2008-07-07 11:15:41 - As with all parts of the world, the South/Southeast asian region has its fair share of diseases, some which are equally common in the "Western" world, and others which may not be found in the "West".

Being a traveller would increase one's risk of contracting these diseases by the sheer presence of being in a new environment with the exact risk being determined by one's activities and geographical location. Of the differerent diseases that one can encounter, some are highly preventable, others are less preventable, and some are virtually unpreventable (thankfully, this does not include the

more serious diseases). The following are vaccine-preventable diseases found in the region for which we recommend immunization prior to travel.

Hepatitis A

This is caused by a virus that is transmitted to human beings through contaminated food. The virus infects the liver and causes fever, body aches and pains, liver inflammation, jaundice. Fortunately it does not tend to be a fatal disease, but can cause a significant amount of disability and disruption to one's trip as the average recovery time can last up to 3 weeks---and that is "bed-bound" recovery! Vaccination is recommended before travel and immunity is usually long-term---10 years and above.

Hepatitis B

This is also caused by a virus, and is transmitted through either sexual contact or contact with infected blood. Rates of Hep B are high in this region, particularly rates of "carriers". These are people who "carry" the virus, but have not symptoms, and hence can transmit it to other people unknowingly. Any type of sexual contact (with local population) and exposure to contaminated blood, needles, medical equipment can put one at risk for hepatitis b. Hepatitis B is more a more serious illness than hepatitis A. It can cause severe infection resulting in death, chronic liver inflammation eventually resulting in liver failure, or remain in the body for life as a "carrier state". A series of 3 injections can prevent the chances of contracting this disease. Immunity lasts for around 5 years.

Japanese Encephalitis

This is another viral disease. The virus originally lives in birds, but is spread from the birds to pigs through mosquitoes. In pigs, the virus amplifies and then spreads, via the mosquito, to human beings. This disease is fairly common in rural areas, along rice paddies, and farms. The virus causes a serious infection resulting in inflammation in the brain. Risk depends on duration of travel in rural areas and type of activities to be undertaken. Vaccination is only recommended if risk of contracting disease is significant enough. This should be discussed with your travel medicine provider prior to travel.

Rabies

This is a rabies-endemic region. The actual extent of the disease is unknown as no large scale research efforts have been undertaken. However, stray animals are prevalent and with no mass vaccination programs (for animals), the risk of contracting rabies is very real. Any bite, scratch, or saliva contact from dogs, monkeys, or stray animals can put one at risk. Rabies is a 100% fatal disease, so prevention is the only cure. Symptoms include fever and eventually severe neurological derangement including paralysis and death. A series of 3 shots prior to travel would offer some protection against rabies, however, if exposed, consult your travel medicine provider immediately for wound cleansing and booster vaccination shots.

Typhoid Fever

This is also very common, particularly in the Indian subcontinent. It is caused by a bacteria transmitted through food. Most of the locals would have some degree of natural immunity, but the traveller would be at significant risk. The disease can cause persistent fever, intestinal and liver inflammation. Untreated, the mortality is 10%. This can be reduced to under 0.1% if treated appropriately. In addition to common food safety precautions, vaccination is recommended. Vaccination comes in two forms: an injectible vaccine or an oral vaccine. Both forms would confer immunity for around 3 years.

As a general rule, it is advisable to visit your travel medicine doctor 4 to 6 weeks prior to your trip to discuss potential risks you may encounter, get the necessary vaccinations, prepare a travel kit including preventive and self-treatment medicines, and have a reliable contact point in the event that you fall ill.

For more information please see the Bangkok Hospital Travel Medicine Clinic