Residents and holidaymakers across New South Wales (NSW) are being urged to safeguard against mosquito bites this summer following new detections of the Japanese encephalitis (JE) virus and Murray Valley encephalitis (MVE) virus. Dr. Jeremy McAnulty, Executive Director of Health Protection at NSW Health, reported on the viral presence just as outdoor activities begin to ramp up.
"Mosquitoes thrive in warm conditions, increasing the risk of mosquito-borne illnesses such as Murray Valley encephalitis and Japanese encephalitis," Dr. McAnulty stated. He remarked the heightened risks are particularly concerning as both viruses were detected after recent surveillance programs. The JE virus has now been found in mosquito populations within the Moree area, marking the first positive findings for the program this year.
Dr. McAnulty noted the significance of the findings, saying, "Each year from November to April, NSW Health undertakes surveillance across the state, to provide important information about when mosquito-borne disease risk is elevated." His concerns mirrored increased awareness, especially as the hotter months approach.
The risk has become acute, with the JE virus also previously detected among feral pigs within Narromine Shire, and (most recently) the MVE virus found among local chicken flocks across Cowra and West Wyalong. Each of these detections brings to light the seriousness of mosquito-borne diseases which can cause severe brain swelling (encephalitis) and even death.
Disease symptoms can manifest as neck stiffness, disorientation, and, at worst, seizures or coma—seriously affecting those infected. Notably, Dr. McAnulty highlighted, "These detections indicate the risk for mosquito-borne virus transmission is widespread, particularly in the 55 NSW local government areas at higher risk of JE within the inland regions." The affected localities include Moree, Narrabri, Gwydir, and others within New England.
Officials emphasized the importance of preventive measures. For individuals residing or spending time frequently within higher-risk regions, the JE vaccine is available through local General Practitioners (GPs) and health services, albeit there is currently no vaccination available for MVE. Dr. McAnulty encouraged, "Anyone planning to be outdoors should take action against mosquito bites."
Preventative actions are as follows: applying repellent containing DEET or picaridin, wearing light and loose clothing, and avoiding outdoor activities during dawn and dusk. Many recommendations also include ensuring home environments are secure from mosquito breeding sites, such as disposing of old tires and flowerpots.
Despite these rising concerns, there have been no reported human cases of JEV acquired within NSW since October 2022. Nonetheless, the potential impact of these mosquito-borne viruses should not be underestimated, as historical statistics reveal about 30% of those who develop acute JE may not survive; for about half of those who do, long-term neurological effects may persist.
Health officials remain vigilant, monitoring mosquito levels and viral presence through their statewide surveillance efforts. For individuals interested, information on eligibility for receiving the JE vaccine, including free offerings, can be located on the NSW Health website.
NSW Health would also like to remind residents during this summer period to stay informed about symptoms and treatment options for these serious viruses. There's currently no specified treatment for acute JE, emphasizing the importance of prevention. The recommended preventive measures highlight how residents can secure their safety during peak seasons of mosquito activity.
The public's cooperation is key, and as warmer weather draws closer, health officials are urging everyone to remain alert and proactive about mosquito bites, ensuring measures are taken to enjoy outdoor activities without the looming threat of these diseases. With their commitment to public health, the messages shared by Dr. McAnulty and his team resonate with the urgency of caution as recreational outdoor activities become more appealing.