Thread: Japanese Encephalitis

Japanese encephalitis (JE) is a serious infection of the brain caused by a virus that can be spread by some (but not all) types of mosquitoes.

JE occurs in many parts of Asia, and has recently occurred in Papua New Guinea. It has also occurred in north Queensland. Since 1995, four people in the Torres Strait and one person in Cape York have had JE. The type of mosquitoes that are able to spread JE breed extensively early in the wet season, and it is possible that the prevailing northwest winds and tropical storms may have blown infected mosquitoes into the Torres Strait.
Symptoms


The vast majority of people infected with JE virus have no symptoms, while a small proportion may have very severe symptoms such as headache, high fever, convulsions and coma. Of these severe cases, approximately one third die and one third are left with permanent disabilities.
Transmission

The JE virus can only be spread by the bite of an infected mosquito. Mosquitoes become infected soon after they bite infected pigs.

After a person is bitten by an infected mosquito, it usually takes five to 15 days for the first symptoms to appear.
Treatment


There is no specific treatment. Treatment usually involves management of the symptoms.
Prevention


While travelling in Asia and Papua New Guinea, particularly during the monsoonal wet season, avoid exposure to mosquitoes during hours of biting (eg. dusk until dawn) and use repellents. In particular:

• Wear loose-fitting light-coloured clothing with long sleeves, long trousers and socks especially at dusk and in the first few hours after sunset.
• Use insect repellent containing diethyltoluamide (DEET) or picaridin when outdoors. Lotions and gels are more effective and longer lasting than sprays.
• Use mosquito-proof tents when camping.
• Use mosquito nets when sleeping unless accommodation is air conditioned or has mosquito screens on doors and windows.

There is also a vaccine for protection against JE. The current JE vaccine requires two injections, given 28 days apart; it is currently only available for people 18 years or older. The vaccine can be given in pregnancy, if necessary.

Headaches and muscle aches are the most common side effects following JE vaccination, occurring in up to 20% of people. They usually occur within the first three days after vaccination, are usually mild, and disappear within a few days.

The JE vaccine is recommended for:

• Some travellers to Asia and Papua New Guinea depending on where they are going, for how long and at what time of year.
• All adult residents of certain outer islands in the Torres Strait.

Help and Assistance


For further information please contact your local doctor, community health centre or nearest public health unit.
References

Australian Government Department of Health and Ageing. 2008. The Australian Immunisation Handbook, 9th edition. Canberra: Australian Government.

MIMS Online. Accessed 02/03/10.
Mandell GL, Bennett JE and Dolin R. Principles and practice of infectious diseases, 7th edition. Philadelphia (PA). Churchill Livingstone Elsevier; 2010: p.2133-56 (vol 2).
Related Content

• Barmah Forest virus fact sheet
• Kunjin virus disease fact sheet
• Ross River virus fact sheet

Last Updated: 22nd February, 2011
Date Valid to: 7th April, 2011

I have found your health warnings and advice cool man! Thanks for sharing this.

A further thought..... also recommended for those visiting the top end.......JE vaccination is recommended for:

• all residents (>1 year of age) of the outer islands in the Torres Strait, and
• all non-residents who will be living or working on the outer islands of the Torres Strait for a cumulative total of 30 days or more during the wet season (December to May).

NB. The period of greatest risk is from February to March and the vaccination course should be completed before February. Those arriving in the outer islands late in the wet season (ie. in May) have arrived after the risk period and do not require vaccination. Those visiting the outer islands in the dry season (June to November) do not require vaccination. Those visiting only the inner islands,
including Thursday Island, do not require vaccination.

Your post makes for interesting reading and cheers for the contribution. SWAG

.Tropical disease of any kind is a worry when livving in the tropics !,Skin lesions and tropical ulcers are another problem that we need to be made aware of.Often people don't have the information on what causes them and how to look after them when they go to live in these places....

value your contribution mate cheers!

I think you still get a booklet in your passport maybe it should contain a booklet of diseases[ how to avoid recognise and treat] found in the country you are visiting or may be given one as you clear customs ? Or does something similar already happen?