(Australian Associated Press)
It takes just one mosquito bite to pass on a nasty virus and Australians need to be vigilant about the annoying insects this summer, warns medical entomologist Dr Cameron Webb.
Especially if you are outside of metropolitan areas, he says.
“At the moment in Australia, particularly along the east coast, we are seeing a lot of activity of Ross River virus,” Dr Webb from the University of Sydney told AAP.
“So if you are near bushland where there is wetlands, mosquitoes and wildlife all about at the same time, that provides a prime opportunity for mosquito-borne disease.”
Ross River virus is a mosquito-borne disease that causes joint inflammation and pain, fatigue and muscle aches. Many infected people also develop a rash.
One of the best ways to protect against such illness is to use the appropriate insect repellent and apply it properly.
Dr Webb says current advice provided by health authorities does not reflect the range and variety of repellents available on supermarket shelves.
A recent review of topical mosquito repellents, published in journal Public Health Research & Practice, found there are almost 100 registered insect repellents available but only a handful contain effective active ingredients.
Dr Webb says it’s important that we are very specific about the active ingredients they contain and not simply talk about brands and formulations.
The most effective active ingredients are diethyltoluamide (DEET), picaridin or oil of lemon eucalyptus (p-menthane-3,8-diol,PMD) – these provide the longest-lasting protection.
Botanical extracts like tee-tree oil or lavender provide a much shorter period of protection.
“A DEET-based repellent that contains around 20 per cent DEET should provide around four hours protection but a tee-tree formulation that contains less than 10 per cent might only give you a couple of hours protection,” Dr Webb said.
This means you would have to reapply those botanical-based repellents two to three times as frequently.
The application is also critical to avoiding an annoying and potentially nasty mosquito bite.
“Being able to use an insect repellent correctly is really the best way to protect against mosquito bites,” Dr Webb.
Applying the repellent on all exposed areas of skin provides the best protection.
Also, anyone travelling to a region experiencing an outbreak of Zika or Dengue fever must use the repellent during the day.
“Because those mosquitoes that spread those viruses bite during the day, not in the afternoon or evenings as most Australians would be used to during the summer,” Dr Webb said.
Locally, its important holiday-makers pack repellent especially if they are going to be near bushland and wetland areas.