The number of mosquito-borne diseases has skyrocketed in northern NSW.
In a year of more rain and high temperatures, health experts believe prevention will be key to keeping these diseases at bay.
So far in 2020, 427 cases of Ross River Virus have been reported in the Northern NSW Local Health District. Most of these cases were reported in the fall.
That number excludes cases reported after December 7, and is a five-fold increase from the 77 cases recorded in 2019.
In 2015, the total number of Ross River virus cases was 463, the highest in the last 20 years.
Notifications of Ross River Virus in residents of the local health district of northern NSW by month of disease outbreak. January 2017 to December 2020.
NSW health data for Barmah Forest virus shows 267 cases recorded in northern NSW prior to December 7th. In 2019, 62 patients were reported.
Between 2000 and 2015, the Northern NSW Local Health District typically recorded more than 200 cases of Barmah Forest virus per year. In the past five years, however, the numbers have rarely risen above 100 cases a year.
The key is the amount and number of mosquitoes present in the area, according to medical entomologist Assoc / Prof Cameron Webb of NSW Health Pathology.
Mosquito cells infected with the green fluorescent Ross River virus
Mr. Webb is an academic at the University of Sydney and also works as a medical entomologist for NSW Health.
“Mosquitoes are a big public health problem,” he said.
“The region (the northern rivers) may have more than 100 species of mosquitoes, but there are few that cause serious health problems or play a role in the spread of the virus.
“In northern NSW, for example, in the case of the Ross River virus, there are a number of mosquitoes in the area that can spread the virus between native animals and humans and respond to different environmental conditions.”
There are no other serious mosquito-borne diseases like zika, dengue or malaria in Australia, Webb said.
“But the people who suffer from the diseases we have here, while not fatal, can have serious consequences,” he said.
The medical entomologist released a document this week entitled Reflections on an Extremely Unusual Summer: Bush Fires, COVID-19, and Mosquito-borne Diseases in NSW, Australia.