RECENT wet conditions caused a localised invasion of mosquitoes.
Shoalhaven City Council environmental health unit manager Shane Pickering said swampy areas like Woollamia and Currambene Creek may be particularly bad for mosquitoes.
He said the mosquito increase has just occurred during this fortnight.
“Low lying areas will notice it being particularly bad,” he said.
“What we need now is a good cold snap to kill off those populations.”
Although other councils in tropical parts of Australia undergo aerial spraying to eradicate mosquito populations, the South Coast has never had such treatment.
Mr Pickering said eradication is technically something that is done in the tropics, where they have problems with diseases like malaria.
“We are governed by notifiable diseases with NSW Ministry of Health,” he said.
“If there was a certain outbreak of disease, obviously we would look into those preventative measures. But that has never happened in these areas.
“There are many species of mosquitoes and only some of the species are carriers of diseases like Ross River virus, Barmah Forest virus and malaria.”
Mr Pickering said council used to have extensive education programs to reduce mosquito plagues, but it has been so long since large numbers of mosquitoes had been present, they were abandoned.
“We used to encourage people to remove stagnant waters from around their homes and be aware of breeding grounds for mosquitoes,” he said.
“We are noticing an increase in mosquito populations due to the weather conditions. There are high incidents of mosquitoes because the high rainfall has left a lot of stagnant water behind which is perfect for breeding.
“I guess the message is to avoid the peak periods when mosquitoes are out, which is sunrise and sunset, or wear long trousers and long-sleeved shirts to protect yourself from bites.”
CSIRO scientist Jean-Bernard Duchemin researches mosquitoes and said compared with other years, this one was relatively dry and as a result larvae hatchings have been down.
“There are a lot of charted viruses in the north but Kunjin virus, also known as the west Nile virus could be spread in the south, given special weather/climate conditions,” Dr Duchemin said.
“There have not been findings of diseases in your region recently.”
Dr Duchemin said floods are other weather conditions which can cause an increase in breeding grounds for mosquitoes, combined with warm weather can cause a huge increase in populations.
“What we clearly saw in 2011 was a huge flood in Queensland and in that case, large bodies of water were left behind, increasing breeding grounds for local mosquitoes,” he said.