A recent outbreak of mosquito-borne Zika Virus in French Polynesia highlighted the vulnerability of small island communities. The virus is largely unknown outside Africa and parts of Asia, but took hold with great speed in islands such as Tahiti and New Caledonia.
French authorities saw this as something of a wake up call and funded the Institut Pasteur in Paris and Tahiti’s Institut Louis Malarde to find ways to increase the knowledge of disease threats across the Pacific, forewarn local communities and plan interventions as appropriate.
They in turn enlisted “locals” with specialist knowledge – including Prof Philip Weinstein from the University of South Australia (UniSA) and Dr Colleen Lau, a former colleague from the University of Queensland.
“Emerging diseases would not be a problem if traditional approaches could tackle them. We need new approaches, and that requires multidisciplinary input from collaborating experts like Prof Weinstein,” said the Director of the Unit of Emerging Infectious Diseases at the Institut Louis Malarde, Dr Didier Musso.
Prof Weinstein has worked extensively with mosquito-borne diseases, including Ross River Virus in Australia, Chikungunya in the Indian Ocean and rat-borne Leptospirosis in Samoa. He also was able to call in expertise from UniSA’s Mosquitoes and Public Health Research Group.
In the longer-term, however, it’s his broad skills and experience in what is known as “disease surveillance” that will underpin key parts of the Pacific-wide project.
New technology that can test blood using as little as a single drop on a small piece of filter paper makes large-scale testing of people across the vast expanses of the Pacific a reality.
Once French laboratories have extracted data from the samples, they will ask Prof Weinstein to explain what it means.
“The data will show what types of viruses are absent, and therefore at risk of becoming virgin soil epidemics, what types people might have had in the past but are not aware of, which is important to know because then there will be some degree of immunity in the population, and what types are epidemic, which is what has just happened with Zika Virus,” he said.
By matching the presence or potential of a virus with a given area’s ecology and human activities, it is possible to pinpoint specific risks by time and place and take steps – both specific and general – to avoid them.
“It’s a fusion of technology and community,” Prof Weinstein said.
It’s also quite complex, often involving GIS, layered maps, detailed information about animal numbers (both wanted and unwanted) and a sound knowledge of how the local community operates.
“There’s a strategic approach that’s generic – a certain set of tools that you have – but the tactics need to be tweaked to match the local ecology and that's the hard part,” he said. “The local ecology will differ and the intervention will differ depending on the local environment and the local population and which virus you are talking about.”
The first response is to let people know what sort of viruses are circulating and what they should be careful about. The next stage is to analyse potential scenarios that might lead to problems, and how to negate the risks.
“For example, if we know that when it rains a certain amount and the temperature is above a certain level for a number of days while animals have been moved into a certain area that the risk of a virus increases, then we can suggest that standing water be drained or that a certain insecticide be used at a certain time over a certain area,” Prof Weinsten said.
“It’s about identifying intervention points and the most cost-effective approach for people with limited resources.”
While resources may be limited, interest is not. Prof Weinstein said authorities and medical teams in many small Island nations were knowledgeable about what could and should be done and were keen to get the specific information they needed to take action.Jump to next article