As of 11 May 2022, the Australian Department of Health has reported 41 cases, including four deaths, of Japanese encephalitis virus (JEV) across four states, these being New South Wales, Queensland, South Australia and Victoria. People in these areas are advised to avoid mosquito bites at all times.
JEV is a mosquito-borne virus which affects the central nervous system and is most common around areas of rice and pig farming. JEV is transmitted from animals, mainly pigs and birds, to humans through the bite of an infected Culex mosquito which feeds in the hours around dusk. No human-to-human transmission occurs.
Advice for travellers
All travellers to endemic countries or outbreak areas are potentially at risk of infection, with the risk increasing for those who:
- travel to rural areas during transmission seasons
- participate in outdoor activities during twilight hours
- travel for a prolonged period of time
All travellers should be advised on:
- the risks and potentially severe consequences of JEV
- practicing strict mosquito bite avoidance, including the correct use of insect repellents
- minimising outdoor activities during twilight hours when Culex mosquitoes bite
Travellers at an increased risk of developing severe clinical disease are those:
- with pre-existing chronic medical conditions
- younger than 10 years of age
- older than 50 years of age
For most travellers, the risk of acquiring infection will be very small, but vaccination should be considered by those:
- frequently exposed to bites in rural infected areas, such as backpackers, agricultural workers and volunteers
- at ongoing risk or repeatedly visiting high risk areas, such as flood plains, rice paddies, marshlands and pig farms
- staying for short periods during outbreaks
- staying for more than one month in infected areas
- going to live in an endemic area
Further information on JEV can be found on the TRAVAX (for health professionals) and fitfortravel (for the general public) websites.
Sources: TRAVAX, 12 May 2022 and fitfortravel, 12 May 2022