Social media and blood suckers showcased at the International Congress of Entomology


Digital technology is changing a lot about how we undertake entomological research and communicate the results of that research to the community and policy makers.

This week in Orlando, Florida, is the International Congress of Entomology (ICE). A huge gathering of entomologists from around the world. While it was a great pleasure to be invited to participate, I couldn’t get over there this time.

I will, however, have a chance to present my work in the Symposium “Entomology in the Digital Age”  Friday, September 30, 2016 (01:30 PM – 04:45 PM), Convention Centre Room W222 A.

In the presentation I’ll share some of the reasoning behind my use of social media to engage the community with both entomological research and public health communication. Most importantly, it will focus on some of the metrics I’ve recorded alongside my use of social media, maintaining a blog of research and writing for outlets such as The Conversation.

I’ve written about my use of social media and how it can help extend the reach of public health messages and presented on the topic alongside a range of great speakers at the 2014 Entomological Society of America meeting in Portland.

This time around, technology is playing an even more direct role in my presentation! I’ve pre-recorded my presentation and it will be shown to the audience on the day among other presentations. I’ll also be checking into the session to answer questions. Despite the fact I’ll need to be up around 1:30am due to time differences, it should be fun.

See the abstract below…

Taking entomological research from the swamps to the suburbs with social media

Cameron E Webb

Connecting scientists and the community is critical. This is particularly the case for medical entomologists working in the field of mosquito-borne disease where the translation of entomological research into improved public health outcomes is a priority. While traditional media has been the mainstay of public health communications by local authorities, social media provides new avenues for disseminating information and engaging with the wider community. This presentation will share some insights into how the use of social media has connected new and old communications strategies to not only extend the reach of public health messages but also provide an opportunity to promote entomological research and wetland conservation. A range of social media platforms, including Twitter, Instagram, and WordPress, were employed to disseminate public health messages and engage the community and traditional media outlets. Engagement with the accounts of traditional media (e.g. radio, print, television, online) was found to be the main route to increased exposure and, subsequently, to increased access of public health information online. With the increasing accessibility of the community to online resources via smartphones, researchers and public health advocates must develop strategies to effectively use social media. Many people now turn to social media as a source of news and information and those in the field of public health, as well as entomological research more generally, must take advantage of these new opportunities. doi: 10.1603/ICE.2016.94611

If you’re at ICE, you can also catch up with my PhD student David Lilly who’ll be presenting our research into the development of insecticide resistance in bed bugs as part of the symposium “New Insights into Biology, Resistance Mechanisms, and the Management of the Modern Bed Bug” Friday, September 30, 2016, 01:30 PM – 04:45 PM, Convention Center, West Hall F4 (WF4).

Novel insecticide resistant mechanisms in the common bed bug, Cimex lectularius

David Lilly, Cameron E Webb and Stephen Doggett

Introduction: Research on field strains of Cimex lectularius from Australia has identified widespread resistance to pyrethroid insecticides, but variability in the magnitude expressed. To determine if differences in resistance mechanisms exist, collected strains were examined for the presence of metabolic detoxification and/or cuticle thickening. Methods: The presence and relative contribution of detoxifying esterases or cytochrome P450 monooxygenases were assessed. Bed bugs collected from Parramatta (NSW), Melbourne (VIC) – 2 strains, ‘No.2’ and ‘No.4’, and Alice Springs (NT) were exposed in topical bioassays employing deltamethrin and two pyrethroid synergists: piperonyl butoxide (PBO) and EN16/5-1. PBO inhibits both monooxygenases and esterases, whereas EN16/5-1 will inhibit esterases only. Thus in a comparative bioassay, the results can infer the dominant enzyme system. The Parramatta strain was then selected to study the potential presence of cuticle thickening. Nine-day-old male bed bugs were exposed to filter papers treated with the highest label rate of Demand Insecticide®(200mL/10L of 25g/L lambda-cyhalothrin) and were grouped according to time-to-knockdown (< 2 hours, ≥ 4 hours, and survivors at 24 hours). Measurements of mean cuticle thickness at the transverse midpoint of the second leg tarsus were taken under electron microscope. Results/Conclusion: All strains possessed resistance that was inhibited by the synergists, with the Parramatta and Melbourne No.2 indicating esterase-dominance, and Alice Springs and Melbourne No.4 indicating cytochrome P450 monooxygenase-dominance. Cuticular measurements demonstrated that bed bugs surviving deltamethrin exposure had significantly thicker cuticles, denoting a novel form of resistance in these insects. doi: 10.1603/ICE.2016.92553


You can also see Stephen Doggett (co-author and photographer of A Guide to Mosquitoes of Australia) speaking on photographing mosquitoes to in the symposium “Insect Photography Symposium: Bringing the Small to the World.

You can join the conversation on Twitter and keep an eye on all the fun in Orlando by keeping an eye on the tweet stream!


Putting a value on science communication

For many scientists, communicating the ideas that underpin their areas of expertise to the public and policy makers is critical. Sharing the findings of research could make a difference to people’s lives, even if it is just to increase their appreciate of science and the world around them. But how do we value the communication of science by scientists?

Scientists often bemoan the lack of acknowledgment of their scientific communications and community engagement efforts. There is little doubt that these “outreach” activities receive far less “academic credit” than publication in high impact journals.

Writing for “popular science” outlets is often perceived to be a career negative. While some argue there needs to be capacity for the community engagement efforts of scientists to be acknowledged in the assessment of academic accomplishment, others argue against it. Regardless of your motivations, if you’re going to engage in science communication, it is best to make the most of your activities but even when your research goes vial, how can you put a value on this?

How can you value your science communications in a way that may be recognised for employment, promotion, grant applications etc?

repellentbandOne of my recent articles for The Conversation, why mosquitoes seem to bite some people more, went a little bit viral. Almost 1.3 million people clicked on that article. Would I swap it for an article in Nature (or any other scholarly publication with a high impact factor) that only 20 people read? Probably as it would make a far more valuable contribution to my career…but would it have the same potential to change people’s awareness and behaviour in avoiding mosquito bites? Probably not.

I’ve written before about the importance of social media in getting the public health messages informed by my research out to the public. A blog post I wrote about the shortcomings of mosquito repellent wrist bands in protecting people against mosquito bites is the most read post on my blog. Since first published, the article “Do mosquito repellent wrist bands work?” has been read by around 47,000 people. The original paper, published in a journal without an impact factor, may have been read by only dozens of people if I hadn’t written about it on my blog.


I’m increasingly asked to provide evidence of “engagement” or “translation” activities associated with my research. This is particularly the case for my activities with Centre for infectious Disease and Microbiology Public Health where translating research for improved public health outcomes is a key objective. Those outcomes have generally been focused on providing informed guidance to local authorities on infectious disease surveillance, diagnosis and treatment.

What about community engagement?

I wanted to share how I’ve been trying to value my science communication activities in recent years. My general approach to this is to document as much detail as possible about individual activities, try to quantify the reach of activities (as much as possible) and to try to use my experience with these activities into what could be best described as my “core” activities.

In the same way you may incorporate a new laboratory technique or statistical analysis into your research, why not incorporate your science communication activities similarly?


Every summer I find myself standing in the mangroves talking to a camera (while being bitten by mosquitoes)

Media activities

In the summer past, I’ve been interviewed about 50 times on research findings, disease outbreaks and topical issues associated with mosquitoes and mosquito-borne disease. This level of activity clearly holds the potential to engage the wider community with important public health messages as well as (hopefully) improve their understanding of local scientists and their research.

While keeping a track of the interviews and their details (date, topic, journalist, outlet etc) is handy, it is also possible to go beyond that to record audience reach and assign a relative value. This is where you’ll need the help of your institute’s media and communications unit. They should be able to obtain reports from media monitoring organisations that keep track of details (interview summary points and duration, audience size, estimated value) associated with media activities.

For example, on 16 January 2015 I did a live cross to Channel 7’s Sunrise program. The interview ran for just over 3 minutes, issues about mosquito-borne disease risk and personal protection measures were covered, it had an estimated audience of over 500,000 and was valued at around $200,000.

Over the course of a year (or perhaps a research project), it is possible to assign both a financial and engagement value? For me, the media activities over the 2014-2015 summer had an estimate audience of around 8 million and value of over $600,000. This extra level of detail adds so much extra weight to the value of science communications activities.


Mosquito Bites is the bulletin of the Mosquito Control Association of Australia. Distributed to members throughout Australia and many other countries, it provides information on the operational aspects of mosquito and mosquito-borne disease management.

Popular science writing

I regularly contribute articles to non-scholarly publications, these include newsletters, bulletins and magazines produced by local community groups, industry bodies and scientific associations. As well as recording the specific details about each article, it is also possible to record circulation as a measure of engagement.

If you need to add a financial value to these articles, why not consider what the current rates are for freelance journalists? They seem to be around $0.40-1.00 per word, that makes any (non-scholarly journal) writing associated with research projects as an “in kind” contribution valued at around $500-600? Planning on writing an article associated with an upcoming research project, why not include this extra value as an “in kind” contribution?

I regularly write for The Conversation. The website provides excellent data on the readership of individual articles (including with respect to other contributors from your institution) in addition to republication and social network sharing. Most of my articles receive around 6,000-8,000 reads but many have also reached around 20,000. Again, this is typically substantially greater exposure than received by my articles in scholarly journals. Recording this additional information would help make a handy argument that non-academic writing holds value, especially when arguing about research translation.

Output from @mozziebites Twitter Analytics for February 2015

Output from @mozziebites Twitter Analytics for February 2015 showing data on impressions and engagement with my Tweets during the month.

Social media activity

Got a Twitter account or Facebook page? It is obviously great to keep track of your follower numbers, retweets, likes and shares of tweets and posts. It is a way to demonstrate engagement with the community. I started tracking my activity on Twitter early on. I was partly interested in whether people would engage with tweets about mozzies but I also wanted to demonstrate to my “bosses” that using social media for “work purposes” had some benefits in line with the public health objectives of my research activities. There was also a very nice paper published in 2012 that provided a framework for assessing the engagement of health authorities with social media and I wanted to gather similar data.

For Twitter users, you can access data on your own account via Twitter Analytics. It provides plenty of useful information, especially engagements (i.e. total number of times a user interacted with a Tweet, including retweets, replies, follows, favorites, links, cards, hashtags, embedded media, username, profile photo, or Tweet expansion), impressions (i.e. times a user is served a Tweet in timeline or search results) and link clicks (i.e. clicks on a URL in the Tweet). This kind of data can help demonstrate the extent to which the online community is interacting with your own social media activity.

It will also help if you engage with your institution on social media. Help promote their activities and those of your colleagues and collaborators. In turn they’ll help raise your profile too.


Speaking at public events provides opportunities to meet a wide cross section of the community….even celebrities such as Jimmy Giggle at the ABC community event at Parramatta Park, April 2014.

Community presentations

Every year i speak at a range of community events. In the past year or so I’ve spoken at such diverse events as Sydney Olympic Park Authority’s Life in the Park, Australian Skeptics in the Pub, Cumberland Birds Observer’s Cub meeting, Oatley Flora and Fauna Conservation Society meeting and Pint of Science. This provides an opportunity to speak to a wide cross section of the community but is also an opportunity to document experience in communicating to different audiences.

As well as keeping track of these speaking engagements (date, title, location, hosting organisation), I also try to record the number of attendees and most of the time I make a note of questions asked. This, again, is a way to document engagement/translation of research. It can also form a foundation for how you may shape research, it has particularly been the case for me reviewing the way we share public health information relating to the promotion of insect repellent use.

Communications and publications

Finally, think about ways you can parlay your experience with science communication into output that’s recognised by your organisation or institute. Why not write a perspectives piece, commentary or letter to the editor? I’m regularly seeing articles popping up in peer reviewed journals explaining the benefits of using social media, why not target a journal within your field that may not have covered the topic. You only need to see the metrics on this paper, ‘An Introduction to Social Media for Scientists‘, to realise that there is plenty of interest and having an extra journal article under your belt won’t hurt either.

Similarly, if you’re being asked to speak at conferences and workshops on your use of social media and/or science communication strategies, make sure you’re recording all those details too.

To conclude, there may not (yet) be a magic number to assign to your science communications activity in the same way impact factors and altmetrics help measure the success of traditional academic output. However, that doesn’t mean you cannot record a bunch of “metrics” associated with science communications, both online and off, that will hopefully better place you for that next job offer or promotion.

What do you think? How do you document your scientific communications activities? Join the conversation on Twitter.

Why would a Californian drought trigger an outbreak of mosquito-borne disease?

CalifornianBushfireSunset_DawnEllnerMosquitoes need water almost as much as they need blood so why is it a drought could cause an outbreak of mosquito-borne disease? Why does the drought in California mean less water but more mosquito-borne disease?

More than just water

All mosquitoes need water. It could be a teaspoon of water in a pot plant base or an expanse of wetlands inundated by tides. Following flooding, health authorities are typically quick to issue public health warnings about increased risk of mosquito-borne disease. However, more mosquitoes doesn’t always mean more mosquito-borne disease.

Mosquitoes need blood. As well as biting people, they also bite animals. Outbreaks of mosquito-borne disease typically requires the presence of wildlife, animals that act as reservoirs for the disease-causing viruses.


Drought is hitting California hard (Source EPA via Huffington Post)

Mosquitoes, drought and West Nile virus

West Nile virus is a mosquito-borne pathogen generally spread between birds and people by mosquitoes. Culex mosquitoes they appear to play the most important role in West Nile virus transmission in urban environments, particularly Culex pipiens.

These mosquitoes are generally not breeding in wetlands. They’re found in artificial structures ranging from backyard containers and neglected swimming pools to stormwater pipes and drains. These mosquitoes have moved out of the swamps and into the suburbs! They’ve also moved into the constructed wetlands popping up throughout the suburbs too.

Rather than water birds associated with wetland environments, the birds playing a key role in West Nile virus transmission are small songbirds common in urban areas. These birds roost in large numbers and are the target the the Culex mosquitoes that preferentially feed on birds. It is important to keep in mind that there is still a lot of learn about how the roosting behaviour of birds influences their exposure to West Nile virus.

During “dry” conditions, bird populations are concentrated in urban areas (where humans provide water and food) and mosquito populations associated with urban water-holding structures increase. During “wet” summers, bird populations may be more widely dispersed through the environment with many birds roosting and foraging well away from residential areas and reducing the contact between birds, mosquitoes and people. When the “dry” summers arrive, birds move back close to the people. People who provide water.


The Culex pipiens group of mosquitoes play an important role in the transmission of West Nile virus and are closely associated with urban environments. They like biting birds. (Photo: Stephen Doggett, NSW Health Pathology)

In the absence of rain, water stagnates in stormwater pipes and drains providing favourable conditions for mosquitoes. During “wet” summers, the mosquitoes are flushed out by increased water flows and, even if they don’t, permanent habitats are more likely to support populations of mosquito predators such as fish.

During “dry” summers, people also start storing water around the home. Once water restrictions kick in, the desire to keep the garden looking healthy can potentially pose an indirect health risk to the homeowner as they hoard water around the home that provides habitat for mosquitoes.

In short, dry conditions help concentrate mosquitoes and birds in close proximity to people and increase the risk of mosquito-borne disease outbreaks.


Mosquito control in Texas in response to an outbreak of West Nile virus raised much concern within the community. It can sometimes be difficult to balance the need for mosquito control with community engagement to allay fears of insecticide -based human health risks (Source: CDC)

An outbreak in Texas in 2012

West Nile virus was first introduced into North America in 1999. Despite rapidly spreading across the continent in the subsequent years, the numbers of outbreaks steadily declined and, to some extent, it fell of the radar as a serious public health concern. There was a resurgence of the disease in 2012 with an outbreak primarily focused in Texas.

There was a substantial increase in the number of cases compared to previous years with an unusually warm spring thought to have played an important role in driving the outbreak. Health authorities were warned that outbreaks of this nature may continue.

USDroughtMonitors_7April2015West Nile virus and the Californian drought

For the past couple of years, California has been hit with one of its worst droughts in decades. It is having widespread impacts and may also be increasing mosquito-borne disease. Californian authorities have been battling potential public health risks associated with mosquitoes on many fronts. There were record numbers of deaths due to West Nile virus disease in 2014 and exotic mosquitoes were detected. This included an Australian mosquito that was found in Los Angeles.

It is relatively early in California’s mosquito season but West Nile virus has already been detected. Health authorities are warning that another bad year for West Nile virus activity could be ahead despite the ongoing drought. There is already a suggestion that the severity of the current drought may be exacerbated by climate change and that climate change may be playing a role in future West Nile virus risk internationally.

There is little doubt that prolonged drought will impact Californian residents in many ways and an increased risk of mosquito-borne disease is just one of them. Fortunately, mosquito and vector control agencies in California work closely with local health authorities to monitoring mosquito and pathogen activity to provide warnings of increased risk. However, there is responsibility for everyone to ensure that the ways in which water is conserved around the home doesn’t increase the risks associated with mosquitoes.


If you’re worried about keeping your pot plants well watered but don’t want to provide a home for mosquitoes, fill the saucer with sand. It will keep the moisture in place but there is no “free water” for mozzies to use!

If you’re not able to “dump and drain” water holding containers, make sure that they’re covered to stop mosquitoes getting in or out. If you’ve got a swimming pool that’s neglected, start chlorinating it or release fish to eat through any mosquitoes. There are also a few mosquito control products that could be used, the most appropriate would probably be the insect growth regulator methoprene, it will stop mosquitoes emerging from the water holding container.

Why not share your tips on saving water around the home while not increasing opportunities for mosquitoes on Twitter?

The photo at the top of this post is taken by Dawn Ellner (see original photo here)

Why are mosquitoes so bad this summer?

Swarms of mosquitoes are descending on Sydney. It’s been one of the worst starts to summer for pesky mozzies and it’s only going to get worse.

Mosquitoes need water and there’s been plenty of it. Water filling up our wetlands or backyard buckets provides habitat for mosquitoes. Warm humid weather also helps keep mosquitoes alive longer. That’s right, there are more mosquitoes and they’re living longer!


The saltmarsh mosqutio, Aedes vigilax, is closely associated with tidally influenced estuarine wetlands along most of Australia’s coast (image: Stephen Doggett)

Predicting boosts in mosquito numbers isn’t always easy. The reason is that mosquitoes respond to the pattern of rainfall, not just the quantity.

Rain, Rain, Rain

We’ve had over 160mm of rain in Sydney in just the first 10 days of December. The long-term average is 70mm. It is when this rain is falling that makes the difference. If we’d had it all over a couple of days, there would have been one hatch of mosquitoes. Just one generation of adults buzzing about. Problem is we’ve had steady rain. It’s been spread out and so have been the hatches of mosquitoes. It keeps the wetlands flooded too so any wrigglers that have hatched from eggs won’t be stranded in a drying puddle.


Total daily rainfall recorded at Sydney Olympic Park (Data source: Bureau of Meteorology)

The rain is one thing but tides play a role too. While backyard mozzies rely on rainfall, our biggest nuisance biting pest, the saltmarsh mosquito (Aedes vigilax), relies on a combination of rainfall and tidal flooding of local wetlands. Funnily enough, they generally love a hot dry summer.

Swimming with the tide

In a cruel twist of fate, we’ve had tidal flooding of local wetlands at the same time as all the rain. The tides were nothing compared to the “king tides” we experienced last summer but, in combination with the rain, it resulted in complete flooding of our local estuarine wetlands. Maximum occupancy for mosquitoes.

Current monitoring along the east coast, particularly in areas close to estuarine wetlands, are recording above average numbers of mosquitoes. The collections are currently dominated by saltmarsh mosquitoes but there are plenty of “backyard” mozzies too. The current generation of mosquitoes was triggered by environmental factors in mid to late November.

Problem is, we’re going to see more as the next generation is currently wriggling about in our wetlands and backyard habitats. They’ll be emerging over the next few days….

While the current rain and tides are playing their part, something happened way back in October that set the wheels in motion for the marauding mozzies.

Springing into Summer

The hottest spring on record set the scene. Then, around the middle of October, there was about 100mm of rain that followed a few days after a series of higher than expected tides. Historically, regardless of rain, tides or temperature, there is rarely a substantial increase in mosquitoes. This year was different. it was a perfect storm of climatic conditions that “woke up” local mosquito populations a month or so early.

The early start to the season took everyone by surprise. The state-wide mosquito monitoring program generally only kicks off in coastal areas in December and there has never been any mosquito control in local wetlands in October. While I was filming a piece for Chanel 9 News along the banks of the Parramatta River, we were eaten alive by mozzies. I’d never seen so many that early in the season.

henandchickenbay_stormfrontMy experience in the past is that once mosquito populations gain some momentum, only an extended hot and dry period will slow them down. Each mosquito can lay up to (or beyond) 100 eggs. The more mosquitoes, the more eggs. The more eggs, the more mosquitoes. The cycle continues. The short-term forecasts are for  warm and humid weather along with continuing storms. Unfortunately, there may not be a break from mosquitoes for a while yet.

What can you do the beat the bite?

Here are five tips that will help beat the mozzie bites this summer.

1. Tip out, drain or cover any water-holding containers in the backyard. They may be buckets, discarded tyres or a taupaulin covering an old trailer or boat. Anything that collects water can be used by mosquitoes. Make sure your rainwater tank is correctly screened and your roof gutters are clean and free-flowing.

2. Screen your windows. This may not help when you’re outside but it will at least stop them coming inside. If you live near wetlands, give some serious thought to creating a screened outdoor area. There are lots of flexible screening options available. This is common place in some parts of North America and Europe, I don’t know why we don’t do it more of ten here in Australia.

3. Cover up or wear repellent. If you’re outdoors, particularly at dawn or dusk, cover up with long sleeved shirts and long pants. Pale colours tend not to attract so many mosquitoes. Apply repellent to any exposed areas of skin. There are lots of tips on using repellents here and here and here.

4. Sprays and coils and sticks and zappers. There are plenty of products available that contain insecticides. Aerosol “fly sprays” will help get rid of a mozzie buzzing about indoors but the better option are the “plugin” zappers that heat a small reservoir of insecticide. These are very effective and safer to use indoors than burning a mosquito coil. Mozzie coils and sticks should only be burnt outdoors or in sheltered areas. Pick a product that contains an insecticide. The botanical (e.g. citronella) based products will hep reduce the total number of bites but not prevent them all.

5. Listen out for warnings. Stay tuned to local radio, or keep your eye on the website of local health authorities. Mosquito bites can be pretty annoying but there is also concern regarding mosquito-borne diseases, particularly those such as Ross River virus. There is a number of state-based surveillance programs in place and warnings are often issued when elevated levels of pathogen activity is detected in local mosquitoes or there is an increase in human disease reported.

Join the conversation on Twitter. Is this the worst summer for mosquitoes in your part of Australia?



World Health Day 2014: An Australian perspective

WHO_WHD2014_SmallBiteBigThreatMonday 7 April is World Health Day. Every year, to mark the anniversary of the founding of WHO in 1948, the World Health Organization draws attention to a public health problem of global proportions and what needs to be done to address it. The theme is vector-borne disease with the key message that a small bite can be a big threat.

There are some wonderful resources available at the WHO website including information on the key vector-borne diseases internationally and what can be done to combat the vectors and reduce the burden of disease. One of the key messages is that while more than half of the world’s population is at risk of vector-borne diseases and increased travel, trade and migration make even more people vulnerable, these diseases are preventable.

What about Australia?

Australia may be fortunate in that we’re free of some of the nastiest pathogens spread by mosquitoes, we still have our own home grown viruses. Exotic pathogens are also increasingly knocking at our door. While countries in our region battle with outbreaks of mosquito-borne dengue, chikungunya and zika viruses, and Australian travellers are increasingly returning home either infected with these pathogens, or potentially carrying exotic mosquitoes.

In recent years we’ve had a case of “airport dengue” in Darwin, the first case of locally acquired dengue in Western Australia for 70 years, the first imported human case of zika virus, detection of yellow fever mosquitoes in Melbourne and activity of Ross River virus making its way into residential areas of Sydney.

Notwithstanding our “home grown” pathogens, that circulate amongst endemic mosquitoes and local wildlife,  exotic threats continue to threatened our shores.

It wasn’t until the 1980s that Australia was declared free of malaria. Historically, there were cases throughout the country but now the risks are considered minimal. It is, however, important to note that there are small risks of local outbreaks as highlighted by a small cluster of cases in Far North QLD in 2002. While there remains a risk to travellers, the availability of effective prophylaxis reduces those risks. However, the number and type of imported cases of malaria into Australia in the future may be determined by a range of factors including the resettlement of people from endemic countries, as well as military and civilian activities.

Aedes aegypti (Photo: Stephen Doggett)

The Yellow Fever mosquito, Aedes aegypti (Photo: Stephen Doggett)

Yellow Fever hasn’t impacted Australia to the extent of many other regions of the world. While we’ve seen increasing numbers of imported dengue and chikungunya, there have been very few imported cases of Yellow Fever reported with only two since 1991. However, recent studies have suggested that Australian mosquitoes readily become infected with and can transmit representative African and South American strains of Yellow Fever virus. The question remains as to the potential for local outbreaks to be triggered by returning travellers but perhaps we are fortunate that the availability of an effective vaccine and quarantine reviews of travellers returning from yellow fever endemic regions (Australians visiting yellow fever-endemic countries may be required to show proof of vaccination with a WHO International Certificate of Vaccination ) assists in reducing outbreak risk. Be careful if you’re heading to the World Cup in Brazil!

WHO_WHD2014_SmallBiteBigThreat_boyJapanese encephalitis virus has been knocking on our door for a while. While it is not considered a high risk for short-term travellers to endemic regions, northern Australia may be impacted. Most notable was an outbreak in the Torres Strait in 1995. While the availability of a vaccine can greatly reduce the risks, given the similarities between the mosquito populations of Torres Strait and northern Australia, concerns were raised as to the risks that may exist for transmission to occur more widely on mainland Australia. Studies assessing the risk to mainland Australia revealed some fascinating factors that may drive public health risks, from high altitude wind dispersed mosquitoes to genetic differences between local mosquito species. Despite the virus being isolated from mosquitoes collected on mainland Australia and debate continues as to any likely activity in northern mainland Australia there generally appears to be very low risk that transmission will occur more widely. Perhaps the greatest risk will be if human population grows in northern Australia?

Although imported cases in travellers, as well as refugees, are occasionally reported, until recently, Australia was considered free of Leishmaniasis. However, the discovery of parasites in red kangaroos (as well as a black wallaroo and agile wallabies) and subsequent incrimination of biting midges has changed the way local health authorities look at Australia’s susceptibility to these parasites. One of the most interesting aspects of recent research is the identification of biting midges as playing a potential role in local transmission. Biting midges (Diptera: Ceratopogonidae) are commonly known as sand flies in Australia but true sand flies (Diptera: Phlebotominae) are considered the primary vectors of Leishmania parasites. The absence of human biting species of Australian sand flies has often been cited as a reason the disease poses little risk here. More research is needed to better understand the local risks factors. However, like many of the pathogens discussed here, increased global travel from endemic regions is likely to be the biggest future risk factor.

It is probably dengue that poses the biggest threat to Australia. Historically, dengue posed a risk to communities along the east and west coasts of the country but since the 1950s, activity has been limited to Far North QLD. The current risk areas of dengue are determined by the presence of the only mosquito species in Australia currently capable of transmitting the viruses, Aedes aegypti. Local outbreaks are triggered by travellers introducing the pathogen to local mosquito populations and the number of cases reported can range from less than 100 to around 10000 each year. The future risks posed to Australia by dengue will be driven by the introduction of new vector species, such as the Asian Tiger Mosquito, Aedes albopictus, as well as increasing activity of dengue viruses in our region.

Think global and think local

It is easy for Australians and Australian authorities to become complacent of these vector-borne diseases. When we read news of outbreaks on a massive scale overseas, it is difficult to connect a threat to our local suburb. However, the critical factor across many of these pathogens is that increasing globalisation and fast international travel can expose Australia to both the pathogens and their vectors. We need to appreciate the risks and anticipate the threats. Ensuring that we maintain the capacity for quarantine surveillance and strategic responses to the detection of pathogens and vectors will be critical.

This wonderful info-graphic below from WHO on the simple steps you can take to reduce the risks of mosquito-borne disease to you and your family apply just as much to Australia as any other country on earth. It only takes one bite and over half the world’s population at risk of these pathogens. With cases of mosquito-borne Ross River virus reported from every state and territory in Australia, that includes us!

WHO_VectorborneDiseaseguidelinesFor more information, visit the official World Health Day site.





Taking the taste test with MyScience

FoodcolourHow can coloured plates and sour lollies teach primary school students about science?

For the second year in a row I volunteered in the MyScience program. The program began  in 2006 as “a collaboration between the University of Sydney, the Australian Catholic University, IBM and the NSW Department of Education and Training (Western Sydney Region) to fulfill their common goals of improving primary science education and encouraging students to take an interest in science and technology”.

The program encourages professionals with a science and/or technology background to volunteer in a local school to help teach primary school students about the process of scientific experimentation. It is designed to help the students turn their minds to the process of developing testable questions about how the world works and to try and design experiments to investigate these questions. As does the CSIRO Scientists in Schools and Australian Academy of Science’s Science by Doing programs, MyScience aims to introduce the world of science and technology to school students and encourage them to become the next generation of researchers and innovators. If the calls for scientific research to become a national priority are answered, we’re going to need to ensure that there is a steady flow of “bright young minds” forming the next generation of scientists.

The theme for MyScience this year was food. Unsurprisingly, most the experiments revolved around lollies/candy/sweets. In particular, skittles and warheads. Don’t ask me why but the kids love warheads. If you’re not familiar with them, they’re a hard sweet ball covered in the most sour tasting substance imaginable.

I supervised four pairs of Year 4 students (aged 9-10), each had to come up with a question about food and work out an experiment to test that question.

There were two particular projects that worked out really well.

The first was looking at how plate colour influenced volunteer’s choice of food. There are specific fields of science dedicated to this kind of research. Researchers have looked at how food colour, as well as plate colour and shape, influences the perception of taste. Even the type of cutlery can make a difference! Is colour-related food choice inherited or developed through empirical learning? An experiment like this, as well as providing an opportunity to do some neat experiments, may provide an opportunity to discuss the issue of food packaging and marketing.

The students laid out three colour plates, each with a group of lollies. While I tried to encourage the students to use sliced apple as the “food”, I quickly realised it was a battle I wouldn’t win. The students then recruited their class mates to line up and take turns selecting the plate from which they would like a lolly. The number of times each coloured plate was selected was then recorded.

chartIt probably comes as no surprise that most volunteers chose lollies from the red plate. This is actually in line with some published studies. Studies have suggested that foods with green labels are perceived to be healthier but I’m not sure if that means that “unhealthy food” is more likely to be associated with red! It does seem that colour pays an important role in food choice by children.

The best thing about the experiment was that the students really were excited to see that there was a difference in the selection trends of their volunteers. As the sample size grew and the trend become more pronounced, they got even more excited. In the end, it was a nice clear cut experiment that allowed them to make a nice simple chart of results to present to their class.

lemonThe second experiment was more of a demonstration that a true experiment. The real focus of these students’ question was to determine if sour lollies were more sour than sour fruit. They asked volunteers to taste one of the sour lollies, and then a piece of lemon, and pick the most sour. The students didn’t place too much emphasis on gathering a decent sample size. They stopped at three volunteers. While they may not have been quite as enthusiastic about the first part of the experiment, I took the chance to work up a demonstration to teach them about food acid and how it relates to taste.

Warheads are dusted in malic acid (dicarboxylic acid). When you suck them, there is an intense sour taste that lasts about 30sec. How could you demonstrate that it is the acid that causes the sour taste and why does it stop?


I made up two solutions of sodium bicarbonate (roughly 1 teaspoon of bicarb mixed into 50ml of lukewarm water). If you drop a freshly opened warhead into the solution, it fizzes up and looks reasonably dramatic. Next, one of the students takes another freshly opened warhead and sucks it until the sour taste is gone. Now drop that “sucked” warhead into the second solution. No bubbles. No fizz.

While this may seem like a fairly basic demonstration, the students were generally excited and during their science fair, it was one of the most popular demonstrations of the morning. This was probably due in part to the joy of watching teachers and parents enduring the sourness of the warheads in front of the students!

Overall, the My Science program has benefits both for the students but also the volunteers. I’ve found that breaking down the process of experimentation and thinking about how to explain concepts to primary school students greatly improves the way I approach communication of “medical entomology” issues to the general public and media. If an eight year old can understand my explainations, I’m hoping everyone else can too.

Real Scientists and Canberra’s Constructed Swamps

An example of constructed wetlands near Canberra, ACT, Australia

An example of constructed wetlands near Canberra, ACT, Australia

A wonderful new resource has been created called “Real Scientists“. The idea behind this is to create a Twitter account (@realscientists) to showcase  scientists, science communicators, writers and artists to talk about their lives and their work. I’ve been invited to guest tweet between Wednesday 12 and Saturday 15 February 2013.

This guest tweeting stint coincides with a field trip to the ACT to undertake mosquito surveys in and around natural and constructed wetlands. I’ll be tweeting the ups and downs, frustrations and discoveries associated with mosquito population sampling.

There are three main reasons behind this work. Firstly, there are actually very few records of the mosquito fauna in the ACT. We have considerable data on the abundance and diversity of mosquitoes across much of NSW but there is a little black hole of data that needs to be filled around Canberra. An understanding of the abundance and diversity of mosquitoes in the region will assist local authorities manage actual or potential risks of nuisance-biting impacts and/or outbreaks of diseases caused by mosquito-borne viruses such as Ross River virus or Barmah Forest virus.

An example of constructed wetlands associated with new urban developments in Canberra

An example of constructed wetlands associated with new urban developments in Canberra

Secondly, one of my major research interests is the role of urban development on mosquito-borne disease risk. Much of my research is conducted in the coastal regions of NSW where an assessment of risks relies on balancing the impact of mosquitoes from both coastal estuarine and local freshwater wetlands. Understanding how these mosquitoes respond to the creation and/or rehabilitation of local freshwater wetlands, against the background of “estuarine” mosquito pests, can help manage public health risks.

The newly expanding residential areas of the ACT provide a unique opportunity to study the response of local mosquitoes. Generally speaking, there are few naturally occurring mosquito habitats around Canberra. However, in conjunction with new urban developments, wetlands are being constructed that have the potential to increase available mosquito habitats. Do these constructed habitats provide suitable conditions for local pest mosquitoes?

Finally, I’m interested in the dynamics between mosquitoes, the pathogens they transmit and local wildlife. Mosquitoes don’t emerge from wetlands infected with a virus, they must bite an infected animal first. Those animals are typically kangaroos and wallabies. For an elevated public health risk locally, abundant mosquitoes, wildlife and the viruses are required. For example, along the Parramatta River in Sydney, there can be very abundant mosquito populations but as there are no suitable populations of wildlife that carry Ross River virus, the health risks are low. However, drive a couple of hours south and you can find large populations of mosquitoes, abundant macropod populations and it is in these regions where mosquito-borne disease risk is greater.

The areas around Canberra provide an interesting situation in that even though mosquito populations are generally considered low, kangaroos are common and regularly move through the suburbs. What are the implications for mosquito-borne disease risk? Do “backyard” mosquitoes play a relatively more important role than “wetland” mosquitoes?

Please drop by the “Real Scientists” twitter feed to see what happens….

Does male diet influence mosquito reproduction?

My latest publication has appeared in the Journal of the American Mosquito Control Association in December 2012. This paper reports on some biological experiments conducted by my PhD student Nur Abu Kassim. She was interested in investigating the role of diet (including how much food immature stages ate and if adult mosquitoes had access to sugar) on male mosquitoes and the resulting egg development by females.

Nur conducted her experiments using Culex molestus, this species is a member of the Culex pipiens group. This group of mosquitoes is important internationally as it contains species closely associated with the transmission of disease-causing pathogens, in particular West Nile virus. Culex molestus is an interesting species in that it can develop its first batch of eggs without a blood meal. You can read about our earlier studies here and here.

The results indicated that diet of male mosquitoes, both access to food in immature stages and access to sugar as adults, influenced the number of autogenous eggs and hatching rates of those eggs.

Here is the abstract:

Culex molestus is an obligatory autogenous mosquito that is closely associated with subterranean habitats in urban areas. The objective of our study was to investigate the influence of larval and adult nutrition on the role of males in determining the expression of autogeny in Cx. molestus. Mosquitoes raised at low and high larval diets had sex ratio, wing length, mating rates, autogenous egg raft size, and hatching rates recorded. There was a higher ratio of males to females when raised at a low larval diet. Mean wing lengths of both males and females were significantly greater when raised at the high larval diet regime. Regardless of larval or adult diet, males mated with only a single female. Mosquitoes raised at the higher larval diet regimes developed significantly more autogenous eggs. However, the egg raft size was reduced when adult females were denied access to sugar. The results of this study indicate that the performance of males in the reproductive process is influenced by both larval diet and adult sugar feeding.

Full reference:

Kassim NFA, Webb CE & Russell RC. 2012. The Importance of Males: Larval Diet and Adult Sugar Feeding Influences Reproduction in Culex molestus. Journal of the American Mosquito Control Association 28(4):312-316. online


Urban development and mosquito-borne disease


In November 2012, I presented some of my work associated with Mosquito Risk Assessment and urban planning at the Australian Entomological Society and Australasian Arachnological Society – 2012 Conference, Hobart, Tasmania.

The title of my presentation was “Taking an ecological approach to wetland rehabilitation and urban development to reduce the risks of mosquito-borne disease in Australia“. The abstract is below.

Mosquito-borne disease management in coastal Australia faces many challenges. Increasing urbanisation is bringing the community closer to productive mosquito habitats but environmental management of coastal wetlands is often in conflict with effective mosquito control strategies. Annually abundant pest and vector mosquito populations bring with them the risks of disease caused by Ross River virus and Barmah Forest virus. Large scale wetland rehabilitation projects are increasing the availability of productive mosquito habitat while also providing refuge for known reservoir hosts (e.g. macropods, birds) of mosquito-borne viruses. Balancing the desire for environmental conservation with the need to protect the health of human communities requires integrated urban design strategies combined with targeted research. While broadscale mosquito control activities are restricted due to unresolved issues associated with potential ecological impacts, local authorities are looking to use planning instruments to minimize the impacts of local mosquitoes by requiring mosquito risk assessments to be conducted by developers, placing stringent controls on constructed water bodies and the incorporation of buffer zones between residential allotments and mosquito habitats. However, the effectiveness of these strategies is often site-specific and is determined by the local mosquito fauna. Potentially important onsite mosquito habitats are also being created through Water Sensitive Urban Design strategies intended to increase water conservation through above- and below-ground water treatment and storage.

Some background to the presentation is presented here.

Following this presentation, an article of mine was published on The Conversation website. “Using urban planning to reduce mosquito-borne disease” discusses many of the issues surrounding urban development and the increasing risk of mosquito-borne disease in Australia.