Acute encephalitis (brain inflammation) caused by scrub typhus in Assam, India

In the state of Assam, many cases of acute encephalitis (brain inflammation) are caused by infection with the Japanese encephalitis virus which occurs each year. However, not all of the acute encephalitis cases thought to be due to Japanese encephalitis virus infection are actually confirmed by laboratory testing. A recent scientific study of 511 patients with acute encephalitis showed that about 20% had signs of recent infection with scrub typhus and not Japanese encephalitis.

Visit our Health Library for more information on exposure to and the prevention of Japanese encephalitis and Scrub Typhus.

Advice For Travellers

Travellers who develop the symptoms of acute encephalitis should insist on laboratory testing to confirm the cause of their infection.

The risk of exposure to scrub typhus for the general traveller depends on individual activities. Scrub typhus is transmitted by the bites of infected mite larva (an insect). During the wet season, these insects are usually found in tall grass and other vegetation. If diagnosed early, it can be successfully treated with readily available antibiotics. Travellers can reduce the risk of exposure to scrub typhus by taking all necessary precautions to avoid mite larva (insect) bites, especially if hiking or camping in rural areas. If symptoms develop after mite bites, seek medical care at once.