Mosquito Borne Diseases
Recent detections of Murray Valley encephalitis virus (MVEV) in Queensland, Kunjin virus activity in NSW, and Japanese encephalitis virus (JEV) in Victoria are an early signal of increased mosquito-borne virus activity ahead of the summer season.
With the arrival of summer, Queensland Health is urging people to protect themselves from mosquito bites. Mosquito abundance tends to increase in summer months, particularly following high rainfall, increasing risk of all mosquito-borne diseases
Be alert for signs and symptoms of mosquito borne diseases including Japanese Encephalitis, Murray Valley Encephalitis, Kunjin, Ross River, and Barmah Forest virus infection. Other mosquito-borne diseases should be considered if a patient has a history of recent overseas travel.
Clinicians should advise patients about risks of mosquito-borne viruses and promote mosquito bite avoidance measures. Healthcare professionals in Queensland are encouraged to maintain a high index of suspicion for mosquito-borne diseases and promote bite-prevention measures.
Incubation period
Usually 3–15 days (range 2-28 days), depending on the virus.
Symptoms
Most infections with JEV, MVE, and Kunjin virus are asymptomatic. When symptomatic, patients may present with:
- headache
- fever
- joint or muscle pain
- skin rash
- fatigue
- nausea
Signs of possible encephalitis (urgent assessment required):
- confusion or drowsiness
- neck stiffness
- seizures
- limb weakness
Transmission
Infection occurs through the bite of an infected mosquito. There is no person-to-person transmission.
Prevention
Encourage uptake of practical bite avoidance measures. Parents and carers should also ensure that children adhere to the same precautions wherever feasible. Recommended measures include:
- Avoid mosquito-prone areas during peak activity (particularly dawn and dusk).
- Wear long, loose-fitting, light-coloured clothing and covered footwear outdoors.
- Apply effective insect repellent containing DEET, picaridin, or oil of lemon eucalyptus. Reapply as necessary, according to manufacturer instructions.
- Use insecticide sprays, vaporising devices (indoors), or mosquito coils (outdoors, and in well-ventilated areas only).
- Ensure flyscreens are in good condition on fixtures in homes, tents or caravans.
- Reduce larval mosquito habitats by removing standing water, and emptying containers and rubbish that holds water.
Vaccination
Vaccines are available to prevent JEV disease. JEV vaccination is recommended and funded for certain at-risk groups including:
- Individuals who live, work or have a planned visit to identified local government areas (LGAs), Roma, or Hemmant (Brisbane), and who are at risk of mosquito bites
- Individuals who live near, work at, or plan to visit a piggery or pork abattoir or rendering plant.
- Individuals at risk through occupational or recreational activities that bring them in contact with mosquitoes or pigs.
- For detailed eligibility criteria and to locate JEV vaccine service providers in your area, visit Japanese encephalitis virus (JEV) immunisation centres | Queensland Health.
- Vaccine service providers registered with the Queensland Health Immunisation Program (QHIP) can order funded JEV vaccines using the Queensland Health Immunisation Order Forms.
Travel vaccination for JEV is also recommended, but not funded, for people travelling to Asia or Papua New Guinea.
Further information
Mosquito borne diseases | Queensland Health
The Australian Immunisation Handbook
Public health units | Queensland Health