Experts say a state is about to enter a high-risk period for a mosquito-borne disease that causes fevers, muscle aches and rashes.
Residents in NSW have been urged to take extra caution following a spike in the number of cases of a mosquito-borne illness.
There were more cases of Ross River virus during 2020 than there have been in 30 years, mosquito expert and medical entomologist Associate Professor Cameron Webb said.
Associate Professor Webb told NCA NewsWire while everyone was distracted by COVID-19 last year, one of the biggest outbreaks of Ross River virus was quietly developing in the background.
“It was a really unusual summer because we started off very hot and dry. There were hardly any mosquitoes but in mid-February (2020) we had a huge amount of rain across NSW that provided the ideal conditions for mosquitoes,” he said.
“Mosquito numbers remained quite high well into Autumn and that was probably one of the major drivers of this increase in disease.”
More than 2000 people were infected with Ross River virus last year and NSW is fast approaching another high-risk period.
He said cases of the disease generally spike toward the end of summer and beginning of Autumn, meaning NSW residents should take extra caution.
“The reason for that is each summer the virus is circulating among wildlife before it gets to the mosquitoes,” Associate Professor Webb explained.
“And then we start to see transmission to people.
“Even though they might not be as common or abundant (now) as they were in the middle of the summer holidays, the risk is people become complacent and are less likely to use repellent and take those important steps to avoid mosquito bites.”
Mosquito numbers have boomed in certain parts of the state thanks to the La Nina weather event causing a more humid and wetter summer.
In October last year, the Bureau of Meteorology declared the La Nina event for the first time in a decade.
While the wet weather is welcomed by farmers and those who live in bushfire prone areas, mosquitoes love moisture too.
The pests are attracted to stagnant water, like ponds, lakes or puddles where they can lay their eggs.
“We’ve had a lot of rain in some areas where mosquito numbers have dramatically increased,” Associate Professor Webb said.
The main areas of concern are along the NSW coast, particularly in the far north.
“The risks are higher where you get people, wetlands and wildlife all together … and that tends to be concentrated on the coast,” he explained.
Mosquitoes can transmit a number of serious diseases including Barmah Forest.
While these diseases aren’t typically deadly, they can cause a range of worrying symptoms from fevers to muscle aches and rashes.
This problem isn’t restricted to regional areas either and there’s still a risk in the outskirts of Sydney.
Last month the South Eastern Sydney Local Health District issued a mosquito alert after high numbers of the pests were detected in Alfords Point in Sydney’s south.
NSW Health has since urged people to protect themselves against disease by wearing loose-fitting long sleeved shirts and long pants when outside and to apply mosquito repellent.
“Take special care during peak mosquito biting hours, especially around dawn and dusk, remove potential mosquito breeding sites from around the home and screen windows and doors,” NSW Health says on its website.
NSW Health has been contacted for comment on Ross River case numbers.