Global Health Security 2019 – Mosquito threats and community engagement

Webb_GHS2019

While we can embrace technology to track pathogens and diseases, engaging the community to be more aware of the risk and the ways to avoid them will be critical in reducing the public health burden across the globe. This was a key message repeated again and again throughout the sessions at the inaugural Global Health Security conference in Sydney.

The event around 800 delegates representing academia, local, national and international governmental and non-governmental organizations, public and animal health and security professionals, and the private sector. There were representatives from over 65 countries.

I had the opportunity to contribute in a couple of sessions, firstly the ‘Emerging Infectious Diseases in a Changing Global Environment’ workshop at the university of Sydney. This was co-presented by the Marie Bashir Institute for Infectious Diseases and Biosecurity and CREID – NHMRC Centre of Research Excellence in Emerging Infectious Disease. It was described as an “event is an opportunity for policy makers, public health and clinical researchers, veterinarians, scientists, and WHO representatives to come together and define the health security issues related to emerging infectious diseases (EIDs) and antimicrobial resistance (AMR) in the Asia-Pacific region.”

I spoke about mosquitoes in Australian cities and the challenges facing the management of issues associated with urban planning, constructed and rehabilitated wetlands, endemic mosquito-borne disease risk, and exotic mosquito threats. A little nervous having the Chief Medical Officer of Australia (Prof Brendan Murphy) in the front row, along with representatives of WHO and CDC but a wonderful opportunity to share my research and perspectives on these local issues.

The following day, I spoke in the “Challenges with Zoonotic Diseases” session alongside Elpidius Rukambile and Berihun Afera Tadele. An interesting session (chaired by Siobhan Mor) that, through the panel discussion, highlighted the importance of community engagement, as well as communications between policy makers and those “on the ground” in improving public health outcomes in the “one health” space.

I spoke about the issues surrounding exotic mosquito threats in Australia with a focus on the results of recent work on the far north coast of NSW. The work we did there highlighted the need for cooperation between all levels of government but also the critical importance of engaging the local community. Notwithstanding the effort required to go from property to property searching for introduced mosquitoes, such as Aedes aegypti or Aedes albopictus, understanding the role of the community in this response provided essential. Successful local eradication of any introduced mosquito will require assistance from the local community.

The abstract of my presentation is below:

Building capacity to address the unexpected challenges associated with the emerging threat of exotic mosquitoes in Australia

Webb C (1,2),  Doggett S (2), Piazza K (3), McNicoll D (3), Sly A (4), Neilson J (4), Dean A (5), Bethmont A (6).

1 University Of Sydney, Westmead NSW, Australia; 2 NSW Health Pathology, Westmead NSW, Australia; 3 Tweed Shire Council, Tweed Heads NSW, Australia; 4 Department of Agriculture and Water Resources, Canberra ACT, Australia; 5 University of Queensland, Brisbane QLD, Australia; 6 NSW Health, North Sydney NSW, Australia

Introduction. Ongoing evolution of trade pathways increases the risk of exotic mosquitoes, especially Aedes albopictus and pesticide resistant Ae. aegypti, establishing or expanding their range in Australia. This highlights the need for health authorities to develop strategic response plans considering different risk scenarios. Context and Aim. Key challenges to exotic mosquito response in Australian include capacity at local government level and community acceptance of measures. Several strategic initiatives were used to study these challenges in the NSW Northern Rivers region. Method. Field exercises were undertaken with representatives of 11 local and state authority stakeholders, surveying approximately 300 residential properties for potential mosquito habitats. A survey of community attitudes to mosquito threats and responses was also conducted, with over 700 responses collected. Findings. Surveys found almost 4,000 actual and potential container breeding sites, demonstrating potential for exotic mosquito establishment and subsequent need to manage local transmission risks of pathogens including dengue, chikungunya and Zika viruses. Surveys of community attitudes found significant community resistance to required mosquito control activities, indicating responses would be challenging and need strategic planning. Innovative contribution to policy and practice. Strategic response plans must address mosquito biology but also not underestimate the need for active community engagement.

Overall, it was a wonderful meeting. It was, however, unfortunate that I couldn’t spend as much time in sessions as I would have liked. There were plenty of tweets so check in on the hashtag #GHS2019. There is also the very important “The Sydney Statement on Global Health Security” to come out of the meeting, please check it out.

Were you at the meeting? What did you think? Join the conversation on Twitter.

 

 

Can citizen science help stop mosquito-borne disease outbreaks?

Aedesaegypti_Westmead_Webb

Mosquito surveillance has been a critical component of how health authorities manage the risk of mosquito-borne disease. Data on the abundance and diversity of mosquitoes, together with activity of mosquito-borne pathogens, can guide decisions on when and how to apply mosquito control agents or issue public health warnings.

Almost every state and territory in Australia conducts seasonal mosquito surveillance. The exceptions are Tasmania and ACT, although both have had some limited investigations over the years. Even among those doing routine surveillance, the program structure varies but most include the collection of mosquitoes. This is how we can determine if it really is “the worst mosquito season ever”!

The programs are currently are working well in providing early warnings of outbreaks of mosquito-borne disease. These programs often include mosquito trapping undertaken by local governments and, occasionally, members of the public. For may years there has been a strong interest in citizen scientists undertaking mosquito sampling, particularly by some schools. The projects that I’ve been involved with have rarely got off the ground for various reasons. School holidays at the peak of mosquito season doesn’t help. Beyond that, the consumable costs of the traps we use, especially the dry-ice (carbon dioxide) used to bait the traps, can be a barrier to involvement. Dry-ice use in schools, and the associated health and safety issues, has been a cause for concern too. Finally, the fact that mosquitoes may be attracted to traps operated in school or community grounds and that these mosquitoes may be carrying disease-causing pathogens can often raise concerns.

As a result, there really haven’t been any major citizen science based mosquito surveillance programs until recently. Things are changing.

One reason local authorities are starting to turn their minds to a citizen science based approach is that the threat of exotic mosquitoes will require a shift in focus from the swamps to the suburbs. The mosquitoes that drive outbreaks of dengue, particularly Aedes aegypti and Aedes albopictus live in water-holding containers in backyards and populations are not as easily measured by traditional surveillance approaches. This is why there has been a much stronger engagement with the public in Far North QLD (a region where Aedes aegypti is present and causes occasional outbreaks of dengue) where health authorities are regularly visiting backyards looking for and controlling backyard mosquitoes

There are many reasons why citizen science is starting to come into play when it comes to mosquito surveillance more broadly. Technology is getting better (as highlighted by many smartphone apps) but also, some of the laboratory techniques are getting cheaper. This is a really critical issue.

A breakthrough in rapid testing of mosquitoes led to the development of an award winning initiative in Brisbane by Metro South Health and Queensland Health Forensic & Scientific Services. The Zika Mozzie Seeker project combines this new laboratory technique with DIY mosquito traps by the general public to help track exotic mosquitoes. In short, residents create their own mosquito trap out of a bucket or recycled plastic container, it is filled with water and placed in a yard with a small piece of paper hung inside. Mosquitoes then drop by to lay eggs on the paper. After a couple of weeks, the traps are collected and egg filled paper strips sent to the lab and tested to track the DNA of local and exotic mosquitoes. The project has been an amazing success with around 2,000 participants being involved in recent years (that adds up to about 150,000 mosquito eggs collected and tested). Luckily, no exotic mosquitoes have been detected.

But when it comes to citizen science based projects, perhaps it isn’t the mosquitoes collected (the backyard mosquito battles are fun to track though) but the awareness raised that is important. Awareness not only of the risks posed by mosquitoes, but what you can do about them through the safe and effective use of mosquito repellents and other personal protection measures. Engaging the public through citizen science may be the way to go. It doesn’t always work in reaching new audiences, as was discovered in a mosquito surveillance project in South Australia, but that doesn’t mean it won’t!

Perhaps the rise in new smartphone apps will help. There are a few out there, like the Globe Observer and Mosquito Alert. These, and other smartphone apps, deserve their own post (stay tuned). However, the significant initiative of recent years has been the Global Mosquito Alert project. Launched in May 2017, here is an extract from their media release:

The new initiative, launched under the name ‘Global Mosquito Alert’, brings together thousands of scientists and volunteers from around the world to track and control mosquito borne viruses, including Zika, yellow fever, chikungunya, dengue, malaria and the West Nile virus. It is the first global platform dedicated to citizen science techniques to tackle the monitoring of mosquito populations. The programme is expected to move forward as a collaboration involving the European, Australian and American Citizen Science Associations as well as the developing citizen science community in Southeast Asia.

With such momentum, it is an exciting time to consider the potential of citizen science in Australian mosquito surveillance programs. This is what i will be exploring in my presentation at the Australian Citizen Science Conference in Adelaide this week.

I’ll be presenting the paper on Wednesday 7 February 2018 in the “Empower with Data” session. The full abstract of our presentation is below:

The public as a partner in enhancing mosquito surveillance networks to protect public health

Craig Williams (1), Brian L. Montgomery (2), Phil Rocha (2), and Cameron Webb (3)

(1) University of South Australia, School of Pharmacy and Medical Sciences; (2) Metro South Public Health Unit, Queensland Health; (3) Medical Entomology, Marie Bashir Institute of Infectious Diseases and Biosecurity, University of Sydney

Mosquito-borne diseases are pervasive public health concerns on a global scale. Strategic management of risk requires well-designed surveillance programs, typically coordinated by local health authorities, for both endemic and exotic mosquitoes as well as the pathogens that they may transmit. There is great potential to utilise citizen science to expand the reach of current surveillance programs, particularly those centred on urban areas. There is increasing focus internationally on the role of citizen science in mosquito surveillance as evidenced by the establishment of the ‘Global Mosquito Alert’ project driven by multiple international stakeholders and citizen science associations. In Australia, new initiatives to engage the public in mosquito surveillance are emerging in multiple centres; utilizing a range of emerging field and laboratory technologies that remove previously existing barriers to community involvement. In South Australia, citizen science entomology programs have been trialed, and mosquito trapping and identification technology to expand existing trapping networks has been assessed. In suburban South-East Queensland, Zika Mozzie Seeker is linking citizen scientists into a network by using new laboratory techniques to rapidly screen for Ae. aegypti DNA in large numbers of eggs collected from DIY ovitraps,. In NSW, citizen science is being used to promote biodiversity and delineate pest and non-pest activity of mosquitoes associated with urban wetlands and surrounding suburbs. Citizen science holds great potential for public engagement activities as well as serving to enhance existing surveillance operations.

 

Join the conversation on Twitter by following Dr Cameron Webb, A/Prof Craig Williams and keep an eye on the meeting via the hashtag

A Guam visit to battle Zika virus and discover new mosquitoes

Guam2017_Beach

There are few places on earth where you can search in water-filled canoes for one of the most dangerous mosquitoes on the planet less than a stone’s throw from tourists posing for selfies alongside their inflatable novelty swans in the nearby lagoon.

Guam is the place to go if you need to tick that off your “to do” list!

I was fortunate to be invited to speak at the Pacific Island Health Officers Association (PIHOA) Regional Zika Summit and Vector Control Workshop in Guam 25-29 June 2017. The theme of the summit was “Break Down the Silos for Preparedness and Management of Emergencies and Disasters in United States Affiliated Islands” and had objectives to critical analyze the regional responses to recent mosquito-borne disease outbreaks while developing policies to strengthening public health emergency response and preparedness systems and capabilities within the region.

The tranquil lagoons of the Pacific Islands may seem a very long way from the hustle and bustle of the busy South American cities that held the 2016 Olympics but just as Zika virus was grabbing the attention of sports reporters everywhere, health authorities active in the Pacific were growing concerned too.

Guam2017_StormClouds

The Pacific has been far from free of mosquito-borne disease outbreaks. Previous outbreaks of dengue, chikungunya and even Ross River virus had struck numerous times. While sometimes widespread, at other times outbreaks were more sporadic or isolated. As is the case for many non-endemic countries, outbreaks are prompted by movement of infected travelers and the prevalence of local mosquitoes.

Across the region there are four mosquitoes of primary concern, Aedes aegypti, Aedes albopictus, Aedes polynesiensis and Aedes hensilli. The greatest concerns are associated with Aedes aegypti and in those countries where the mosquito is present, the risks of mosquito-borne disease outbreak are greatest. For this reason alone, it is imperative that good entomological surveillance data is collected to confirm the distribution of these mosquitoes but also to develop strategies to eradicate, where possible, Aedes aegypti should it be introduced to new jurisdictions.

With a growing interest in developing mosquito surveillance and control programs for exotic mosquitoes here in Australia, it was a perfect opportunity for me to get a closer look at how the threats of these mosquitoes and associated outbreaks of disease are managed.

On the third day of the meeting, vector control took centre stage. A brilliant day of talks from each of the jurisdictions on the disease outbreaks they’ve faced and how they’re preparing for future threats. There were presentations from the United States Affiliated Pacific Islands (USAPI) including Guam, the Federated States of Micronesia (Yap, Kosrea, Chuuk, Pohnpei), the Commonwealth of the Northern Marianas (CNMI), the Republic of Palau, the Republic of Marshall Islands (RMI), and American Samoa.

Hearing from these teams doing their best to protect their local communities from the threat of mosquito-borne disease, with only limited resources, was quite eye opening. There was passion and dedication but each territory faced unique challenges to ensure the burden of disease is minimised.

Guam2017_Canoe

Just outside the workshop venue were a series of water-filled canoes. Most contained larvae!

There is little doubt that climate variability will have a strong role to play in the impacts of mosquito-borne disease across the region in the future but there are so many other issues that could be contributing to increased risk too. One of the biggest problems is rubbish.

Time and time again, the issue of accumulated waste, especially car bodies and discarded tyres, was raised as a major problem. As many of the key pest mosquitoes love these objects that trap water, treatment of these increasing stockpiles becomes more of a concern. Community wide cleanups can help reduce the sources of many mosquitoes but the rubbish more often than not remains on the island and requires continued management to ensure is not becoming a home to millions of mosquitoes.

It is a reminder that successful mosquito control relies on much more than just insecticides. An integrated approach is critical.

There was a “hands on” session of surveillance and control. Coordinated by PIHOA’s Eileen Jefferies and Elodie Vajda, the workshop was a great success. It provided an opportunity for many to see how to prepare ovitraps and BGS traps (one of the most widely used mosquito traps) and discuss the various considerations for choosing and using the right insecticides to reduce mosquito-borne disease risk. Workshop attendees were also the luck recipients of a selection of cleaver public awareness material produced in Guam, from personal fans and anatomically incorrect plush mosquitoes to Frisbees and mosquito-themes Pokemon cards!

Guam2017_EntomologyandEnvironmentalHealth

Guam “mozzie” team: Elodie Vajda, Claire Baradi, Michelle Lastimoza, Eileen Jefferies and me

Following the summit, there was a chance to visit the new Guam “Mosquito Laboratory”, newly established as part of the Guam Environmental Public Health Laboratory (GEPHL). I’ll go out of my way to visit any mosquito laboratory but I was particularly keen to see this one as one of my previous students was playing a key role in establishing the mosquito rearing and identification laboratories. Elodie has been doing an amazing job and it was brilliant to geek out with her over some hard core mosquito taxomony as we tried to ID a couple of tricky specimens. [Make sure you check out our recent paper on the potential impact of climate change on malaria outbreaks in Ethiopia]

It actually turned out that one of their “tricky specimens” was a new species record for Guam – an exotic mosquito Wyeomyia mitchellii! The paper reporting this finding has just been published “New Record of Wyeomyia mitchellii (Diptera: Culicidae) on Guam, United States“.

Guam2017_SpeciesList

Mosquito-borne disease in the Pacific isn’t going anywhere and it’s important that once the focus fades from Zika virus, dengue and chikungunya viruses will again take centre stage and their potential impacts are significant. With the added risks that come with gaps in the understanding of local pest and vector species, the prevalence of insecticide resistance among local mosquitoes, climate variability and a struggle to secure adequate funding, challenges lay ahead in ensuring the burden of mosquito-borne disease doesn’t increase.

A modified version of this article appears in the latest issue (Winter 2017; 12(1)) of Mosquito Bites Magazine, (a publication of the Mosquito Control Association of Australia)

 

Talking wetlands, wildlife and mosquitoes at the 2017 Australian Entomological Society Meeting

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I’ll be in Terrigal, on the NSW Central Coast, for the 2017 Australian Entomological Society conference and taking the opportunity to present a summary of a number of collaborative projects undertaken in recent years, from working out how surrounding landuse influences the mosquito populations in urban mangroves to how important mosquitoes are to the diet of local bats.

Together with a range of colleagues, I’ve been undertaking research into the factors driving mosquito and mosquito-borne disease risk in urban wetlands. It is a complex puzzle to solve with more than just mosquitoes determining local pest and public health risks. However, with outbreaks of mosquito-borne Ross River virus on the rise in recent years, including urban areas of Australia, there is a need to better understand the factors at play.

There is a range of factors that may increase the risk of Ross River virus, they include suitable wetlands, wildlife reservoirs of the pathogen and mosquitoes. Understanding the mosquitoes associated with urban estuarine and freshwater wetlands is critical.

Investigating the role of surrounding landuse in determining the mosquito communities of urban mangroves, we found that industrial and residential areas tended to increase abundance of mosquitoes, perhaps due to direct or indirect impacts on the health of those mangroves. We’ve found previously that mosquitoes problems are often associated with estuarine wetlands suffering poor health, perhaps this is determining the increased mosquito risk we identified? You can read more in our publication here.

Expanding the investigation to look at urban freshwater wetlands, it was found that there was a high degree of variability in local mosquito populations and that each wetland needed to be assessed with consideration to be given to site-specific characteristics. You can read more about our work investigating mosquito assemblages associated with urban water bodies in our publication here.

More research is underway in this field and my PhD student, Jayne Hanford, has already started collecting some fascinating data on wetland biodiversity and local mosquito populations.

While the focus of our studies is often prompted by concern about Ross River virus, interestingly, in recent years we’ve found considerable activity of Stratford virus. This is not currently considered a major human health concern but given how widespread it is, it raises concerns about the suitability of local wildlife, even in Western Sydney, to represent important reservoirs of mosquito-borne pathogens. You can read more about Stratford virus in our publication here.

The final piece of the puzzle is to understand the ecological role of mosquitoes. Where their potential health threats are deemed significant, how could management of mosquito populations have unintended consequences for other wildlife. What about the animals that eat mosquitoes? A number of years ago we did some research to determine the importance of mosquitoes in the diet of coastal bats. While there was no indication that mosquitoes are a critical component of their diet, they are still being snacked on and mosquito control programs need to consider any local ecological impacts.

Now, how am I going to squeeze all this into 15 minutes….

The presentation abstract is below:

What drives mosquito-borne disease risk in urban wetlands?

Webb, C. (1, 2), J. Hanford (3), S. Claflin (4), W. Crocker (5), K. Maute (5), K. French (5), L. Gonsalves (6) & D. Hochuli (3)

(1) Department of Medical Entomology, NSW Health Pathology, Westmead Hospital, NSW 2145; (2) Marie Bashir Institute of Infectious Diseases and Biosecurity, University of Sydney, Camperdown, NSW 2006; (3) School of Life and Environmental Sciences, Faculty of Science, The University of Sydney, Camperdown, NSW, 2006; (4) Menzies Institute for Medical Research, University of Tasmania, Hobart, TAS, 7000; (5) Centre for Sustainable Ecosystem Solutions, Biological Sciences, Faculty of Science, Medicine & Health, University of Wollongong NSW, 2522; (6) School of Arts and Sciences, Australian Catholic University, North Sydney, NSW, 2060.

Managing pest and public health risks associated with constructed and rehabilitated urban wetlands is of increasing concern for local authorities. While strategic conservation of wetlands and wildlife is required to mitigate the impacts of urbanisation and climate change, concomitant increases in mosquitoes and mosquito-borne disease outbreak risk must be addressed. However, with gaps in our understanding of the ecological role of mosquitoes, could control strategies have unintended adverse impacts on vertebrate and invertebrate communities? A series of studies were undertaken in urban wetlands of greater Sydney to investigate the role of land use, wetland type and wetland aquatic biodiversity in driving the abundance and diversity of mosquito populations. A diverse range of mosquitoes, including key pest an vector species, were found in urban environments and mosquito-borne pathogens were detected in local populations, implicating local wildlife (e.g. water birds and macropods) as potential public health risk factors. Estuarine wetlands are locally important with the percentage of residential land and bushland surrounding wetlands having a negative effect on mosquito abundance and species richness while the amount of industrial land had a significant positive effect on species richness. Mosquito control in these habitats is required but insectivorous bats were identified as mosquito predators and the indirect implications of mosquito control should be considered. The aquatic biodiversity of urban freshwater wetlands influenced the species richness of local mosquito populations indicating vegetation plays an important role in determining local pest species. However, the matrix of wetland types also influences the abundance of mosquitoes in the local area. These results demonstrate the need for site-specific investigations of mosquito communities to assist local authorities develop policies for urban development and wetland rehabilitation that balance the need for conservation with reduced public health risks.

To keep up to date on what’s happening at the conference, check out the program online or follow the conversation on Twitter.

 

Could a podcast stop mosquito bites?

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This week I’m attending OzPod 2016: the Australian Podcast Conference, a workshop at the ABC, Ultimo. Celebrating International Podcast Day, the workshop brings together podcasters for “an event for the expanding podcast industry to escape the studio or office and meet with peers to share experiences, information, insights and ideas around audience acquisition and retention, new technologies, the rise of the podcast in traditional media, monetizing and of course the fine art of storytelling.”

 So, why am I going? I don’t even have a podcast!

I may not have a podcast now but I hope to start playing around with the platform soon as a complement to my other efforts to spread the word on science communication and public health awareness.

I’ve been thinking about kicking off a podcast for a while but have been a little reluctant due to time commitments. More importantly, I’ve also wanted to have a clear idea of what exactly I want to do.

In a previous life, I co-hosted a radio show on FBI Radio (during their test broadcast days) with my wife called “Good Morning Gidget”. It was a Saturday morning show of surf music and interviews with professionals involved in a wide range of coastal-based activities, from marine biologists to surf shop owners. Despite the early start on a Saturday morning, it was a load of fun. I’d also worked behind the scenes producing a couple of music shows. If I had more time, I really would have liked to pursue more work with community radio.

Perhaps podcasting will be the backup plan.

flashforward_swatting

It’s great to listen back to packaged interviews with radio, like the Health Report (I’m talking zika virus) but I was also lucky enough to have a chance to contribute to a few podcasts this year. I spoke with Science On Top about the outbreak of Zika virus and the implications it has for Australia, Flash Forward on what will happen if we eradicate mosquitoes from the planet and ArthroPod on what its like to study mosquitoes for a living!

All these were a lot of fun and were really motivating for me to want to get started with podcasting myself.

I feel like my experience with sound recording and ongoing engagement with media provides a solid background in most of the technical skills I need to get started. I’m hoping I’ll leave the OzPod 2016 conference with a few more tips on story telling and structuring a podcast too.

What I’ve been struggling with is format. I like the conversational nature of most podcasts but as I’ll probably be doing everything myself, perhaps a more structured and edited podcast is the go?

There are very few podcasts I listen to that are built around a one-person show. I’m not sure I could pull it off. Does anyone really want to listen to me ramble on for 20 mins about mosquitoes? 40minutes?

Sometime over the coming summer I hope to launch a short series of podcasts covering some of the basics of mosquito biology and how that relates to the ways we protect ourselves and our families from mosquito bites and mosquito-borne disease. I want to share my fascination with mosquitoes and explore some of the gaps in our understanding of mosquitoes, particularly their role in our local environment. 

Hopefully I can recruit some of my colleagues from around Australia for a chat too so we can share a little about the science behind our public health messages and what life is like to be chasing mosquitoes around swamps all summer

Sound like a good idea? Join the conversation on Twitter and let me know what you think, would you listen to a podcast about Australian mosquitoes?

 

 

 

 

 

 

Taking Australian wetland research to China

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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!

 

 

 

Around the world in a thousand fleas

fleas

The International Congress for Tropical Medicine and Malaria (ICTMM) kicks off in Brisbane, QLD, Australia this week running from 18 through 22 September. This is a big conference and wonderful for local researchers to be showcased to an audience of international scientists from our own backyard in QLD.

I couldn’t make this meeting unfortunately but luckily my wonderful PhD student Andrea Lawrence will be presenting some of our flea research as part of the Australian Society of Parasitology conference that is incorporated into ICTMM this time around.

Andrea has been doing some excellent research during her candidature and you can read some of it here [Evaluation of the bacterial microbiome of two flea species using different DNA isolation techniques provides insights into flea host ecology] and here [Integrated morphological and molecular identification of cat fleas (Ctenocephalides felis) and dog fleas (Ctenocephalides canis) vectoring Rickettsia felis in central Europe].

This week she will be sharing her research into the genetics of global cat flea populations. You can catch Andrea on Tuesday 20 September in the Zoonoses session in M4, 13:00-15:00.

Our abstract is below:

One thousand fleas from fifty countries: global genetic structure and morphometrics of the common cat flea (genus Ctenocephalides) reveals phylogeographic patterns and resolves the generic complex.

Andrea Lawrence, Cameron E. Webb and Jan Šlapeta

School of Life and Environmental Sciences (SoLES), Faculty of Veterinary Science, The University of Sydney, Australia and Department of Medical Entomology, The University of Sydney and Pathology West, ICPMR, Westmead, Australia

The common cat flea and its relatives (genus Ctenocephalides) are considered the most successful ectoparasites on earth. The widespread parasitisation of these insects on mammals closely associated with humans (e.g. dogs and cats) represents significant potential for vector borne disease transmission. Fleas of the genus Ctenocephalides represent a unique model to study the effects of modern human migration and geographic and climatic barriers on parasite diversity and diversification. We have amassed a world-wide collection of Ctenocephalides over a period of 7 years, and analysed over 1000 flea samples from ca. 50 countries representing all continents bar Antarctica. Novel integration of morphology, morphometrics and molecular identification and phylogenetics using a combination of four mitochondrial and nuclear DNA markers, reveals phylogeographic patterns and evolutionary relationships of global cat flea populations. These techniques provide resolution of the long disputed Ctenocephalides generic complex, which has not yet been definitively resolved despite its significance in veterinary and public health. Understanding of contemporary population structure inferred from global phylogeographic analysis has implications for parasite and flea-borne disease management. It is hoped that this work will form the authoritative estimation of the origin of the genus Ctenocephalides and the subsequent species evolution and migratory radiation.

Keep an eye on the official conference hashtag [#ICTMM2016] and why not follow Andrea on Twitter for more!

The lead image on this article is modified from Andrea’s paper, “High phylogenetic diversity of the cat flea (Ctenocephalides felis) at two mitochondrial DNA markers