local estuaries.

Now I spend most of my summer coated in that same dark grey mud, covered in mosquito bites and thinking about how important mangrove management will be for the future of our coastal wetlands.

mangroves_duckcreek

More than mangroves

There is little doubt mangroves are an ecologically important habitat. They provide a home for a wide range of creatures, from bacteria to birds. Rich in nutrients and hiding places, mangroves are perfect nurseries for fish and crustaceans. Bird and bats and rodents and reptiles all find a home here too.

They’re threatened by climate change but they may also play a critical role in protecting our shoreline against sea level rise and storm surges. Sea level rise itself may knock out mangrove forests too but mangroves could also mitigate the impacts of climate change by storing carbon. In fact, the role estuarine wetlands may play in keeping carbon dioxide out of the atmosphere could be critical.

Make no mistake, mangroves are important. Thing is, it is also important to also remember that estuarine wetlands are more than just mangroves.

When we talk about estuarine wetlands, we’re grouping together a number of habitats that  include seagrass, saltmarsh, sedgelands and mudflats as well as mangroves. Each of these habitats play an important role in the functioning of the estuary as a whole but they each, individually, provide something specific to the wildlife that utilise the wetlands.

darkmangroves

Saltmarshes are critically important and are in desperate need of conservation. In NSW they’re listed as Endangered Ecological Communities. As well as urbanisation and pollution, a changing climate and sea level rise risk severely degrading the quality of these habitats.

One of the key threats facing saltmarshes is a native plant. A native estuarine wetland plant. Mangroves.

The encroachment of mangroves into saltmashes is a serious problem. This is happening in many parts of the world. It is a strange situation in which one native plant is taking over another and with these ecological shifts, there are knock-on effects to other components of the wetland ecosystem. Most importantly, nesting and feeding shorebirds.

saltmarsh_SOPA

Are mangroves really a threat?

The mangroves are just doing what mangroves do. The reason they’re threatening saltmarshes is due to our modification of local environments.

Urban runoff reduces the salinity of these wetlands and this reduced salinity not only removes the ecological advantages of salt-tolerent saltmarsh plants, such as Sarcocornia quinqueflora and Sporobolus virginicus, but it helps mangrove seeds and seedlings survive the otherwise harsh environmental conditions of saltmarshes. Lower the salinity, increase the invasive potential of mangroves.

Frequent dryness and highly salty conditions are a saltmarsh’s best defense against invading mangroves.

Filling in wetlands and the construction of seawalls, roadways and other infrastructure give saltmarshes little refuge or respite from these threats. While mangroves encroach from the sea, there is nowhere for saltmarshes to migrate to when dealing with sea level rise.

They’re cornered and under attack but even where the plants are persisting, the quality of habitat they provide for local wildlife is slowly degraded by colonising mangrove seedlings.

Blackwingedstilt_henandchickenbay_1september2015

There are many waterbirds that use our local estuaries that are under threat. Saltmarshes are great habitats for migratory shorebirds. There are plentiful resources in the form of insects and other invertebrates within the sediments. The birds can nest on the marsh and as they can see all around, predators are easy to spot. They feel safe.

There have been declines in the White-fronted Chat populations around Sydney. Many other populations of wading birds associated with Australia’s coastal wetlands are in decline too. Mangrove invasion isn’t the only thing to blame but it is an issue that needs to be addressed.

For many of these birds, the encroachment of mangroves into mudflats and saltmarshes is a problem. Its a problem for their foraging and nesting. Once mangrove seedlings start popping up on the middle of the saltmarsh, all those advantages of a wide open habitat in which predators are easy to spot are lost.

Imagine you’re a black-winged stilt. You’re trying to find a safe place to nest. A perfect place would be a raised area of saltmarsh surrounded by water. A dead flat saltmarsh with clear lines of sight for dozens of meters around. You’ll be able to see an approaching predator (like a fox or a feral cat) from far enough way to escape with plenty of time to spare. Now, stick a few mangrove seedlings here and there. They start to obscure your view. They’ll give sneaky predators a place to hide. Even if there are not predators about, you’ll probably get nervous. You’ll probably spend more time thinking about the threat of predators and less time foraging for food.

As mangroves move in, the birds will leave. Long before the saltmarsh is over run by mangroves, out-competed by the shade of establishing young mangroves, the quality of the habitat for many shorebirds will have already been lost. There may be some plants remaining but the ecological role of the habitat is gone.

Parramatta_ConradMartens

Do historic paintings provide conflicting evidence to the commonly held view that mangroves have always been present along the Parramatta River? (Parramatta River, c. 1837, Conrad Martens (1801-78) via Australian Art Auctions)

Painting the picture of change in the local wetlands

How can we predict what will happen in the future if we haven’t learned from the past?

Tracking change in these wetlands is important. The use of photography has played an important role in tracking environmental change for a long time. Aerial photography and satellite imagery have helped reveal dramatic changes in vegetation associated with Australia’s coastal wetlands. This analysis has demonstrated the encroachment of mangroves into saltmarshes and this encroachment is considered a key threatening process of this endangered ecological community.

How can we track the encroachment of mangroves? While technology has helped reveal current changes in mangrove encroachment, other uses of imagery can explore relatively recent “urban myths” about historic mangrove distribution.

Thinking back to that school assignment, I remember being told how important mangroves were to the local environment. We we taught that, here in Sydney, that mangroves were always part of the Parramatta River estuary, that they have alwasy been a critical component of the river’s ecology. Was this really the case?

There has been some brilliant detective work done to determine the historic distribution of mangroves along the Parramatta River in this paper titled “Estuarine wetlands distribution along the Parramatta River, Sydney, 1788–1940: implications for planning and conservation“. The authors have used old photos and, in particular, some of the earliest paintings from the Sydney region (together with notes from settlers at the time) and found that the estuary was dominated by mudflats and saltmarsh habitats and that extensive areas of mangroves did not occur until the 20th Century.

To quote the author, Lynette C. McLoughlin:

“These historical sources indicate that in the 19th century extensive mudflats and saltmarsh communities dominated the inter-tidal zone, with mangroves more limited to creek fringes and some patches in bays for much of the period. In the upper river from Subiaco Creek to Parramatta, there is no evidence for the presence of mangroves until the 1870s. Following settlement and increased sedimentation, inter-tidal mudflats expanded, mangroves colonised up river and out onto mudflats in bays in the latter part of the 19th century, followed by expansion into saltmarsh in the 20th century.”

It is only relatively recently that mangroves have really flourished along the river.

There is absolutely no doubt they were always present, tucked away in the tiny bays and inlets of what became known as Sydney Harbour but it was the mudflats and saltmarshes that dominated much of the estuary. These habitats, no doubt, provided a rich and productive habitat for shorebirds and other wildlife.

mangroves_Dec2015_HenandChickenBay

So, where to from here?

Globally, mangroves are a critical component of wetland ecosystems. There is little doubt of that, and little doubt that in many parts of the world, even here in Australia, they are under threat. But so is saltmarsh and, saltmarsh is far less likely to be given the chance to demonstrate the resilience that mangroves will to continued changed environmental conditions results from a rising sea level and surging urbanisation.

Not just saltmarsh but mudlfats too.

Coastal authorities are increasingly aware of the need to balance protection of mangrove forests and the benefits they provide but also the conservation of saltmarsh and mudflats that are so critical to shorebirds.

The reality is, there will need to be a program of mangrove culling to sustain conservation of saltmarsh habitat. You need a permit to remove mangrove seedlings but a seasonal program of removal would be greatly beneficial in stopped the spread of mangroves into saltmarsh habitats. Local authorities are incorporating mangrove removal programs in their local wetland rehabilitation programs.

Removing young seedlings is easy, you can pull them straight out of the wet mud. Wouldn’t take much to organise a team of volunteers to move through the local saltmarsh removing seedlings. Perhaps in Autumn when the migratory shorebirds have left and the mosquito populations aren’t so bad?

The idea that native vegetation should be actively removed from habitats sounds at odds with environmental conservation. However, we need to maintain our wetlands for our future generations and the next generations of birds, and fish and crustaceans that rely on them now where few other opportunities exist.

mangrove_boardwalk_Jan2016

2 February is World Wetlands Day. Please get out into your local wetlands, or at least make a pledge to visit your nearby wetlands sometime soon.

Learn more about Australia’s amazing mangroves by dropping by MangroveWatch and picking up the excellent Australia’s Mangroves by Norm Duke. There is also an extremely useful text on Australian Saltmarshes that is essential.

Finally, check out one of the most extensive resources on urban wetland management, including estuarine wetlands, via the free eBook produced by the Sydney Olympic Park Authority titled “Workbook for Managing Urban Wetlands in Australia“. Read a brief article on our analysis of the use of this resource in the latest issue of Wetlands Australia, see “Insights from the use of an online wetland management resource” by Webb and Paul (pages 26-27).

What are you doing for World Wetlands Day? Join the conversation on Twitter!

Want to learn more about the amazing world of Australian mosquitoes? Check out “A Field Guide to Mosquitoes of Australia” out now through CSIRO Publishing. Over 200 pages containing a pictorial guide to almost 100 different mosquitoes along with tips on beating their bite and protecting your family from the health risks of mosquitoes. You can order online or through your favourite local bookstore or online retailer.

 

Does wetland rehabilitation need mosquito control?

Webb_estuarinewetlands_SydneyOlympicPark_2014Mosquitoes can be more than a nuisance. They pose health risks but could also erode the good will of the community for wetland rehabilitation projects. Wetland rehabilitation needs mosquito control.

It’s a warm February evening. A small and anxious group of residents have gathered in a local community hall to discuss the implications of a local wetland rehabilitation project. Some are angry. One of the first questions comes from an elderly gentleman. Close to tears, he explains how his grandchildren no longer visit due to the plagues of mosquitoes that engulf his property day and night. “What are you guys going to do about it?” he pleads.

I learnt a valuable lesson that night. Trying to explain the best mosquito repellent to use doesn’t go down too well when an audience is facing some significant nuisance-biting impacts around their homes. It doesn’t matter how much DEET is in the repellent, it may well work but is it something you need to wear all day just to get the day to day jobs done around the house? Something more substantial is required and, with hindsight, should have been in place before the first waves of mosquitoes left the local wetlands.

Coastal wetlands are under threat

Sea level rise and climate change  is putting pressure on saltmarshes and urbanisation is eating away land that would otherwise accommodate a landward shift in estuarine habitats. There is nowhere for saltmarshes to spread to so they’re destined to be swallowed up by mangroves. While the mangroves are valuable themselves, they don’t provide the same critical habitats required by many of the internationally protected migratory shorebirds that rely on saltmarshes. Saltmarsh habitats could well disappear from much of the east coast in coming decades if sea levels rise as expected and mangroves continue their march landward.

webb_landinglightswetlandsEstuarine wetlands and mosquitoes

Saltmarshes are home to one of our most important pest and vector mosquito species. While it is important to remember that Aedes vigilax is an Australian native animal and just as much a part of our wetland ecosystems as fish and birds, there is little doubt that it can have substantial impacts with regard to nuisance-biting and the transmission of Ross River virus.

Historically, many of the saltmarshes along the east coast were drained or filled to enable increased cattle grazing (although much of it was under the guise of protection from flooding). Tidal flows were cut off with the construction of levee banks and installation of flood gates. Notwithstanding the impacts of grazing, without tidal exchange, the habitats became brackish water to freshwater dominated systems with a dramatic change in vegetation. Saltmarsh and sedgeland vegetation was steadily replaced by reeds and rushes. Invasive plants such as Phragmites quickly took over many of these wetlands.

webb_floodgates_march2011Bringing back the tides

To combat the degradation of wetlands and impending loss due to climate change, there has been some ambitious wetland rehabilitation projects planned. One of the largest in the southern hemisphere is the Hexham Swamp Rehabilitation Project. Much can be learned from the experience in this wetland just west of Newcastle, NSW, and applied to rehabilitation projects, not only in Australia but overseas as well.

Rehabilitation of Hexham Swamp involved the staged opening of existing floodgates to reinstall tidal flows to an otherwise freshwater system. Many aspects of this project were considered and it is unsurprising that one major issue was the possible impact of mosquitoes. Mosquito populations were something of legend in this area, enough so that there is a “big mosquito” outside the local bowling club affectionately known as “Ossie the Mossie” (coincidently, “Ossie” celebrated her 20th birthday in March 2014).

One of the important considerations when assessing mosquito risk was that there had been a dramatic transformation of the areas surrounding the wetlands in the last 20 years. What was once agricultural land was now residential. This is the same situation right along the east coast of Australia, the rapid urbanisation and swelling residential populations along the coast have put people in the firing line of Aedes vigilax.

The prospect of mosquito control was raised in the early stages of the rehabilitation planning but there was great reluctance from the local authorities to head down that path. The problem is that broad scale mosquito control and ecological rehabilitation are often seen at opposite ends of the wetland management spectrum. I’ve experienced this many times first hand, from scepticism regarding the non-target impacts of biological larvicides to “Apocalypse Now” jokes as helicopters go about routine spraying of local wetlands.

Webb_MosquitoCollectionsIs there such a thing as “environmentally friendly” mosquito control?

The hangover from the actual and perceived impacts of pesticide use more than 50 years ago is still present in the minds of many responsible for managing local wetlands. I say perceived as the development of environmentally sustainable mosquito control programs over the past two decades may not be appreciated amongst those charged with managing wetlands and wildlife.

I feel we need to continue building the case for the range of mosquito control strategies available for our coastal wetlands. Not only do we need to convince local authorities that mosquito populations can be minimised without adversely impacting the local environment but that mosquito control should be a critical consideration in wetland rehabilitation projects. It also has the potential to reduce mosquito-borne disease.

We know that the direct non-target impacts of Bacillus thuringiensis israelensis and s-methoprene are minimal and there is growing evidence that the indirect impacts on local wildlife due to reduced mosquito populations isn’t a major concern. Well-designed projects can also minimise the frequency of treatments while reducing peaks in mosquito activity.

It seems our coastal bats populations are mostly eating moths, not mosquitoes so there is unlikely to be any significant impact on these bats resulting from reduced food. There is no reason why the judicious use of larvicides can’t knock the top off abundant mosquito populations, reduce the pest impacts on local community and not pose a risk to local wildlife. Perhaps it should be considered a critical component of wetland rehabilitation?

redkneeddoteral_kooragangisland_march2015Mosquito control and wetland rehabilitation

In speaking with wetland managers, I try to instil with them the importance of mosquito control. There is a risk that swarms of nuisance biting mosquitoes may erode the good will in the community for wetland rehabilitation. These systems, particularly in the early phases of rehabilitation don’t represent pristine environments and while there may not be a desire to establish ongoing mosquito control programs, some control may prove useful while the wetland comes back into balance with the changed environmental conditions.

Rehabilitation takes time and while there is substantial breakdown of freshwater vegetation it is not going to be ideal for fish and other mosquito predators. It is likely to provide ideal conditions for mosquitoes. Over time, however, fish are likely to increase in both their abundance and penetration into the wetlands and greater tidal flushing will make many of the wetland habitats generally unsuitable for mosquitoes.

Perhaps there is benefit in undertaking control as a show of good will to the local community? After all, engagement with the local community will be critical in the success of wetland rehabilitation projects.

The restoration of tidal flows to Hexham Swamp resulted in an initial increase in the abundance of Aedes vigilax. These increases resulted in substantial nuisance-biting impacts. However, in subsequent seasons, the populations of Aedes vigilax levelled out to comparable levels to those of the surrounding estuarine wetlands. The net result has generally been that the long-term moderate increases in Aedes vigilax populations have been balanced by reductions in Culex annulirostris and Coquilettidia linealis populations as the wetlands shifted from freshwater to saline. The health of the wetlands, as well as the local estuary, is improving.

Mosquito control is only a short-term fix and if the rehabilitation of estuarine wetlands is not carefully planned, there may well be ongoing mosquito impacts. However, reducing any initial impacts will go a long way to ensuring continued engagement of the community with the local wetlands. Cost and the operational considerations may be a barrier for organisations unfamiliar with broadscale mosquito control but these issues can be overcome with the expertise that exists in many parts of the country.

In summary, it is important that mosquito management be considered in the planning process of major wetland rehabilitation projects. There is little doubt that such projects will be required into the future as saltmarsh habitats and other estuarine wetlands are threatened but protection wetlands shouldn’t mean increasing mosquito populations. A balance is required between conservation of environmental health and protection of human health.

A longer version of this article originally appeared in “Mosquito Bites” (the Bulletin of the Mosquito Control Association of Australia).

The five best non-buggy things about Entomology 2014

portland_oldtownThere was lots of love about Entomology 2014 but some of the biggest highlights had nothing to do with the bugs. Here are some non-entomological hits from the conference.

1. Portland, OR.

Host city makes a difference. I know many considerations are taken into account when deciding on a venue but an interesting host city (or region) can really tip the scales. Portland was a great decision. One of the great things about Portland was that it provided many conversation starters. Tips on where to find the best coffee, craft beer and donuts dominated plenty of on- and offline conversations during the course of the meeting (plus a few “field trips” thrown in for good measure).

I’ve seen interesting/new locations boost the numbers of conference attendees for the Australian Entomological Society and Mosquito Control Association of Australia in recent years too.

bluestardonuts2. Free public transport

Brilliant. With the meeting attracting over 3,000 people, it wasn’t possible to hold the event at a single venue that also provided accommodation for the bulk of attendees. As everyone was spread out across the city, getting back and forth from the Oregon Convention Center could have been quite tricky. Portland has a great public transport network but, better still, conference registrants received a free pass for travel throughout the course of the meeting! It certainly took the stress out of getting around.

sizzlepie3. Promotion of social media

The Entomological Society of America really needs to be congratulated on the way they’re employed social media as a critical component of their scientific conferences. I’ve been to conferences where social media has been tolerated but rarely encouraged. At this meeting, social media use was integrated into the day-to-day conference experience.

There was promotion of #EntSoc14 before, during and after the meeting. From the registration website to the opening address by David Gammel, social media was embraced and encouraged. Probably the best element was the use of a series of large screens throughout the conference center with a cascade of twitter and instagram posts. There was even a large display in the trade hall! Wonderful idea because it brought the “non-tweeting” conference attendees into the mix. I had a few a few conversations with people who don’t use social media but tracked me down because they’d seen tweets on the screen earlier in the meeting.

tweetscreen

An example of the “social media screens” dotted throughout the conference venue (Source: Christie Bahlai ‏@cbahlai)

Having an opportunity to meet in real life many of the wonderful people I’d only ever corresponded with via social media was one fo the highlights of the conference.

I was tempted to post something about tweeting at conference but there are already a bunch of great resources on the use of social media during conferences. Here are just a few “How to live-tweet a conference: A guide for conference organizers and twitter users“, “A Guide to Tweeting at Scientific Meetings for Social Media Veterans” and “Ten Simple Rules of Live Tweeting at Scientific Conferences“.

Here are the key slides (plus a bonus) from my conference presentation on the use of social media to extend the reach of public health messages:

4. Free WiFi

Whether we like it or not, we’re tethered to work. I learned a valuable lesson this year when I took myself “off the grid” for a few weeks during a holiday break. It took me the best part of a month to catch up. Being able to regularly check in with work emails during a conference (without having to pay exorbitant access rates) really helps. It is also handy chasing up papers referenced in presentations and other resources shared throughout the conference.

I know it is no fun seeing a conference room full of people checking email during someone’s presentation and I personally don’t do it myself. However, there were plenty of places and spaces to sit down and do that outside the presentation rooms.

5. A sustainable conference venue

I know this isn’t always possible but having a conference venue that put a high priority on sustainability was great. From recycling of coffee cups to stormwater runoff, most of the bases were covered. Nice for me, given my interest in constructed wetlands and stormwater management, to see the systems in place at the Oregon Conference Center.

Oregonconvention_urbanstormwaterTo some, these may seem like trivial aspects of a major scientific conference but they really made for a great experience at Entomology 2014 for me.

What do you love (or loathe) about scientific conferences (beyond the science itself)? Join the conversation on Twitter.

Can social media help track environmental change?

saltmarshrehabilitation_KGIA picture may well tell a thousand words but what if that picture is tweeted, shared and liked? Could social media help engage the community with local wetlands? Could it assist in crowd sourced tracking of environmental change?

After the fire comes the photos

Using photography to track post-bushfire environmental change is common in Australia where bush fires are a part of life. Scientific publications and technical reports produced across the country have used “before and after” photos to highlight the dramatic change, and equally dramatic recovery, seen in the Australian bush after fire.

How can we incorporate social media in tracking this post-fire recovery? Perhaps it could even play a role in boosting the spirits of the local community seriously impacted by bushfire? The recovery of communities is as important as recovery of the environment. A recent study has highlighted the importance of social networks in the community and perhaps opportunities to share interactions with the environment through social media would provide further opportunities for engagement.

Bushfires are a natural part of the Australian environment and photography plays a key role in reminding us that our vegetation can respond remarkably after even the most intense fires (Source: CSIRO)

Bushfires are a natural part of the Australian environment and photography plays a key role in reminding us that our vegetation can respond remarkably after even the most intense fires (Source: CSIRO)

An example of engaging social media in bushfire recovery comes out of California. I’m particularly taken by the use of social media as a critical component of the program tracking recovery from bush fires that swept through Mt. Diablo in 2011. The project is coordinated by the Nerds for Nature team, inspired by the initiative of Sam Droege and his Monitor Change project.

The idea is based around members of the community taking photos at set locations with set perspectives and compiling those photographs shared through social media, to create a crowd sourced time lapse animations of post-bush fire recovery (you can read a little more about it here). What makes this so neat is the simplicity. Clear signage and a simple bracket for lining up your camera/phone. The website interface is great too. The team behind the project have provided some detailed instructions that form a great basis for adapting this approach to a local environment (they also point out that this project may not be as simple to implement as you may think…).

Tracking bushfire recovery with crowd sourced photographs! (Originally tweeted by Sergei Krupenin in reference to Nerds for Nature program)

An Australian take on crowd sourced “environmental change” photography

Another example of using photography to track environmental change is the Australian Fluker Post project. Similar to the approach by the Nerds for Nature team, this project, coordinated by Dr Martin Fluker at Victoria University, is a “citizen science system designed to allow community members to contribute towards the ongoing care of various natural environments by taking photographs”.

“Fluker Posts” are installed at key locations and members of the community can use their own cameras to take photos and then email them to coordinators. As well as collecting material to assist local land managers, this project may have a more subtle influence on conservation by engaging the community with the local environment. By providing an opportunity for local residents (as well as regular visitors) to track the changes in their local environment, it would be hoped that a connection and care for the local environment would increase. As well as directly changing behaviour that may threaten local habitats or wildlife, the community (and by extension local decision makers) are more likely to be supportive of rehabilitation efforts.

An example of a newly installed Fluker Post ready to help track environmental change (Source: The Fluker Post Project)

An example of a newly installed Fluker Post ready to help track environmental change (Source: The Fluker Post Project)

You can see examples of photos from the various Fluker post locations here but you can also keep up to date with various projects at the Fluker Post Facebook page. A relatively new venture has just kicked off using this “technology” to engage with school students – a great idea!

Tracking tidal changes

Another great example of crowd-sourced tracking of the potential environmental change is the  Witness King Tides program. The program is coordinated by Green Cross Australia and calls of members of the community to submit photos taken during king tide events (the highest of the spring tides each month) to help generate an indication of what may happen in the future with sea level rise. There is a wonderful collection of photo albums here from across Australia.

This idea of a crowd-sourced collection of photographs tracking tidal events has been tried in the past. Most notable was a collection of photos contributed to by over 250 people taken during a major tide event in 2009. A useful document was produced by NSW Office of Environment and Heritage. It highlights an important issue in relation to potential impacts of sea level rise. The first wave of impacts may not be catastrophic but they will be disruptive.

While images of major cities underwater often accompany media reports of rising sea levels and plans for adaptive responses, in many parts of Australia, increasing frequency of these “higher than usual” tides will cause disruption to cities and townships in other ways. Blocking stormwater systems, forcing the closure of roads and delays with ferry services. In addition to this, there is the increasing risk of coastal erosion and loss of amenities in coastal regions.

SOPA_kingtides

“Before and after” shots of a cycleway through Sydney Olympic Park in January 2014. Higher than expected spring tides flooded many of the pathways, cycleways and boardwalks in the local area causing much disruption; perhaps a sign of things to come if rising sea levels make these event more frequent.

One of the problems with this method, however, is that these photographs end up being “one offs”. Without a comparison to “normal” conditions, it can sometimes be difficult to gauge the significance of tidal inundation without being familiar with the local area. Fortunately, there are many examples where contributors send both “before” and “after” tidal inundation shots and they do provide a stunning visual representation of the disruption sea level rise may cause. Perhaps the incorporation of “photography points” (following the examples from the Flucker Post or Nerds For Nature teams) at key locations would be a useful addition to the program?

This approach has been adopted bytThe City of Manduarh in Western Australia with their  Tidal Image Mandurah Project. The community has been asked to take photos at key locations with a view that images of tidal events such as storm surges, high tide and erosion will help track change. Nothing too fancy in these locations either, just a strategically placed spray painted blue camera!

An example of the spray-painted blue camera on a beachside post inviting members of teh community to take and share a photo of Florida Beach (Source City of Mandurah)

An example of the spray-painted blue camera on a beachside post inviting members of the community to take and share a photo of Florida Beach (Source: City of Mandurah)

Tracking constructed wetland change

Where would I like to see this implemented? I’ve had the opportunity to work in and around many newly constructed wetlands. These have ranged from small freshwater wetlands in urban areas to extensive rehabilitated estuarine wetlands. The common denominator across all these sites has been vegetation change. I cannot be out there every week taking photos but it would be great if there was a collection of photos being shared by the local communities that I could tap into.

There are some great examples of interpretive signage around our local wetlands. There is also a shift in thinking from traditional interpretive signage to take advantage of new technologies so why not include social media to engage visitors and local community further? Perhaps social media networking should be included in wetland management plans?

Signage at Gungahlin Wetlands, ACT

Signage at Gungahlin Wetlands, ACT. An example of structures associated with urban wetlands that can be modified to include opportunities for social media use through the use of recommended hashtags (for Twitter or Instagram) and/or brackets for placing cameras/smartphones

A simple addition of a bracket and details on sharing photographs could easily be incorporated into local signage as it is installed and/or updated. As well as tracking changes in vegetation growth in and around constructed and rehabilitated wetlands, the encroachment of mangroves into mudflats or sandy shores along urban estuaries could be a focus too. Of course, storm events and unusually high tides could be documented too. An added bonus would be if some rare or unusual wildlife popped up in photographs.

Educational signage of this nature are common place around wetlands in Sydney, could the inclusion of some guidelines for social sharing images help track mangrove incursion into shoreline habitats?

Educational signage of this nature is common place around wetlands in Sydney, could the inclusion of some guidelines for social sharing images help track mangrove incursion into shoreline habitats?

There are plenty of other ways social media can assist environmental conservation and rehabilitation. Pozible and Landcare have recently announced the launch (and called for the submission of proposals) of a new global crowdfunding partnership called The Landcare Environment Collection, an opportunity to showcase and support the crowdfunding campaigns of environmental groups in Australia and around the world.

Perhaps I need to prepare a proposal for the installation of some “social sharing” camera stands…

Why not join the conversation on Twitter and help share other examples of where social media could help track environmental change.

What do you need to know about West Nile virus?

With the arrival of mosquito season in North America, health authorities have started issuing warnings about prevention of potentially fatal West Nile virus. My latest coauthored publication reviews the epidemiological and clinical aspects of this mosquito-borne pathogen.

West Nile virus is a pathogen generally spread by mosquitoes from birds to humans. While only about one in five people infected develop symptoms (inc fever, headache, body aches, nausea, vomiting, swollen lymph glands or a skin rash.), for those over 50, there can be more serious implications and the illness may be fatal. There is currently no vaccine, avoiding mosquito bites is the only way to prevent disease.

The virus was first detected in North America in 1999 and has since spread from coast to coast, having a significant impact on the health of both people (resulting in an economic burden of around $56 million per year) and wildlife (particularly birds). Interestingly, from 2007 there was a steady decline in the activity of the virus and many thought that major outbreaks would be a thing of the past but 2012 saw a one of the largest outbreaks in almost a decade. During this time, Texas was particularly hard hit with 1,868 cases and estimated costs of around US$47.6 million.

The activity of the virus in 2013 wasn’t insignificant either.

WNV_19992013

Annual total numbers of West Nile virus disease cases and deaths reported by CDC 1999-2013.

It hasn’t only been North America that has been impacted by West Nile virus. Outbreaks of human and animal illness have also been reported in Europe. In fact, cases of West Nile virus were reported from France in the 1960s. However, there wasn’t a major outbreak until 1996-1997; prompting warnings from health authorities about the future risks associated with this pathogen in Europe. The activity of the virus in North American, Europe and Africa provides interesting opportunities to research the genetic differences between regions and potential implications for surveillance and disease control. Europe has developed an extensive surveillance program to assess activity of endemic and exotic mosquitoes and activity of the virus.

Human illness in Europe resulting from West Nile virus infection during 2012 (European Centre for Disease Prevention and Control)

It is interesting to note that one of the key factors linking outbreaks of West Nile virus in both North America and Europe is the presence of closely related mosquitoes. Unlike dengue, chikungunya or yellow fever viruses that are spread by Aedes mosquitoes, and malaria parasites by Anopheles mosquitoes, West Nile virus is primarily spread by Culex mosquitoes. In particular, the bird-feeding mosquitoes within the Culex pipiens group.

The Culex pipiens group, particularly Culex pipiens, Culex quinquefasciatus and Culex molestus, are closely associated with urban environments. With mosquitoes found in close contact with humans, there is greater risk associated with potential outbreaks.

Our recent review article in the International Journal of General Medicine provides an overview of the clinical and epidemiological aspects of West Nile virus and is a good starting point for anyone interested in this pathogen and the factors that drive outbreaks in North America and Europe.

The abstract of our paper is here:

The reurgence of West Nile virus (WNV) in North America and Europe in recent years has raised the concerns of local authorities and highlighted that mosquito-borne disease is not restricted to tropical regions of the world. WNV is maintained in enzootic cycles involving, primarily, Culex spp. mosquitoes and avian hosts, with epizootic spread to mammals, including horses and humans. Human infection results in symptomatic illness in approximately one-fifth of cases and neuroinvasive disease in less than 1% of infected persons. The most consistently recognized risk factor for neuroinvasive disease is older age, although diabetes mellitus, alcohol excess, and a history of cancer may also increase risk. Despite the increasing public health concern, the current WNV treatments are inadequate. Current evidence supporting the use of ribavirin, interferon α, and WNV-specific immunoglobulin are reviewed. Nucleic acid detection has been an important diagnostic development, which is particularly important for the protection of the donated blood supply. While effective WNV vaccines are widely available for horses, no human vaccine has been registered. Uncertainty surrounds the magnitude of future risk posed by WNV, and predictive models are limited by the heterogeneity of environmental, vector, and host factors, even in neighboring regions. However, recent history has demonstrated that for regions where suitable mosquito vectors and reservoir hosts are present, there will be a risk of major epidemics. Given the potential for these outbreaks to include severe neuroinvasive disease, strategies should be implemented to monitor for, and respond to, outbreak risk. While broadscale mosquito control programs will assist in reducing the abundance of mosquito populations and subsequently reduce the risks of disease, for many individuals, the use of topical insect repellents and other personal protective strategies will remain the first line of defense against infection.

The full paper can be downloaded for free here.

You can also read more background to West Nile virus and the 2012 outbreak in my piece for The Conversation. For a comprehensive look at how the pathogen is managed in North America, download the CDC publication “West Nile Virus in the United States: Guidelines for Surveillance, Prevention, and Control“.

Why not join the conversation on Twitter by following me at @mozziebites?

The image at the top of this piece is taken from Mother Jones.

Why is mosquito-borne disease risk greater in autumn?

Repel_illustration_DSMosquito-borne disease risk in Australia is greatest during summer right? Wrong. Imagine you’re heading off to football training for the first time this season. Training kicks off in mid-March ahead of an April start to the season. Training is once a week, typically at dusk. Playing fields are located close to wetlands. There mozzies aren’t as bad as they were back in January so why put on insect repellent? The reality is you are more likely to catch Ross River virus during autumn. Recent health warnings confirm it. Why?

The most common mosquito-borne disease in Australia is caused by Ross River virus. Infection can cause symptoms that can be highly variable in their severity but may include  rash, fever, fatigue as well as arthritic pain. Disease caused by infection with this mosquito-borne virus is reported in over 4,000 people each year from across the country.

Can we predict outbreaks of Ross River virus?

Predicting outbreaks of Ross River virus can be difficult. There are differing drivers of outbreaks between both regions and season. While outbreaks typically occur when mosquito populations are high, abundant mosquito populations don’t guarantee an outbreak of disease. Similarly, outbreaks can still occur when mosquito populations are low. The reasons for this are complex.

Perhaps most importantly, mosquitoes don’t emerge from the wetlands infected with Ross River virus, they must bite an infected animal first. The animals most likely to pass the virus onto mosquitoes are kangaroos and wallabies (waterbirds are most likely to be involved in the transmission cycles of other Australian mosquito-borne viruses such as Murray Valley encephalitis virus). This means that, despite the relative abundance of mosquitoes, without the presence of kangaroos and wallabies, the risks of Ross River virus transmission are low. This is why Ross River virus is generally considered a rural disease. However, there have been small outbreaks in metropolitan Sydney where kangaroos and wallabies are present. Outbreaks will almost always required the presence of macropods.

mosquitoes_undermicroscopeWhat has been happening in 2014?

There has been plenty of activity of Ross River virus in coastal NSW this year, particularly around the Georges River region of Sydney. This is one of my key study sites and provides a good opportunity to study Ross River virus in a region where mosquitoes, wildlife, wetlands and people are all present. The detection of Ross River virus, along with Barmah Forest virus and Stratford virus, in mosquitoes in the suburbs of Lugarno, Alfords Point, Illawong and Bankstown in early 2014 has prompted warnings from local health authorities. Similarly, Ross River virus has been isolated from mosquitoes in the Newcastle/Port Stephens region, also prompting the release of health warnings. So too around Port Macquarie. There were plenty of mosquitoes about in summer but why are the risks comparatively much higher in autumn?

georgesriversharks

Sharks may patrol the waters of Georges River but mosquitoes rule the wetlands. When it comes to mosquito-borne disease risk, it is the swamp wallabies that really raise the risks.

Why are there more Ross River virus cases in autumn?

Remember when I posted the question back in January 2014… “could the Autumn of 2014 see a surge in cases of disease?” When national notification data for Ross River virus infections are reviewed, there is a distinct peak in cases around March. With regard to overall seasonal averages, there are more cases in the three months of autumn than those of summer. In part, the official statistics may reflect a delay between initial infection of an individual and the collection of official statistics but there are also other factors at play.

MonthlyRRV

Average monthly notifications of Ross River virus across Australia between 1992-2013 (National Notifiable Diseases Surveillance System)

What may be some of the driving factors in the autumn peak of disease notifications?

  1. It takes time for the pathogens to circulate amongst animals and mosquitoes. We don’t exactly know what kick starts outbreaks of Ross River virus. Is the virus present at very low levels all the time, only to explode when conditions are right or is it introduced by an animal or travelling human? Either way, it may take time for the pathogens to spread amongst local wildlife and, subsequently, sufficient numbers of mosquitoes becoming infected to drive increases in human disease notifications.
  2. Diversity of mosquito populations. While the abundance of estuarine mosquitoes (such as Aedes vigilax), and those associated with ephemeral habitats, will tend to go up and down over the summer and autumn, freshwater mosquitoes like Culex annulirostris will tend to build in their abundance from mid-summer through until autumn. These mosquitoes have been identified as key to outbreaks of Ross River virus. Perhaps it is the overall diversity, rather than abundance of a particular mosquito species that is important?
  3. Mosquitoes are living longer. As mentioned earlier, mosquitoes must bite an infected animal to become infective themselves. The longer a mosquito lives, the more likely it is to acquire an infected bloodmeal from a wallaby or kangaroo and then more likely to pass it on to one or more people. Like all insects, the mortality of mosquitoes is influenced by climate. Mosquitoes live longer during the cooler and, generally, more humid conditions in autumn than the hot and dry summer.
  4. We’re getting complacent. It may have been a long hot summer full of mosquitoes. Back in January you may have been chased out of the local wetlands due to the number of mosquitoes. As the intensity of nuisance-biting declines, most people are probably increasingly likely to skip the application of insect repellents or be vigilant about mosquito bites. Similarly, we’re probably less likely to apply a sunscreen in cooler months. I’ve worked with local health authorities to coordinate public health messages ahead of the Easter long weekend. I’ve often thought that this is a time when many head off on a camping weekend and may not be thinking about mozzies. Fortunately, in 2014, the Easter holiday falls towards the end of April, greatly reducing the risks when compared to early April holidays.
  5. More people are being tested in autumn. There is probably not an even spread of awareness of mosquito-borne disease amongst health professionals. Recently, my GP told me I’m the only person he’s ever requested a Barmah Forest virus test for (just routine testing for me). I live in a very low risk region but I’m only a 20min drive from a region currently experiencing Ross River virus and Barmah Forest virus activity amongst mosquito populations. When there are outbreaks, or when there is media coverage of Ross River virus activity, GPs and the community will be more aware of potential disease and perhaps may be more willing to request tests. This awareness is likely to build over the summer and into autumn so that, perhaps, more people are being tested in autumn than summer.

How does this influence public health messages?

While working for the Living with Mosquitoes group in the Hunter region, we discussed many different ways to increase awareness of mosquito-borne disease within the region. As well as developing a range of different approaches to raising awareness amongst the community, it was suggested that perhaps a local sports person could become a spokesperson for a television campaign. What sports person would you choose? A cricketer obviously right? Perhaps it should be a footballer given their considerably higher profile at this time of the year?

Should a NRL player, rather than summer sports star, be the face of a mosquito-borne disease awareness? (Photo: Sharks)

For me, I’m always trying to think of groups in the community that may be at higher risks or activities that may hold greater potential for exposure to mosquito bites. Bushwalking, camping and fishing are obvious cases in point. This was one of the reasons why we developed “mosquito risk tide charts” for a couple of years back, highlighting periods of the summer when mosquitoes were most likely to be in high abundance (as well as providing some general advice on mosquito repellents and other personal protection strategies).

The autumn peak in Ross River virus risk is always a consideration ahead of Easter holidays. This year, we’re fortunate in that the long weekend falls in mid-late April so the risks may be less had Easter fallen at the end of March or early April. Nonetheless, it is always important to spread the word as Australian’s head off for a weekend of camping. Make sure you’ve packed the repellent!

Lastly, I’ve been thinking back to the start of the football season. I’ve seen plenty of people out training hard throughout March in the lead up to the stat of the season. You may be less likely to be bitten by mozzies while actually running about but how about down down and the coaches, support staff and parents standing about. I must stress that there is no evidence from the human notification data that football training is resulting in increased numbers of cases but I wonder if this is a group of people to whom public health messages could be directed. They are typically a well connected group of people with good lines of communications, perhaps a reminder at the start of the football season about mosquito repellent use would be handy?

UPDATE [11 April 2014] NSW and Victorian Health authorities have issued new health warnings to avoid mosquito bites during the school holidays and Easter long weekend following the detection of the potentially fatal Murray Valley encephalitis virus in sentinel chicken flocks in the Riverina region. Other mosquito-borne viruses including Ross River and Barmah Forest viruses continue to be detected in mosquito populations collected along the coast. Current understandings of the more serious Murray Valley encephalitis virus and Kunjin virus are not thought to be active in coastal regions of NSW and SE QLD.

Why not join the conversation on Twitter by following me at @mozziebites?

The illustration at the top of this piece comes from the 1943 booklet “This is Ann – She’s dying to meet you” by the US War Department. Recognise the work of a very famous illustrator?

 

Mosquitoes, constructed wetlands, urban design and climate change: Some workshop resources

wetlandswalkThis is a short summary of resources supporting my lecture on “Mosquito Management, Climate Change and Urban Design” at Environmental Health Association of NSW Public Health School on Monday 24 March 2014, Sydney Olympic Park.

The nuisance-biting and potential transmission of pathogens by mosquitoes in coastal Australia is a concern for local authorities. Increasingly so at the fringes of our cities. There has been something of a resurgence in Ross River virus this year with the virus isolated from mosquitoes collected at a number of locations across NSW.

While it is difficult to determine exactly why this resurgence has been experienced this year, there are a number of factors that can predispose a region to elevated risk. An understanding of local risks are important and regionally specific mosquito management plans (i.e. the “Living with Mosquitoes” strategies) have been developed in the Hunter and Mid North Coast as well as the Central Coast regions of NSW. These documents provide an overview of mosquito fauna, identify key pest and vector species and their associated habitats and respective environmental drivers of abundance. With the provision of information on mosquito management strategies, local authorities can develop regionally specific responses to seasonal pest and public health risks.

wetlands_sydneyparkAs well as providing strategies for local authorities on mosquito control activities, they also provide opportunities to shape future mosquito-borne disease risk through urban design. While efforts are underway to better manage urban water conservation through Water Sensitive Urban Design, perhaps “Mosquito Aware urban Design” should also become an important component of new residential developments? There appears to be growing evidence that how we manage water in our cities will have just as great an impact of future mosquito-borne disease risk as climate change.

Despite the claims that often accompany discussion of the health impacts of climate change, Australia is unlikely to see a dramatic increase in “exotic” mosquito-borne disease. There may be regional increases in Ross River virus and Barmah Forest virus with changes in rainfall, temperature, extreme weather events and sea level rise but, equally, some regions may see a decrease. Understanding the complex interactions between mosquitoes, wetlands, wildlife and pathogens is required to fully understand these “endemic” risks. Perhaps with regard to “exotic” risks associated with viruses such as dengue and chikungunya, it will be the introduction of exotic mosquitoes, such as the Asian Tiger Mosquito, Aedes albopictus, that will pose the greatest risk.

Monitoring mosquitoes and the pathogens they're carrying will remain critical in assisting the assessment and management of public health risks in Australia

Monitoring mosquitoes and the pathogens they’re carrying will remain critical in assisting the assessment and management of public health risks in Australia

There are many things Environmental Health Officers with local council or health authorities will need to consider when assessing local mosquito risks but the basis for all their decisions should come from a well designed and resources surveillance program. There are new technologies available for both the collection of mosquitoes as well as detection of pathogens. However, an understanding of regionally important pathogens, mosquitoes and their local habitats is critical.

The slides of my presentation are below:

 

Some key resources were included in the presentation and are linked to below.

For guidelines on the risk assessment of potential mosquitoes and mosquito-borne disease associated with constructed wetlands in western Sydney, see this document developed by Western Sydney Local Health District Byun & Webb – Guidelines for mosquito risk assessment and management in constructed wetlands – WSLHD – Nov 2012

There are two chapters contained within the recent eBook (free to download) “Workbook for Managing Urban Wetlands in Australia” that provide an understanding of mosquito and mosquito-borne disease risk more generally in association with freshwater constructed wetlands and estuarine rehabilitated wetlands.

 

 

Anticipating infectious threats to Australia

What are the human, agricultural, wildlife and entomological infectious disease threats to Australia? To answer this questions, the University of Sydney’s Marie Bashir Institute of Infectious Diseases and Biosecurity co-ordinated a “collective brainstorm” session to map out the way forward in assessing and address these future risks.

Moderated by Professor Eddie Holmes, the session included “five top leaders in their respective fields” to provide an overview and discuss recent advances, as well as determining the key challenges with discussion amongst attendees. A fascinating collection of topics and I was fortunate enough to be invited to contribute my knowledge on mosquito-borne disease threats in the Australia region.

Professor Jon Iredell spoke about the development of antibiotic resistance in human pathogens. Most interestingly, he touched on the role humans play in exposing our environment and wildlife to these antibiotics and the resulting impacts on the broader community. Although the issue of antibiotics hasn’t touched my work directly, I’m aware of this issue in relation to the role of constructed wetlands associated with agricultural and urban wastewater facilities. Notwithstanding the direct human health issues, interaction with wildlife may have implications for emerging zoonotic pathogens.

Professor Robert Park spoke about agricultural disease. A fascinating presentation on a topic I wasn’t familiar with but was surprised as to the relevance to exotic vector-borne pathogens. Robert spoke about the Australian Cereal Rust Control Program and how it plays an important role in monitoring the incursions of this fungi.

Dr Karrie Rose spoke about wildlife disease and highlighted some of the issues surrounding the investigation of outbreaks where the environmental, agricultural or human health issues may not be clear from the outset. Additional issues surround the diagnosis of these pathogens and determining the authorities responsible for the outbreak. Karie is the manager of the Australian Registry of Wildlife Health, a program of Taronga Conservation Society Australia and provided a great overview of the diverse nature of zoonotic pathogens, from Chytrid fungus to orbivirus, local authorities must deal with.

Monitoring mosquitoes and the pathogens they're carrying will remain critical in assisting the assessment and management of public health risks in Australia

Monitoring mosquitoes and the pathogens they’re carrying will remain critical in assisting the assessment and management of public health risks in Australia

I spoke about the endemic and exotic mosquito-borne disease threats to Australia, from Ross River virus to dengue. My presentation highlighted issues surrounding globalisation, urbanisation and a changing climate with particular emphasis on the potential introduction of the Asian Tiger Mosquito to mainland Australia and the recent increase in Australian travellers returning home with dengue and chikungunya virus infections. Analysis by WA Health authorities have highlighted the increased risk associated with travel to Bali in recent years. There have also been cases of “airport” or “baggage” dengue, including the first locally acquired cases of dengue in WA for over 70 years as well as a case of infection under similar circumstances near Darwin. The Darwin case was also reported in this PLOS NTD paper. At a time when FNQ is experiencing multiple outbreaks of dengue, there seems to be ever increasing opportunities for the pathogens and vectors to be entering mainland Australia.

You can catch up on the slides from my presentation below:

and a collection of tweets from the session collated by @MarieBashirInst is here.

[The photo at the top of this post is taken from the CDC]