Health Focus Archive
Travel Vaccinations
Travel vaccinations are immunizations that
are recommended, and sometimes required for traveling to certain parts of the
world. It is often important to discuss what is required with a physician prior
to traveling, especially with extensive international travel. To prevent the international
spread of disease (i.e., cholera, yellow fever, tuberculosis), many countries
will require certain vaccines in order to enter.
What diseases are transmitted by insects?
Many traveler's diseases are transmitted by insects
so it is important for travelers to take precaution to avoid insect bites. Yellow
fever, malaria, dengue fever, and plague are some of the more common diseases
spread by insects. The risk for exposure to such insects depends on the region
of the world. A vaccination is available for yellow fever and there are medications
available to help prevent malaria.
What diseases are transmitted
through food and water?
Cholera, typhoid fever, hepatitis A virus, and certain
parasitic infections are all transmitted through food and water. Avoid bad drinking
water as well as uncooked food, ill-prepared food, and street vendors whose food
preparation may not be sanitary. Beverages are safest when they have been boiled,
bottled, or filtered. Even ice may be contaminated.
How can I prevent traveler's diseases?
Meet with your physician at least 10 weeks prior to international
travel to allow for timely dosing of any necessary vaccinations as well as a discussion
of the risks of certain regions. Recommended vaccines in the include measles,
mumps, rubella, tetanus, diptheria, polio, and hepatitis. Other vaccines available
include influenza, meningococcal, yellow fever, Japanese Encephalitis, and typhoid.
Diseases and Vaccinations
Hepatitis A
An enterically transmitted disease that causes fever, anorexia, malaise, nausea, abdominal discomfort, followed within a few days by jaundice. Transmission may occur by direct person-to-person contact; or from contaminated water, ice, shellfish, fruits and vegetables or other uncooked foods contaminated when handling. Vaccine is recommended, but not required for all persons traveling to developing countries. Many cases have developed in travelers with "standard" tourist itineraries, accommodations and food consumption. The vaccine is offered as an injection with a booster given 6-18 months after first dose.
Side effects include pain and swelling at site of injection. Some people may experience headache, fatigue, fever or nausea.
Hepatitis B
A viral infection primarily transmitted through the exchange of blood or blood-derived fluids as well as through sexual activity. Symptoms include anorexia, abdominal pain, nausea and vomiting, often progressing to jaundice. 10% of cases will become chronic. The vaccine is recommended for health care workers, travelers anticipating direct contact with blood, or secretions, persons who are likely to seek medical, dental, or other treatment in local facilities during their stay or intimate sexual contact with potentially infected persons. An extended stay (> 6 months) in an area that is intermediately to highly epidemic with HBV warrants vaccination as well. The vaccine is offered as an injection in three series at 0,1, and 6 months.
Side effects are mild including soreness at injection site and rarely fever, nausea, aches and pains. A combined Hepatitis A & B vaccines is also available.
Typhoid
An acute febrile illness caused by the bacterium Salmonella typhi. Travelers contract the disease from contaminated food and water. Risk is greatest in Asia, Africa, Latin America and the Indian Subcontinent. Vaccine is not required; however, it is recommended for tourists traveling to smaller cities, villages, and rural areas off the usual tourist itineraries.
Side effects included headache, nausea, vomiting and tiredness. Not recommended for pregnant women or children less than 2 years of age. Allow about 2 weeks for vaccines to work.
Yellow Fever
A mosquito-borne viral disease causing flu-like symptoms and possibly hepatitis and hemorrhagic fever. The disease occurs only in parts of Africa and S. America. International regulations require proof of vaccination for travel to and from certain countries. Some countries recommend the vaccination for travel outside the urban areas of countries that do not officially report the disease. Some countries require and individual, who has been in countries that harbor the disease, to have a valid International Certificate of Vaccination. The vaccine is good for approximately ten years.
Cholera
This is not usually recommended for travellers due to its poor efficacy. But it will be useful for travellers in highly endemic areas who do not have ready access to medical attention. This is an injection giving 50% protection for 3-6 months. Side effects are common including inflammation around injection site and a mild flu-like illness.
Meningococcal Meningitis
An acute bacterial disease, characterized by sudden onset of fever, headache, nausea and often vomiting, stiff neck, and possibly a pink, macular rash. Vaccine is recommended for travelers going to sub-Saharan Africa, particularly in the Savannah areas extending from Mali eastward to Ethiopia (known as the "meningitis belt") especially during the dry season (December-June). The vaccine is offered as an injection and duration of immunity is thought to be at least 3 years. Advisories for travelers to other countries will be issued when epidemics of meningococcal disease are recognized that may be preventable by the vaccine. It is also required for pilgrims to holy places in Saudi Arabia.
Japanese Encephalitis
A common mosquito-borne viral encephalitis in Asia. Most cases are asymptomatic, but as many as 30% can be fatal. It is transmitted chiefly by mosquitoes in the Culex vishnui complex. Expatriates and travelers living for prolonged periods of time in rural areas where the disease is endemic are at greatest risk. Vaccination should be considered only for those who plan to live in endemic areas or for short-term travelers whose trips include visits to rural, farming areas (larvae are found in rice fields, marshes and stable collections of water around cultivated fields). The injected vaccine must be administered on days 0, 7, and 30 for a total of 3 injections. Full duration of protection is unknown. A booster may be recommended at 36 months.
Rabies
An acute, fatal viral encephalomyelitis causing paresis to paralysis, spasm of swallowing muscles, delirium and convulsions. It is usually transmitted by bites, but transmission has been confirmed by introduction of the virus into open cuts or mucous membranes. Travelers should be warned about the risk of acquiring rabies, especially in endemic countries such as S. America, Africa, Asia and Central America. Anyone who will be handling animals while traveling should strongly consider prophylaxis with the vaccination. Pre-exposure immunization consists of three injected doses--one each on days 0, 7, 21 or 28.
Tuberculosis
This is recommended only for children under the age of five who will be living in high prevalence area for a long period of time. It is also for health workers intending to work in high risk countries for a long period time. A skin test is needed before the vaccination. The vaccine BCG can only be given by a licensed centre like Travel Health Care. Prolonged inflammatory changes are common at the injection site.
POLIO BO
Poliomyelitis is an acute viral infection involving the gastrointestinal tract, and possibly the central nervous system. The majority of cases are asymptomatic, but flaccid paralysis of a single limb, quadriplegia, respiratory failure or even death may occur. An injected polio vaccine is recommended for travelers who have previously completed the primary course (at least 3 doses of live oral polio vaccine or inactivated polio vaccine) and who are traveling to polio-endemic areas. Transmission of polio continues to occur in Africa, Asia, the Middle East, and Eastern Europe. MUSC offers only the inactivated poliovirus vaccine (IPV), due to some cases of paralytic poliomyelitis occurring after vaccination with the live oral poliovirus vaccine (OPV).
TETANUS/DIPHTHERIA
Diphtheria and Tetanus remain serious health problems throughout much of the world. Most cases occur in unimmunized persons or in persons who are inadequately vaccinated. A booster dose of TD should be given at least every 10 years.
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