Sources: CountryWatch, Inc., Disease Control Center and the World Health Organization. Own elaboration.
Always consult your doctor or competent health authority.
Only the yellow fever vaccine is mandatory if you come from some countries of Central/South America and sub-Saharan Africa. Detailed countries here Link. There is no risk of yellow fever in Southeast Asia.
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Vaccines to consider (as appropriate for age):
All travellers. The measles vaccine, in addition to the routine vaccines. Make sure that you are up-to-date.
Typhoid Fever
Most travellers. The bacterium Salmonella Typhi causes serious illness and is transmitted by contaminated food and water.
It is present in areas of Southeast Asia, however, the risk to travellers is lower if they implement the necessary hygienic measures with the water and food.
You can also prevent the infectious with a vaccine, oral or injectable. It’s recommended if your itinerary includes endemic areas.
Hepatitis A
Most travellers. In short, it is an infectious disease caused by the hepatitis A virus (HAV) that affects the liver. It is transmitted by water, contaminated food and direct contact with stools of infected people.
It is present in Southeast Asia.
The disease can be prevented with a vaccine.
Vaccination is recommended for travellers going to endemic areas or places with insufficient hygienic-sanitary conditions.
Cholera
For some travellers. The bacterium Vibrio Cholerae causes severe intestinal disease and is transmitted by contaminated water and food.
There are endemic areas in Southeast Asia, however, the risk for travellers is low if they implement the necessary hygienic measures.
Hepatitis B
For some travellers. It is an infectious disease transmitted by the hepatitis virus (VHB), also affecting the liver.
It is transmitted mainly via sexual, blood transfusions with contaminated blood or contaminated material (syringes, tattoos) and vertical mother-child.
Hepatitis B is endemic in many countries including Southeast Asia.
The vaccine is recommended for travellers living long stays, more than 6 months.
Taking into account the vias of transmission, travellers have to take extreme precautions in situations of risk.
Malaria
For some travellers. A parasite spread by the bite of a mosquito is the cause of this serious disease in humans.
Most infected people show the symptoms from 10 days to 4 weeks after infection. They experience high fever, sweating, headache, chills, yellowing of the eyes and skin and tremors, among others.
These parasites live in the blood, so they cannot be transmitted from person to person.
To prevent malaria you can protect yourself against mosquito bites: long-sleeve, light-coloured shirts and pants, bed nets, insect repellent and through medicine. In this last case, you will have to take the medicine some time before the trip, during the journey and also a few weeks after returning home. Ask your doctor.
Japanese Encephalitis
For some travellers. This is a virus spread by mosquitoes that can cause serious neurologic disease, even being fatal.
Most infections result mild, only fever and headache, even without signs. But roughly 0.4% of those infected get seriously sick. The incubation period is 4 days to two weeks.
There is no cure for the Japanese Encephalitis, so the treatment tries to help the sick person fight the infection and relieve serious clinical symptoms.
The vaccine against this virus is safe and effective.
To prevent this disease you can also protect yourself against mosquito bites: long-sleeve, light-coloured shirts and pants, bed nets and insect repellent.
Rabies
For some travellers. It is an acute viral disease that affects the central nervous system and is transmitted by direct contact (biting or secretions) with animals like dogs, cats, monkeys, etc.
The travellers must take into account a specific assessment depending on the personal risk, a vaccine can be made before or after exposure (after contact with a suspect animal).
Meningococcal meningitis
It is an acute bacterial infectious disease of worldwide distribution observed that affects the brain membrane.
It is transmitted through direct contact with infected people through droplets of respiratory or throat secretions.
Vaccination is recommended for travellers older than 2 years who will visit endemic areas of meningitis A or C during the dry season (November to May) and who will live risk situations.
Poliomyelitis
Poliomyelitis is a highly infectious viral disease that still stays in some less developed countries, affecting mainly the nervous system of young children.
Vaccination is recommended for travellers who go to high endemic areas, who will be in close contact with the population.
Tetanus
It is a disease caused by the bacterium Clostridium tetani, which enters the body through wounds or erosions on the skin or mucous membranes.
It is essential to clean any wound as soon as possible and disinfect it.
Vaccination is recommended to everyone, especially travellers.
Other vaccines
There are other vaccines that are only recommended in special situations, so it is necessary to evaluate each case individually.