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.

Summer summary of mosquito media madness

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Summer is always a busy time for me. As well as plenty of time sloshing about in the wetlands, there is often lots of interest from mosquito-curious media. There has been some intense bursts of activity in previous summers but the 2015-2016 was particularly interesting.

I certainly covered some new ground this summer. I responded to over 160 individual media requests in the past 6 months. From flies and food safety to the emergence of Zika virus. Here is a wrap from my media adventures and some valuable lessons learned for future science and public health communication.

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The good news of new virus discoveries

Usually, the discovery of a new mosquito-borne virus brings with it new concern for public health. This time though, there was some good news.

Towards the end of 2015, a paper reporting on a collaborative research project between University of Queensland, QLD Health and University of Sydney was published in Virology. This was the first publication detailing the discovery of Parramatta River virus, an insect specific virus that exclusively infects the mosquito Aedes vigilax. This virus does not infect people and poses no health risk.

A joint media release was issued by University of Queensland and University of Sydney and there was plenty of media attention. Not surprising given the usual negative associations with mosquito-borne pathogens!

There were dozens of articles, much of the attention focused on the team at University of QLD. Dr Jody Hobson-Peters was kept busy with local media including ABC and Brisbane Times. It was a great experience sharing the research with colleagues in Queensland, particularly great seeing so much exposure for PhD student Breeanna McLean and her newly published research.

I was surprised at how little attention there was in the news from Sydney media. The lesson here though was more about bad timing than uninteresting research. A couple of weeks after the initial media release, I forwarded around a few emails and sent out a couple of tweets and next thing you know, we made the front page of the local newspaper, the Parramatta Advertiser (see above). It was some great local coverage, not only about the virus discovery but it also provided an opportunity to raise awareness of mosquitoes and mosquito-borne disease on the eve of summer!

Lesson learned: A good reminder that if your research isn’t picked up immediately, give it another shot a few weeks later. Timing may make all the difference but perseverance does too!

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To stop sickness, swat or spray

Just in time for Christmas lunch and summer holiday picnics, I published an article on flies and food safety at The Conversation. I really expected this article to slip under the radar of most people. Coming out on Christmas eve doesn’t seem likely many would be clicking about on the internet but within a few days over 600,000 people had clicked on the piece!

Many of those clicks were thanks to the article being shared by IFLS but there was also plenty of interest from local media and I was busy with interview requests from ABC Local Radio across the country. Who doesn’t love hearing about how flies poop and vomit on your food? I was even interviewed by Grey Nomad Magazine!

Lesson learned: Applying a little science to seasonal urban myths and common uncertainties can prove popular and may be a good opportunity to promote a little science!

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Rain, rain everywhere with mozzies soon to come

With all the talk of El Nino and predictions of a hot and dry summer for the east coast of Australia, the summer was actually reasonably mild and extremely wet. Sydney was particularly battered by a series of storms and intense rainfall early in 2016.

More water generally means more mosquitoes. In response to the rain, many media outlets were interested in chatting about the prospects of a bumper mosquito problem. As well as talking about the prospects of an increase in mosquito-borne disease risk, it was a great opportunity to talk about personal protection measures.

There were some radio, print and tv spots that provided opportunities to talk about how to choose and use the right repellents.

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In 2015 I published a paper in the Medical Journal of Australia explaining that health authorities need to provide more guidance on how the community can get mosquito repellents working more effectively.

Typical health warnings and media release from health authorities (usually limited to grabs on news bulletins) but when there is an opportunity to do longer form radio interviews, there is a chance to put an emphasis on aspect of public health messages. The hook to get these longer spots is giving more than just warnings, by mixing up some interesting things about mosquitoes, you can catch a little extra attention and sneak in the public health messages between the fun and fascinating facts about mosquitoes!

One news outlet was really insistent in grabbing a hold of me for some comments ahead of the evening bulletin. They even sent a crew to meet me in the city while I was taking the kids along to the Sydney Festival!

Lesson learned: When doing tv for the evening news, it is ok to wear a t-shirt, shorts and runners just so long as you have a rain jacket handy to make you like like you could have just stepped straight out of the wetlands!

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From African forests to South American cities

While many of us were keeping our eyes on the developing outbreak of mosquito-borne Zika virus in South America towards the end of 2015, it wasn’t until February 2016 that the situation really grabbed the attention of the world’s media.

In late January, I published a piece at The Conversation titled “Does Zika virus pose a threat to Australia?” It prompted a little interest but it was the media conference coordinated by University of Sydney Media and Communications together with Australian Science Media Centre (AusSMC) that coincided with the announcement of the World Health Organization that the Zika virus outbreak was a Public Health Emergency of International Concern.

Together with colleagues from the University of Sydney’s Marie Bashir Institute of Infectious Disease and Biosecurity, I spoke at a media conference broadcast nationally on ABC News 24. There was a huge amount of media stories stemming from this media conference with over 500 individual articles identified across radio, tv, print and online. During the days and weeks following, I felt like I was spending more time at the ABC studios in Ultimo than I was in our lab! There were days when I spent hours on the phone doing radio interviews.

There were a couple of great longer form interviews that I really appreciated the opportunity to contribute to such as ABC Radio National’s Health Report and Rear Vision. There were also a couple of podcasts too, check out Science on Top and Flash Forward.

This flood of media requests also exposed me to a few more new experiences. There were live tv appearances on Sunrise, ABC News 24 and Sky News but probably one of the most interesting was my spot on Channel Ten’s The Project. It was interesting for a number of reasons.

Firstly, I was warned early on that one of the guests on the panel was comedian Jimmy Carr, a somewhat controversial figure notorious for jokes a little too close to bad taste. I’m not typically one to play the “wacky scientist” during interviews but what I was most cautious of was not being seen to be treating a very serious disease outbreak too lightly. I was determined to play the straight guy. In the end the interview turned ok but there were a couple of awkward moments that, luckily, ended up being edited out.

Secondly, simply doing the interview was unusual. It was a pre-recorded interview with me in a tiny room at the Channel Ten studio in Sydney and the panel in the Melbourne studio. I was sitting in front of a green-screen, staring down the camera with an earpiece blasting away in my ear. I have done live crosses before but they’re all been one-on-one interviews. This time it was with the panel and I found it incredibly difficult to get the feel for each of the panelists when they were asking questions. Missing that eye-to-eye contact was a disconcerting experience. Luckily, all turned out well in the end.

Lesson learned: Lots (I mean LOTS) learned while dealing with the interest in Zika virus! Probably another post in itself…but I would say that managing this volume of media wasn’t easy and it did eat up a lot of time (even though communicating public health messages is central to my “day job”) but this was important work.

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A morning with Dr Karl!

When it comes to science communicators in Australia, there are few with a higher profile than Dr Karl Kruszelnicki. We’d spoken on a number of occasions about mosquitoes but I’d never actually met him in person before. “Dr Karl” invited me to hang out for a morning recording interviews for ABC News 24, ABC Local Radio and also guest on his national “Science Talk” segment on Triple J’s Mornings Show with Zan Rowe.

The experience of a behind-the-scenes perspective on Karl’s hectic schedule and how he manages the frenetic pace of work at the ABC was an eye opener. Doing the hour long segment on Triple J was great, enlightening to get questions from a slice of the Australian community I don’t usually cross paths with when doing the usual community engagement. I good reminder of just how much anxiety there can be within the community when news of international disease outbreaks occur. Not surprising given the thousands of Australians travelling to South America each month….with more to come later this year when the Rio Olympic Games kick off!

You can listen to the segment here and you can also follow Dr Karl on Twitter.

Lesson learned: From a public health perspective, this is a great reminder that the concerns and anxieties around infectious disease can change depending on the sector of the community you’re dealing with. The core messages may remain the same but you’ll always need to consider your audience when fine tuning your public health messages.

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So, was all this worth it?

It was stressful. It was fun. It eroded much of my time that may have been spent in other ways but I see this as “doing my job” perhaps a little more than pure research scientists do. But how does all this convert into tangible metrics. How do you measure the reach and economics of all these media activities?

I’m fortunate to be supported by the University of Sydney media and communications team that helps out by providing some data on the metrics of my media activities each summer. What was all this time and effort worth?

Between November 2015 and Match 2016, I was quoted in over 160 media items. This adds up to a cumulative audience of around 8.9 million people, that is quite some reach! How much was it worth? Based on current advertising rates, about $1.6 million.

I’ve written before about how we can better value science and public health communication. Collecting these types of metrics can be useful for a range of purposes. Recently, I’ve been including media engagement as an “in kind” contribution to grant applications with valuation calculated on average media coverage that may be expected.

The lesson here is to take the time to record your media activities, not just so you have a list to demonstrate quantity but also so you can assess audience and value to your media activities. Work with your media and communications departments to see what extra information you can collect.

Got any other tips? Share them via Twitter!

 

 

 

 

 

Can social media help translate research to practice and promote informed public health messages?

I’m a Senior Investigator with the Centre for Infectious Diseases and Microbiology – Public Health. One of our primary focuses is translating research into improved public health outcomes. With NSW Population Health and Health Services Research Support Program assisting our work, we’re exploring new ways to achieve this objective. My experience of using social media was selected to be showcased among other case studies in 2015. 


Nuisance-biting mosquitoes and mosquito-borne disease are concerns for local authorities in Australia. 2015 saw the largest outbreak of mosquito-borne Ross River virus disease for more than 20 years with over 9,500 cases nationwide. In NSW, there were 1,633 cases compared to the annual average since 1993 of 742 cases per year. Notwithstanding the current outbreak, other endemic, as well as exotic, mosquito-borne pathogens represent future threats to public health.

As there is no large-scale mosquito control program in NSW, reducing the contact between mosquitoes and people is primarily achieved through the promotion of personal protection measures. NSW Health promotes the use of topical insect repellents in combination with behavioural change to avoid natural mosquito habitats and the creation of mosquito habitats around the home. This information is typically provided in the form of posters, brochures, online factsheets, and seasonal or outbreak-triggered public health messages issued by Local Health Districts or the NSW Ministry of Health.

With the emergence of new communications technologies, particularly the rise in popularity of social media, there are new opportunities for public health communications.

The aim of the current research was to determine the reach of public health messages through social media by tracking engagement, audience and relative value as assessed by media monitoring organisations and metrics provided by hosting services of social media platforms.

Assessing activities and processes

Dr Cameron Webb (CIDM-PH) has focused much attention on filling the gaps between current public health messages and findings from recent research into topical mosquito repellents.[1] For example, while public health messages provide accurate information on the insect repellents that provide the best protection, there is a paucity of information provided on how best these products should be used by individuals and those they care for.

Dr Webb’s engagement with mass media, online media (e.g. The Conversation), a personal blog (e.g. Mosquito Research and Management) and social media (e.g. Twitter) has resulted in substantial exposure of focused and informed public health messages. From mid-2014 through to the end of 2015, Dr Webb participated in over 80 mass media articles and interviews in print, online, radio and television media with public health information reaching an estimated audience of over 10 million people.[2] The focus of his messaging around mosquito-borne disease was to highlight the best way for the community to choose and use mosquito repellents; stressing the importance of active ingredients and application methods. This fills a gap in the current provision of public health information while also augmenting public health alerts and messages associated with the 2015 outbreak of Ross River virus disease.

Social media has become a “go to” source of information for much of the community. Information shared on Facebook, Twitter, Instagram, and YouTube has the potential to shape the habitats and behaviour of the community. Dr Webb is active on Twitter (currently followed by over 4,500 people); he uses the platform to engage with the social media accounts of journalists and broadcasters to establish a voice of authority in the field of mosquito-borne disease prevention and extend the reach and exposure of public health messages broadcast through mass media. Using Twitter to share links to informed articles following interviews reached hundreds of thousands of people by being shared by the social media accounts of journalists, media outlets, government organisations and community groups. During the 2014-2015 summer, tweets by Dr Webb reached an estimate 1.28 million people.[3]

Dr Webb regularly writes open access articles on his website, attracting around 250 daily visitors with over 117,000 article views.[4] In addition to his personal website, Dr Webb regularly contributes articles to The Conversation (a website for academics to share expert opinion and write about their latest research). His articles have attracted over 120,000 readers. However, one article “why mosquitoes seem to bite some people more” (published 26 January 2015) has alone been read by over 1.3 million people.[5] This “non-scholarly” writing not only establishes CIDM-PH scientists as authorities in public health matters but can also assist in directing the public to official health guidance provided on official websites and other sources.

Dr Webb’s activities provide a framework for how health authorities may engage with social media to extend public health messages. Organisations or individuals can connect health authority information with the community through media outlets. He has been invited to share his experiences in this field at local and international conferences and workshops including those coordinated by the Public Health Association of Australia, Australian Entomological Society and Entomological Society of America. In addition, Dr Webb has been invited to provide lectures on the benefits of social media for public health advocacy to undergraduate and post-graduate students at the University of Sydney.

While traditional messaging provided by health authorities will remain a staple in public health campaigns, social media provides a connection between traditional and emerging media and communication organisations. This increased connectivity between public health advocates, the media and community has the potential to greatly improve the awareness of mosquito-borne disease and increase the rate of uptake and application of strategic personal protection measures.

References

  1. Webb C.E. (2015). Are we doing enough to promote the effective use of mosquito repellents? Medical Journal of Australia, 202(3): 128-129.
  2. Estimated audience reported by Kobi Print, Media and Public Relations, University of Sydney, 23 April 2015, based on data provided by media monitoring organisation isentia.
  3. Estimated from total “tweet impressions” for the period October 2014 through April 2015 provided by Twitter Analytics (https://analytics.twitter.com/user/Mozziebites/home accessed 30 April 2015)
  4. Data provided by WordPress statistics (accessed 18 December 2015)
  5. Data provided by The Conversation metrics (accessed 18 December 2015)

This article was originally published by NSW Health showcasing some of the work within the NSW Population Health and Health Services Research Support Program. You can see the original article here.

Beware the thick skinned bed bugs (they’re beating our bug sprays)

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Think you’re got thick skin? You may be able to brush off the odd insult but for bed bugs, their thick skin can ward off fatal doses of insecticides! This is just one way they’re beating our commonly used bug sprays.

The resurgence of bed bugs over the past couple of decades has been great fuel for media and pest control companies alike. From Paris to London and New York to Sydney, infestations in all forms of accommodation has made headlines.

Eradicating an infestation of bed bugs can be tricky, tricky and expensive. While control within the hospitality industry is improving, the impacts of bed bugs are now being felt in lower socioeconomic groups in the community. There are often financial barriers to effectively controlling infestations and controlling infestations is not getting any easier.

Working out why bed bugs are hard to kill

David Lilly is currently a postgraduate student in our lab undertaking his PhD with the University of Sydney. He has been doing some great work and its wonderful as a supervisor to see him starting to publish some of his research as he approaches the end of his candidature.

We’ve already published some research on bed bugs and insecticide resistance and the role of metabolic detoxification in driving this resistance (you can read about that work via at Entomology Today). However, some of the most exciting research has just been published and indicates that “thicker skinned” bed bugs are more resistant to pyrethroid insecticides.

It is one thing to demonstrate insecticide resistance in a pest but understanding why that resistance occurs is critical if we’re to develop more effective strategies to control bed bugs.

This project was inspired by a study that demonstrated that mosquitoes resistant to insecticides had thicker cuticle. Could the same phenomenon occur in bed bugs?

Working with the Australian Centre for Microscopy & Microanalysis at The University of Sydney, we were able to capture images of cross-sections of legs from resistant and susceptible strains of bed bugs. Measuring the cuticle thickness at various points and comparing those between the two strains of bed bugs allowed an assessment of changes in cuticle.

Those bed bugs resistant to insecticides had thicker cuticle. In fact, the cuticle of the resistant bed bugs was around 15% thicker. Thicker the cuticle, the tougher it is for insecticides to penetrate.

Given human’s propensity to use insecticides, it is little wonder our most loathsome pests, such as mosquitoes and bed bugs, are developing resistance. While there really aren’t many other options available to control bed bugs, insecticides will remain part of our pest control tool kit. Alternative strategies are always being considered but while insecticides remain, we need to be mindful of the development of resistance and ways we can slow (or overcome) that process.

Bed bug’s thick skins grab the media’s attention

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The research has already received international media coverage thanks to the fantastic team at University of Sydney Media and Communications team. A quick “google news” search turns up over 70 news items reporting on the paper! You can catch up with coverage at Popular Science (Australia), Wired, USA Today, Daily Mail, Sydney Morning Herald, BBC, Newsweek, Gizmodo and Mirror.

The abstract for our paper is below:

Thickening of the integument as a mechanism of resistance to insecticides is a well recognised phenomenon in the insect world and, in recent times, has been found in insects exhibiting pyrethroid-resistance. Resistance to pyrethroid insecticides in the common bed bug, Cimex lectularius L., is widespread and has been frequently inferred as a reason for the pest’s resurgence. Overexpression of cuticle depositing proteins has been demonstrated in pyrethroid-resistant bed bugs although, to date, no morphological analysis of the cuticle has been undertaken in order to confirm a phenotypic link. This paper describes examination of the cuticle thickness of a highly pyrethroid-resistant field strain collected in Sydney, Australia, in response to time-to-knockdown upon forced exposure to a pyrethroid insecticide. Mean cuticle thickness was positively correlated to time-to-knockdown, with significant differences observed between bugs knocked-down at 2 hours, 4 hours, and those still unaffected at 24 hours. Further analysis also demonstrated that the 24 hours survivors possessed a statistically significantly thicker cuticle when compared to a pyrethroid-susceptible strain of C. lectularius. This study demonstrates that cuticle thickening is present within a pyrethroid-resistant strain of C. lectularius and that, even within a stable resistant strain, cuticle thickness will vary according to time-to-knockdown upon exposure to an insecticide. This response should thus be considered in future studies on the cuticle of insecticide-resistant bed bugs and, potentially, other insects.

The full citation is: Lilly DG, Latham SL, Webb CE, Doggett SL (2016) Cuticle Thickening in a Pyrethroid-Resistant Strain of the Common Bed Bug, Cimex lectularius L. (Hemiptera: Cimicidae). PLoS ONE 11(4): e0153302. doi:10.1371/journal.pone.0153302

Download the paper for free directly from PLoS ONE!

Oh, and if you’re worried about picking up bed bugs on your next holiday, here are some tips!

 

Zika virus: Resources, references and recommendations

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The following is a collection of almost 100 links to news stories, resources, references and recommendations associated with mosquito-borne Zika virus and the current outbreak in the Americas.

What is Zika? What are the health threats and why an outbreak now?

Zika virus (CDC). Essential resource. Click.

Zika virus (WHO). Essential resource. Click.

Zika virus spreading explosively, says World Health Organisation (The Guardian). Coverage of statement by WHO Director General that the explosive outbreak of Zika virus in the Americas as “deeply concerning” and that an emergency committee has been convened. Click.

WHO Director-General summarizes the outcome of the Emergency Committee regarding clusters of microcephaly and Guillain-Barré syndrome (WHO). Click.

Zika virus declared a global health emergency by WHO (ABC News). Click.

Zika Virus Spreads to New Areas — Region of the Americas, May 2015–January 2016 (CDC). Click.

WHO early response to Zika virus praised by Australian experts (The World Today). Click.

First report of autochthonous transmission of Zika virus in Brazil (Memórias do Instituto Oswaldo Cruz). Click.

How a Medical Mystery in Brazil Led Doctors to Zika (New York Times). A summary of how health officials investigating a spike in cases of birth defects put together the link to a mosquito-borne disease. Click.

Explainer: where did Zika virus come from and why is it a problem in Brazil? (The Conversation). A good, brief summary of the emergence of Zika virus in Brazil and the health risks it poses. Click.

Zika virus outbreak: What you need to know (New Scientist). A good summary of issues associated with Zika virus outbreak. Click.

Zika outbreak: What you need to know (BBC). A good summary of what is known of Zika virus and its health risks. Click.

What to Know About Zika Virus (The Atlantic). Click.

Zika virus, explained in 6 charts and maps (Vox). Useful collection of infographics on Zika virus, current and historic outbreak distributions and health impacts. Click.

An Illustrated Guide To The Zika Outbreak (Huffington Post). Click.

Why it’s wrong to compare Zika to Ebola (The Conversation). Whats the difference between Ebola and Zika viruses? What are the implications of outbreaks and declarations of public health emergencies? Click.

Zika fever: panic won’t help us (The Guardian). Editorial highlighting the horror and unexpectedness of the Zika virus outbreak in Brazil and how we should move forward in mosquito control. Click.

What we still don’t know about Zika virus (Mashable). There are plenty of gaps in our understanding of Zika virus. Click.

The human cost of Zika is clear, but will Brazil’s economy suffer too? (The Conversation). Outbreaks of infectious diseases can have greater impacts than the human illness alone. Click.

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Zika virus and its vectors

Mosquitoes: The Zika vector (Radio National). Why do we need to know how many mosquitoes can spread Zika virus and what is it about the mosquitoes that do that make them such an important pest? Click.

Natural-born killers: mosquito-borne diseases (SMH). What is it that makes mosquitoes such effective vectors of pathogens? Click.

Zika Virus in Gabon (Central Africa) – 2007: A New Threat from Aedes albopictus? (PLOS Neglected Tropical Diseases). Click.

Oral Susceptibility of Singapore Aedes (Stegomyia) aegypti (Linnaeus) to Zika Virus (PLOS Neglected Tropical Diseases). Click.

Aedes (Stegomyia) albopictus (Skuse): A Potential Vector of Zika Virus in Singapore (PLOS Neglected Tropical Diseases). Click.

Potential of selected Senegalese Aedes spp. mosquitoes (Diptera: Culicidae) to transmit Zika virus (BMC Infectious Diseases). Click.

Genetic Characterization of Zika Virus Strains: Geographic Expansion of the Asian Lineage (PLOS Neglected Tropical Diseases). Click.

Molecular Evolution of Zika Virus during Its Emergence in the 20th Century (PLOS Neglected Tropical Diseases). Click.

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The spike in cases of microcephaly and its suspected links to Zika virus infection of those pregnant has been raising greatest concern. (Image: BBC)

Zika virus, pregnancy and microcephaly

Possible Association Between Zika Virus Infection and Microcephaly — Brazil, 2015 (CDC). Click.

Microcephaly in Brazil: is it occurring in greater numbers than normal or not? (Virology Down Under). Great post highlighting the gaps in our understanding of links between microcephaly and Zika virus. Click.

Proving that the Zika virus causes microcephaly (The Conversation).  What questions must be answered to confirm a link between Zika virus and microcephaly. Click.

Interim Guidelines for Pregnant Women During a Zika Virus Outbreak — United States, 2016 (CDC). Click.

CDC: Link between Zika, microcephaly looks “stronger and stronger” (Reuters). Click.

Facts about Microcephaly (CDC). What are the impacts, causes and treatments associated with microcephaly? Click.

Zika virus outbreak raises Pacific, Americas travel concerns for pregnant women (Stuff NZ). Implications for those travelling in Pacific while pregnant. Click.

Safely avoiding mosquito bites when pregnant (Mosquito Research and Management). My tips on safe and effective avoidance of mosquito bites while pregnant. Click.

13 Things Pregnant Women Should Actually Know About Zika (Buzzfeed). Some good advice, most importantly, don’t panic. Don’t even panic if you’re pregnant and bitten by a mosquito. Click.

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Zika virus and the threat to Australia

Does Zika virus pose a threat to Australia? (The Conversation). An overview of why, and why not, Zika virus poses a risk to Australia. Click.

The Threat to Australia: The Rise Of Zika Virus (Popular Science). Article from 2014 highlighting potential risk to Australia of Zika virus following detection of imported cases. Click.

Zika Virus Explained: Aussie Mozzies, Bali Risks And Pregnancy (Huffington Post). Good summary of risks posed to Australia and Australian travellers. Click.

Zika virus: Risk of a widespread outbreak in Australia ‘low’, experts say (ABC News). A summary of reasons why there won’t be a major outbreak of Zika virus in Australia. Click.

Zika talkback with Dr Karl on Triple J (ABC). I join Dr Karl for talkback on Zika virus, advice to travellers and the risks of outbreak in Australia. Click.

Zika virus alert (NSW Health). Factsheet on Zika virus and risk to NSW. Click.

Little chance of Zika outbreak in NSW (Sky News). There is unlikely to be a major outbreak of Zika virus across Australia’s most populated region. Click.

Two Aussies confirmed with Zika as US records first case of virus transmitted through sex (The Mercury). Click.

Zika virus mosquitoes found in Sydney: Airport increases insecticide spraying of incoming passengers (Daily Telegraph). Report of recent detection of Aedes aegypti at Sydney airport by Department of Agriculture and Water Resources. Click.

Queensland announces $1.4 million program to fight Zika. (Brisbane Times). Queensland authorities announce response plan; increasing monitoring and research into Zika virus.  Click.

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Zika virus entering Australia

Zika virus and Travel Alert for Australians (Smart Traveller). Click.

Imported Zika Virus Infection from the Cook Islands into Australia, 2014 (PLOS Current Outbreaks). Click.

Zika Virus Infection Acquired During Brief Travel to Indonesia (Am J Trop Med Hyg). Published report from 2013 of Australian traveller exposed to Zika virus in Indonesia. Click.

Aussie diagnosed with Zika after Bali monkey bite, experts warn of missed cases (SMH). Report of 2015 case os suspected infection following monkey bite in Bali. Click.

Zika Virus Infection In Australia Following A Monkey Bite In Indonesia (Southeast Asian Journal of Tropical Medicine and Public Health). Abstracted from published case report of suspected Zika virus infection following monkey bite. Click.

Six cases of Zika virus in Australia last year as pregnant women warned not to travel (SMH). Summary of recent imported cases of Zika virus infection in Australian travellers. Click.

Health Department confirms WA Zika case (The West Australian). Report of imported case of Zika virus infection in returning traveller to Western Australia. Click.

Zika virus: Queensland woman, child confirmed as contracting illness (ABC News). Imported cases of Zika virus infection with travellers returning to QLD from El Salvador. (ABC News). Click.

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Zika outbreaks in the Pacific

Zika Virus Outside Africa (Emerging Infectious Diseases). Summary of outbreaks in regions outside Africa with specific discussion of the first outbreak in Pacific. Click.

Zika Virus Outbreak on Yap Island, Federated States of Micronesia (New England Journal of Medicine). Click.

Zika virus: following the path of dengue and chikungunya? (The Lancet). Good paper, including useful maps, of activity of three critical mosquito-borne pathogens. Click.

Rapid spread of emerging Zika virus in the Pacific area (Clinical Microbiology and Infection). Publication reporting on the 2013 outbreak of Zika virus in the Pacific. Click.

Notes on Zika virus – an emerging pathogen now present in the South Pacific (Australian and New Zealand Journal of Public Health). An article assessing the risks of Zika virus to New Zealand. Although no suitable vectors exist there, a relatively larger volume of infected travellers would be expected to occur given the strong links to Pacific Islands. Click.

Tonga declares Zika outbreak (Sky News). Zika is impacting more regions than the Americas in 2016. Click.

Australia to help Pacific fight Zika (SBS News). How can Australian authorities take their expertise in mosquito monitoring, mosquito control and vaccine development to assist outbreak of Zika virus. Click.

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Zika virus and sex: An unusual route of transmission

Probable Non–Vector-borne Transmission of Zika Virus, Colorado, USA (Emerging Infectious Diseases). First documented case of transmission of Zika virus through direct contact between people. Click.

Potential Sexual Transmission of Zika Virus (Emerging Infectious Diseases). Publication from 2015 on suspected sexual transmission of Zika virus. Click.

Zika virus infection ‘through sex’ reported in US (BBC). Suspected case of sexually transmitted Zika virus in Texas in 2016. Click.

CDC: To avoid Zika exposure, consider no sex (The Washington Post). Coverage of CDC guidance on avoiding sexual transmission risk of Zika virus. Click.

Interim Guidelines for Prevention of Sexual Transmission of Zika Virus — United States, 2016 (CDC). Click.

Zika: Why the virus isn’t an STI despite being passed on after sexual contact (Independent).  Only where sex is the predominant route of transmission, and the infection is maintained in the human population by sexual transmission, is a pathogen considered a STI and that definition does not apply to Zika virus. Click.

Brazil finds Zika in saliva, urine; expert warns against kissing (SMH). Detection of Zika virus in saliva and urine doesn’t necessarily mean these are pathways of transmission. Authorities advising against kissing? Click.

Zika and the 2016 Rio Olympics

Zika Outbreak Means It Is Now Time To Cancel Rio Olympics (Forbes). Is the threat of Zika virus really so great that the Rio Olympics should be cancelled? Click.

NYU Bioethicist, Amid Zika Threat, Wants to Reschedule Rio Olympics: ‘What the Hell’s the Difference?’ (New York Magazine). With so many unanswered questions, and little confidence the outbreak is under control, is it really ethical to go ahead with the Rio Olympics? Click.

Brazil minister says no plans to cancel Rio Games (AP). Click.

Zika virus will not hamper Rio Olympics says IOC president Thomas Bach (ABC News). Click.

IOC says it will issue advisory on Zika virus spreading across South America ahead of Rio Olympics (ABC News). Click.

Zika crisis and economic woes bring gloom to Brazil’s Olympic buildup (The Guardian). Click.

Zika scare: Olympic athletes need mosquito nets as Bushman sponsors team (SMH). Click.

Zika Virus Rio Olympics: How Australian Athletes Will Fight Potential Infection (Huffington Post). Click.

Bushman named as official insect repellent of Australian Olympic team (mUmBRELLA). One of Australia’s leading mosquito repellent manufacturers to support the athletes and officials travelling to Rio Olympics. Click.

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Battling mosquitoes and the Zika virus outbreak

How Can We Slow The Epidemic Of Zika Infections? (Forbes). Now that the outbreak of Zika virus has been documented, what strategies are available to slow the spread and increasing numbers of cases? Click.

The world needs a Zika vaccine: Getting one will take years (STAT). We won’t have a Zika virus vaccine anytime soon. Here is an explanation why. Click.

Brazil Zika virus: ‘War’ declared on deadly mosquitoes (BBC). How are authorities battling the outbreak of Zika virus in Brazil? Click.

Mosquito Wars Update: Would You Choose GMO ‘Mutants,’ Pesticides Or Dengue And Zika Viruses? (Forbes). The outbreak of Zika virus has focused the attention of health authorities on options for future mosquito-borne disease management strategies. Click.

Brazil sends in 200,000 soldiers to stop the spread of the Zika virus outbreak which has seen huge numbers of babies born with small heads and cast a shadow over the Olympics (Daily Mail). Click.

Here’s what it will take to stop the Zika virus (Vox). Summary of critical issues to address to better understand and stop the Zika virus outbreak. Click.

Curbing Zika Virus: Mosquito Control (Popular Science). Well supported article on options for mosquito control and mosquito-borne disease management. Click.

7 ways the war on Zika mosquitoes could be won (New Scientist). Overview of the different approaches available to beat the Zika virus outbreak and mosquito-borne disease more generally. Click.

In Australia, a New Tactic in Battle Against Zika Virus: Mosquito Breeding (New York Times). Overview of emerging technologies developed in Australia to battle dengue but could be incorporated into the Zika virus response. Click.

Zika virus: pesticides are not a long-term solution says leading entomologist (The Guardian). Spraying insecticides can sometimes be a blunt instrument unless there is an understanding of where best to target mosquito populations. Click.

Zika outbreak revives calls for spraying with banned pesticide DDT (STAT). Outbreaks of mosquito-borne disease often prompt calls to return to DDT as teh insecticide of choice to control mosquitoes. Click.

Insecticide to be sprayed inside planes from Zika affected regions (The Guardian). Aircraft should already be treated with insecticides to stop movement of mosquitoes from one country to the next, hitchhiking in planes but efforts have been boosted in wake of Zika virus fears. Click.

Bats and Mosquitoes

Illustration by Golly Bard

Be careful what you wish for

Let’s Kill All the Mosquitoes (Slate). Emergence of another mosquito-borne disease, another opportunity to call for killing mosquitoes off completely. Click.

Why Eradicating Earth’s Mosquitoes To Fight Disease Is Probably a Bad Idea (Vice). Don’t be so sure that eradicating mosquitoes is the answer, or at least it won’t have consequences. Click.

Would it be wrong to eradicate mosquitoes? (BBC). What could be the unexpected consequences of sending mosquitoes extinct? Click.

Sights on world’s deadliest animal as Zika virus spreads (The New Daily). Wiping out all mosquitoes is probably a bad idea but perhaps we could knock off just a few and greatly improve the health of the planet? Click.

There’s one (or more) in every crowd…

Is Zika Virus the Next Tool For Forced Sterilization, Vaccination and Depopulation? (Activist Post). Oh boy. Click.

Health experts slam anti-vaxxers’ zika virus conspiracy theory as ‘absurd’ (News.com.au). No, immunization programs didn’t cause the Zika virus outbreak and increases in microcephaly. Click.

Concerning Correlation: GMO Mosquitoes Caused Zika Virus Outbreak? (21st Centuray Wire). Bonkers. Click.

No, GM Mosquitoes Didn’t Start The Zika Outbreak (Discover Magazine). Wonderful article debunking one of the most common conspiracy theories associated with the Zika virus outbreak. Click.

Got any more useful links? Tweet them through to me!

Photo of sign from Zika Forest taken from here.

Should we start pulling out mangroves to save our wetlands?

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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.

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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.

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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.

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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.

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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.

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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.

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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.

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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.

 

Safely avoiding mosquito bites when pregnant

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Hundreds of millions of people fall ill due to mosquito-borne pathogens every year but the recent rise in birth defects associated with Zika virus emerging in the Americas has health authorities on alert.

Zika virus is transmitted by mosquitoes, primarily by the Yellow Fever mosquito, Aedes aegypti. Since its discovery in Africa around 70 years ago it has avoided the public health spotlight due to the relatively mild illness it causes. Throughout Africa and Asia it is overshadowed in importance by the diseases caused by malaria parasites as well as dengue and chikungunya viruses.

For background on the rise of Zika virus, see my article for The Conversation.

Zika and the health risks to those pregnant and their unborn children

While Zika virus has yet to be fully confirmed as the causative agent in birth defects (such as microcephaly), there is clearly enough concern among health authorities in many parts of the world to issue warnings to those pregnant to avoid travel to countries experiencing an outbreak of Zika virus.

Authorities in Columbia and El Salvador have even gone so far as to advise residents to avoid falling pregnant for up to two years.

The Australian Government issued the following advice via their SmartTraveller website:

“Until more is known about Zika virus, and taking a very cautious approach, we advise women who are pregnant (in any trimester) or who plan to become pregnant to consider postponing travel to any area where Zika virus transmission is ongoing. If you do decide to travel, talk to your doctor first and strictly follow steps to prevent mosquito bites during your trip.”

For many, the option of not travelling will be easy. But what if you still want to travel? What if you’re doing business in some of these countries? What if you need to travel to visit family? Cancelling a trip isn’t always the easiest options.

Reducing risk of mosquito-borne disease while travelling

Irrespective of the current Zika outbreak, travelling while pregnant brings various health and safety risks.  Other mosquito-borne diseases, such as malaria and dengue, also pose a risk to pregnant women and their unborn children. These serious risks existed long before Zika virus grabbed the public health spotlight.

Unfortunately, there is no vaccine currently available for Zika virus. Vaccines are in development for dengue viruses and anti-malaria drugs are available so consult your local travel health clinic.

While travelling, staying indoors as much as possible, particularly air-conditioned accommodation, will greatly reduce exposure to mosquitoes. This may not be how you expected to spend your time during a South American holiday!

Many people associate mosquito-borne disease with wetland or jungle environments but as Zika virus is spread by mosquitoes found in urban habitats (e.g. water-filled containers), travellers should not be complacent if only visiting cities. Some of the biggest recent outbreaks of mosquito-borne disease have been in major metropolitan regions in the Americas and Asia.

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Mosquito control in Brazil, a striking image of the battle against container-inhabting mosquitoes (Image: Ernesto Benavides via International Business Times)

If you’re staying at a high end resort, chances are there will be a well established insect control program. This typically includes widespread spraying for insecticides to knock down any mosquito populations. This may not completely remove risk but it will substantially lower potential exposure to mosquitoes. Again, don’t be complacent and take special care to avoid mosquitoes if taking a day trip to local villages or other tourist attractions.

Sleeping under a bed net is usually recommended in regions where malaria is an annual problem but this may not offer that much protection against Zika virus as the mosquitoes that spread the virus primarily bite during the day. If you’re planning on taking some afternoon naps, make sure it is under a bed net. A range of insecticide treated bed nets are available from your local camping store.

There is also an ever increasing range of “pre-treated” insect repellent clothing but evidence is scarce on just how effective these are at preventing bites. Treating clothing with insecticide (e.g permethrin) yourself would be a better option but don’t expect that wearing treated clothing means you don’t have to put insect repellents on exposed skin.

Safe and effective use of mosquito repellents

There will be anxiety among many about using insect repellents while pregnant. Are they safe? Will they impact the baby?

Without doubt, the most commonly used, safe and effective mosquito repellents is DEET (I’ve written about these repellents extensively, see here and here but I’ll summarize below). This is found in lots of major commercial brands and is a mainstay in the recommendations issued by health authorities the world over. Problem is, it can be hard to find information on how to choose and use the repellent that’s right for you and your situation.

The first point to remember is that the the strength of the formulation determines how long you’re protected against mosquito bite, not how many mosquitoes are kept away. For example, a 10% DEET based repellent may provide 2h protection, a 20% formulation may provide 4h protection. When choosing a repellent, think about how long you need protection for and how frequently you’re happy to reapply.

Secondly, the repellent must be applied as an even coverage on all exposed skin. If there are “gaps” in the application, mosquitoes are sneaky enough to pick a spot to bite. In the case of the mosquitoes that spread Zika, dengue and chikungunya viruses, pay special attention to application around the lower legs and feet, that’s where they like to bite.

Be sure to reapply repellent after swimming or sweaty exercise too.

There is no need to apply mosquito repellents to skin under clothing.

Are repellents safe to use when pregnant?

Health authorities and regulatory agencies rarely provide specific warnings on the use of insect repellents by those pregnant. While there haven’t been many clinical trials, these papers (here and here) demonstrate a lack of documented significant health risk associated with the used of DEET-based repellents. Most notably, a study of almost 900 women using mosquito repellent in the second or third trimester and no adverse neurologic, gastrointestinal, or dermatologic effects were observed in women or their infants for a year after birth.

It is important to balance the distinct lack of evidence of major health risks associated with repellents to the rapid rise in microcephaly in Brazil. Repellents can stop mosquitoes bites, stop mosquito bites and remove the risk of infection. If you use registered mosquito repellents as directed on the label, they are effective and safe.

Common sense must prevail. Even if you’re concerned about the use of repellents, make some compromises while still protecting yourself for infection. Choose a lower dose DEET-based repellent and reply more often. This is a better approach than trying a repellent that hasn’t been proven effective.

I’m often asked what formulation works best. There are aerosol sprays, roll-ons, pump-pack sprays, creams, gels, lotions and even towelettes. There really haven’t been many scientific studies looking at which if these formulations work best, and for good reason. As the active ingredients in these formulations are the same, it doesn’t really matter. The critical issue is to choose a formulation that you’re most comfortable using to ensure you get a good coverage over exposed skin. I like creams and pump-pack sprays but I generally apply the product to my hands first and them spread across skin.

Always ensure you avoid getting repellent in your eyes or any cuts or abrasions.

I don’t like the smell or feel of mosquito repellents!

There is often a temptation for those who dislike DEET to use a “natural“, plant-based repellents. Notwithstanding that these products provide shorter periods of protection, tea-tree oil (particularly when used in home-made concoctions) also has the potential to cause skin irritation. While plant-based mosquito repellents may offer some protection against nuisance-biting mosquitoes, they shouldn’t be relied on to prevent mosquito bites in regions of mosquito-bore disease outbreaks.

Many health authorities recommend para-Menthane-3,8-diol (PMD), a product commonly known as “oil of lemon eucalyptus”. This is not an essential oil but rather the by product of the distillation process of Corymbia citriodora. The product does repel a range of biting insects and there is no evidence suggesting it should not be used in pregnancy. However, in Australia, this product is generally more difficult to find in grocery stores and pharmacies than DEET- or picaridin-based repellent formulations.

It would be brilliant if there was a non-topical options for stopping mosquito bites. Unfortunately, there is nothing that has been proven effective. Do not rely on mosquito repellent wrist bands as they do not provide adequate protection against mosquitoes. Also, remember that there is nothing you can eat or drink that will stop you being bitten by mosquitoes.

Rounding out the advice on mosquito repellents, make sure you pack some before you leave. You can never be sure of what products will be available at your destination or whether it has gone through the process of registration (e.g. APVMA in Australia or EPA-registered in the U.S.). It is not unheard of for mosquito repellent stock to sell out during outbreaks of disease.

Lastly, if you’re travelling to regions experiencing dengue, chikungunya and Zika virus outbreaks, don’t necessarily expect to be swarmed by mosquitoes in the same way you will around many of Australia’s coastal wetlands. Don’t be complacent if there are only a few about, remember, it only take one bite to transmit a pathogen. Don’t wait until you notice mosquitoes biting, wake up and put on that repellent.

There is a great set of questions with answers provided by the CDC for pregnant travellers on Zika risk and prevention and here is another reminder of the travel advice provided by the CDC and Australian Government for pregnant women.

If planning to travel while pregnant, consult your local doctor or travel health clinic for advice.

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.