Wednesday September 3, 2008

Travel protection

THE DOCTOR SAYS
By DR MILTON LUM

For safe travels, make sure you vaccinate yourself.

MORE and more people are travelling abroad for business and holidays these days. However, spending long duration in foreign lands and visiting remote destinations can expose travellers to infections diseases and unhygienic environments. Some countries have specific vaccination requirements before a traveller is permitted to enter.

Vaccination is the administration of a vaccine to stimulate an immune response in a recipient (vaccinee) that will prevent disease if he comes into contact with the corresponding infectious organism. If successful, vaccination results in immunisation – the vaccinee becomes immune to the disease. The terms “vaccination” and “immunisation” are often used interchangeably.

Vaccination is effective in preventing certain infectious diseases. They are generally safe and serious adverse reactions are uncommon. Vaccination provides travellers the possibility of avoiding a number of dangerous diseases that they may be exposed to abroad.

However, vaccines do not provide protection for all recipients. No traveller should assume that there is no risk of getting the diseases that he has been vaccinated against.

Additional precautionary measures advised by the doctor should be taken. It is also essential to remember that immunisation cannot be a substitute for avoiding potentially contaminated food and water.

Which vaccines are needed?

It would be prudent for travellers to find out about the risk of diseases in the countries they intend to visit and the necessary steps to prevent diseases. Possible sources of information include their regular doctor and reliable internet websites such as that of the World Health Organisation (www.who.int).

The risks depend on the local prevalence of the diseases and individual factors that include:

Age, sex and general health: Some individuals are at increased risk of infection while others cannot be given certain vaccines because they have particular medical conditions.

Immunisation status: It is important to ensure that the routine vaccinations have all been given, such as poliomyelitis and tetanus, including the booster doses.

Travel itinerary and duration of travel: This includes the countries, region and where one would be staying. The risk is higher in rural areas than in urban areas.

Time of travel: Some diseases are more common at certain times of the year, such as influenza in winter.

Depending on the traveller’s individual risk, the doctor will advise on the need for vaccinations, preventive medication (prophylaxis) and precautionary measures.

There is no single vaccination schedule for all travellers. The doctor will also advise on the precautionary measures that can be taken to avoid disease(s). There are three categories of vaccines available for travellers:

Routine vaccination: Tuberculosis (BCG), diphtheria, tetanus and pertussis (DPT), hepatitis B, poliomyelitis, measles, mumps and rubella (MMR), type B haemophilus influenzae , pneumococcal disease, chicken pox, rotavirus, human papilloma virus (HPV) and influenza.

Selective use for travellers: Hepatitis A, meningococcal disease, typhoid fever, cholera, yellow fever, Japanese encephalitis, rabies and tick-borne encephalitis.

Mandatory vaccination: Yellow fever, meningococcal disease and polio.

Yellow fever is prevalent in sub-Saharan Africa and South America. Mandatory yellow fever vaccination is carried out for two different reasons: to protect the individual in areas where there is a risk of exposure to yellow fever infection and to protect countries from the importation of yellow fever.

Saudi Arabia requires mandatory vaccination against meningococcal disease for pilgrims doing the Haj and visits to Medina. Some polio-free countries, for instance Saudi Arabia, may require travellers from polio-endemic countries to be vaccinated against polio.

When to vaccinate

Many vaccines need time for the body to develop an immune response that provides adequate protection. This varies with the vaccine, the number of doses required and whether there has been previous vaccination against the same disease. That is why it is advisable to consult a doctor two to three months prior to departure in order to allow enough time for the vaccination schedules to be completed. If this is not possible and departure is imminent, it is still advisable to consult the doctor for advice and possibly some vaccinations.

It would be wise for women who are pregnant, may be pregnant or breast feeding to discuss with their doctors prior to any vaccination. It is not advisable for people with certain medical conditions to be vaccinated, for instance those who are immuno-compromised, taking medicines that affect the body’s immune system or undergoing chemotherapy or radiotherapy. The doctor will be able to provide the necessary advice.

Some recipients may experience side effects from the travel vaccinations given. In many instances, they are mild and transient, and do not require treatment. Some individuals develop an allergic reaction to the vaccines which may require treatment. That is why it is important for the vaccination to be completed at least a fortnight prior to departure.

Vaccination provides travellers with the possibility of avoiding a number of dangerous diseases that they may be exposed to when travelling. Which vaccine and when to vaccinate are matters that can addressed by consulting your doctor.

nn Dr Milton Lum is the chairperson of the Commonwealth Medical Trust. This article is not intended to replace, dictate or define evaluation by a qualified doctor. The views expressed do not represent that of any organisation the writer is associated with.