Consult with your local travel medicine authorities for travel medical advice and/or refer to World Health Organization or Centers for Disease Control and Prevention. You may require immunizations, depending on your travel destination, the length of your stay, and whether or not your routine immunizations are up-to-date. Since it can take several weeks for an immunization to protect you against a disease, you should consult a travel health clinic or your family physician 6 to 8 weeks before your trip in order to allow enough time for the vaccines or immunizing agent to take effect.
Health and Prevention
If you are traveling in endemic areas it is extremely important to avoid mosquito bites and to take tablets to prevent this disease. Symptoms range from fever, chills and sweating, headache, diarrhea and abdominal pains to a vague feeling of ill-health. Seek medical help immediately if malaria is suspected. Without treatment, malaria can rapidly become more serious and can be fatal.
If medical care is not available, malaria tablets can be used for treatment. You should seek medical advice, before you travel, on the right medication and dosage for you. If you do contract malaria, be sure to be re-tested for malaria once you return home as you can harbor malaria parasites in your body even if you are symptom free.
Travellers are advised to prevent mosquito bites at all times. The main messages are: wear light-coloured clothing; wear long trousers and long-sleeved shirts; use mosquito repellents containing the compound DEET on exposed areas (prolonged overuse of DEET may be harmful, especially to children, but its use is considered preferable to being bitten by disease-transmitting mosquitoes); avoid perfumes and aftershave; use a mosquito net impregnated with mosquito repellent (permethrin) – it may be worth taking your own, and impregnating clothes with permethrin effectively deters mosquitoes and other insects.
Also known as bilharzia, this disease is carried in freshwater by tiny worms that enter through the skin and attach themselves to the intestines or bladder. The first symptom may be tingling and sometimes a light rash around the area where the worm entered. Weeks later, a high fever may develop. A general unwell feeling may be the first symptom, or there may be no symptoms. Once the disease is established, abdominal pain and blood in the urine are other signs. The infection often causes no symptoms until the disease is well established (several months to years after exposure), and damage to internal organs is irreversible. Avoid swimming or bathing in freshwater where bilharzia is present. Even deep water can be infected. If you do get wet, dry off quickly and dry your clothes as well.
HIV (Human Immuno-deficiency Virus) develops into AIDS (Acquired Immune Deficiency Syndrome), which is a fatal disease. Any exposure to blood, blood products or body fluids may put the individual at risk. The disease is often transmitted through sexual contact or dirty needles – body piercing, acupuncture, tattooing and vaccinations can be potentially as dangerous as intravenous drug use. HIV and AIDS can also be spread via infected blood transfusions, but blood supplies in most reputable hospitals are now screened, so the risk from transfusions is low. If you do need an injection, ask to see the syringe unwrapped in front of you, or take a needle and syringe pack with you. Fear of HIV infection should not preclude treatment for any serious medical conditions. Most countries have organizations and services for HIV-positive folk and people with AIDS. For a list of organizations divided by country, plus descriptions of their services, see www.aidsmap.com.
Other diseases and Immunization
The actual immunizations you may require will vary according to your age, health, and any pre-existing medical conditions, as well as the nature of your travel, whether you will be staying in city hotels or travelling in remote rural areas. A travel health clinic or family physician should assess your individual circumstances and provide any vaccines that may be required for your trip. This is especially important if you plan to travel with infants or young children.
A list of diseases for which immunization may be required follows.
Diphtheria is an acute bacterial infection of the throat, nose and tonsils, resulting in lesions in the infected area. In severe cases, it can cause swelling and fluid build-up in the neck. Diphtheria can also infect the skin, causing lesions similar to impetigo. In Canada, a diphtheria booster shot is recommended every 10 years. All travellers should have up-to-date diphtheria shots prior to travel.
Hepatitis A is a viral disease affecting the liver. The symptoms include abrupt fever, malaise, loss of appetite, nausea and abdominal discomfort, followed by jaundice (yellowing of skin colour). Hepatitis A varies in severity and duration of the illness. In rare cases it can cause fatal liver damage. Protection against Hepatitis A through immunization with Hepatitis A vaccine is recommended for travellers to developing countries, especially rural areas, or areas where the hygienic quality of food and water supply is likely to be poor, or areas where Hepatitis A is widespread. For infants < 1 year and in individuals for whom the vaccine is contraindicated, Immune Serum Globulin (ISG) may be used. ISG provides protection for 4-6 months. Those living for prolonged periods in developing countries may require a booster. A travel health clinic or family physician will recommend which immunization is appropriate for individual circumstances.
Hepatitis B is also a viral disease affecting the liver. Usually more serious than Hepatitis A, its symptoms include gradual development of fever, loss of appetite, abdominal discomfort, nausea and vomiting, joint pain, rash and frequently progresses to jaundice. Its severity also varies, but a greater percentage of cases will involve destruction of the liver cells resulting in liver failure and death. Unlike Hepatitis A, Hepatitis B is transmitted through contact with infected blood and other body fluids. Any traveller who will be staying in an area with widespread Hepatitis B for longer than 6 months, or who is doing medical work, or who is likely to have contact with blood or sexual contact with residents of such areas, should be immunized with Hepatitis B vaccine.
Measles is an acute highly infectious disease caused by a virus. A fever usually develops before the symptoms which include inflammation of the tissue around the eyes, inflammation of the nasal tissues with severe runny nose, cough and red blotchy rash on the skin. Two doses of measles vaccine are recommended for all unimmunized travellers aged > 1 year who were born after 1970 and who are en route to a measles endemic area, unless there is serologic proof of immunity or physician documentation of prior measles.
Meningococcal meningitis is an acute bacterial infection resulting in the sudden development of fever, intense headache, nausea and often vomiting, stiff neck and a distinctive rash. Severe cases can result in delirium and coma and, if untreated, toxic shock and death. Meningococcal disease occurs seasonally in some regions of the world. In Sub-Sahara Africa, epidemics of meningococcal disease occur between December and June. Short-term travellers staying in city hotels with high standards, and little contact with the local population, are at minimal risk and should not need to be vaccinated for travel in Asia, Africa or Latin America.
Rabies is an acute viral infection, causing inflammation of the brain and spinal cord which is invariably fatal. Rabies occurs in many areas of the world. Travellers planning extended visits to countries where rabies control programs for domestic animals are inadequate, or who are planning to live in areas where rabies is widespread should consider pre-exposure immunization with rabies vaccine. A post-exposure vaccine exists for use following a bite by a rabid animal; however, it may not be easily available in all countries. Regardless of whether pre-exposure immunization has been given, any traveller bitten by a rabid animal should be given the post-exposure vaccine immediately.
Rubella, also known as German measles, is usually a mild illness caused by a virus. Its symptoms include fever, headache, malaise, inflammation of the tissues around the eyes and a widespread rash. Rubella can cause serious birth defects in an unborn child should the mother be infected during pregnancy. All children and women of childbearing age who have never had rubella or have not been previously vaccinated, should be given a rubella vaccine prior to travel.
Tetanus, also known as lockjaw, is caused by a toxin produced by the tetanus bacteria. This bacteria, found usually in the soil, infects an open wound or cut and begins to produce toxin. The toxin causes painful muscle contractions usually in the face and neck muscles. If untreated, the contractions can restrict breathing, causing death. In Canada, a tetanus booster shot is recommended every 10 years. All travellers should have up-to-date tetanus shots prior to travel.
Typhoid fever is caused by a bacterial infection. Its symptoms include a sustained fever, headache, malaise, loss of appetite, slowed heartbeat, enlarged spleen and rose spots developing on the trunk of the body. Typhoid is typically spread through water which has not been adequately treated to remove or kill the bacteria. Typhoid vaccine is recommended for any traveller who will have prolonged exposure to potentially contaminated water and food. Most urban tourist destinations provide water which is adequately treated; however, if you plan to travel in smaller cities and villages in developing countries, or rural areas off the usual tourist routes, you may need to be vaccinated against typhoid before you travel. A blood test is the most reliable test, but it will not show positive until a number of weeks after exposure.
You must produce proof of Yellow Fever immunization prior to entering most African countries. Yellow fever is transmitted through the bite of an infected mosquito. There is an effective vaccine against yellow fever, so if you have been immunized, you can basically rule this disease out. Symptoms of yellow fever range from a mild fever which resolves over a few days to more serious forms with fever, headache, muscle pains, abdominal pain and vomiting. This can progress to bleeding, shock and liver and kidney failure. The liver failure causes jaundice, or yellowing of your skin and the whites of your eyes – hence the name. There’s no specific treatment but you should seek medical help urgently if you think you have yellow fever.
International Health Regulations, established by the World Health Organization, require that travellers to regions where yellow fever is found be vaccinated against yellow fever and given an International Certificate of Vaccination. A valid certificate issued within the past 10 years is required for entry into 21 countries in Central Africa and South America. In addition, 102 other countries require proof of vaccination from travellers who have passed through (non-direct flights) an area where yellow fever occurs. Travellers without proper vaccination and certificate can be seriously delayed, depending on the route and destination. Both the vaccine and certificate are only available at certain travel medicine clinics recognized by the Public Health Agency of Canada as yellow fever clinics. http://www.phac-aspc.gc.ca/tmp-pmv/yf-fj/index-eng.php