There has been a lot of media attention around Japanese Encephalitis (JE) in Bali over the last week. On further inspection we stand by our usual recommendations for Bali, which has not changed over many years. That is, mosquito avoidance is very important when visiting anywhere in the tropics. This includes during the day as well as dusk, dawn and overnight. Personal insect repellent should contain DEET (30%) or Picaridin and should be applied to exposed skin. Wear long sleeved loose clothing and consider soaking clothes in Permethrin in advance of travel. These simple measure will help protect you against a number of different illnesses including Dengue, Chikungunya and Zika all of which are more likely than JE.
What we do know about JE in Bali is that the vaccine was added to the local childhood immunisation schedule earlier this year for the first time and this was based on background surveillance of the illness. Children were vaccinated because they are known to be at higher risk of developing neurological complications of JE.
While JE exists across Indonesia, it was found to be more common in Bali. The illness is transmitted by a type of mosquito which lives in rural or semi-rural areas in Asia and is more common in the wet season, which for Bali is November to April. As we have stated previously the risks remain low for short stay, urban travel to Bali when mosquito avoidance measures are followed.
Vaccination against Japanese Encephalitis is possible but not necessarily recommended for everyone. Date of departure and length of stay are taken into account for example as the vaccines take a little while to become effective. However those of you who travel to Bali for short but frequent trips, may be at increased risk due to accumulative exposure. For specific advice in relation to your circumstance and trip, you need to make an appointment to see one of our travel doctors so they can work out what’s best for you.
Dr David Rutherford