Travel to Developing Countries - Infectious Diseases

Nonvector-Borne Bacterial or Viral Infectious Diseases Encountered by Travelers

Disease

Countries of Infection

Severity and Symptoms

Treatment and Prevention

Cholera

Bacterial infection transmitted in contaminated water or food.

Outbreaks occur in many developing countries with poor sanitation. More common in warm months.

Perfuse, watery diarrhea, abdominal pain, and vomiting lasting 1 - 3 days. In severe cases, profound dehydration can be fatal.

Treatment: Tetracycline and oral hydration salts usually effective within 48 hours. Consume as much purified water as possible.

Prevention: Risk to travelers is considered low, and the vaccines are not produced in the U.S. or required for international travel.

Typhoid Fever and Parathyroid Fever(Enteric Fever)

Bacterial infection (salmonella typhi) in contaminated water or food. Can be spread by flies.

Can occur in any region where food or water is contaminated. Outbreaks common after natural disasters in poor countries. Tends to occur in urban areas.

Initial flu-like symptoms and low-grade fever that increases every day for a week or more. In the second stage, fever stabilizes at 103 - 104 °F. "Pea soup" diarrhea or constipation can develop. Untreated, disease can last up to 4 weeks and is fatal in 10% of patients. After symptoms end, the patient is still infectious.

Treatment: Antibiotics essential. Ciprofloxacin is antibiotic of choice. Fluid replacement and nutrition maintenance is critical. Even when symptoms have resolved, patients may be contagious until bacteria is eliminated.

Prevention: Vaccinations recommended for travelers visiting high-risk countries for more than four weeks. Drink bottled water. Take same precautions as for traveler's diarrhea.

Hepatitis A

Viral infection transmitted in contaminated water or food.

Worldwide. Highest risk in developing nations, particularly where sanitation is poor and cholera and typhoid are prevalent.

Nausea and vomiting, decreased appetite, itching, extreme fatigue, jaundice, fever, and abdominal pain. Serious complications are rare, but recovery may take 6 - 9 months.

Treatment: No specific treatment for acute hepatitis. Abstain from alcohol and sexual contact. Avoid dehydration. Keep own eating and cooking utensils separate from others.

Prevention: Wash hands after using the bathroom. Two vaccines are available as well as combination vaccine for hepatitis A and B. Vaccination recommended for travel to any nation where risk is intermediate or high. Immunity from vaccine may develop more slowly in elderly people. CDC recommends vaccination 4 weeks before travel. HepA vaccine is recommended for all children at age 1.

Hepatitis B

Viral infection transmitted through contaminated blood, or through sex or sharing needles with an infected person. Can be passed from cuts, scrapes, and other breaks in the skin.

Common in Southeast Asia, Africa, the Middle East, islands of the South and Western Pacific, the Amazon region of South America, and the Mediterranean.

Flu-like mild symptoms. Sometimes rash, aching in joints. Symptoms usually appear 4 - 24 weeks after exposure but can occur long after initial infection. Often no symptoms, but even patients with symptoms can remain chronically infected with the virus. Chronic infection can lead to cirrhosis, liver failure, and liver cancer.

Treatment: Treatment of symptoms.

Prevention: Several vaccines are now available, including a combination vaccine (Twinrix) for hepatitis A and B. Vaccination recommended for all children and for travelers to developing countries.

Poliomyelitis (Polio)

Viral infection transmitted in contaminated water or food.

Most developing countries in Africa, and parts of Asia.

Symptoms in small children can be mild and flu-like. More likely to be serious in older children and adults. Symptoms include severe fever, headache, stiff neck and back, deep muscle pain. Can lead to paralysis and can be fatal.

Treatment: Treatments only for symptoms.

Prevention: Universal immunization required. All babies should receive vaccination as part of standard vaccine schedule, with booster at 4 -6 years of age. Booster needed for adults traveling to developing country. Inactivated polio vaccine (IPV) is used.

Meningococcal Disease

Bacterial infection in the fluid and membranes covering the brain and spinal cord. Spread through coughs, sneezes.

The so-called meningitis belt (countries extending across sub-Sahara Africa from Nigeria to Somalia).

Fever, chills, headache, stiff neck, rash caused by bleeding into the skin, and vomiting. Can also cause pneumonia and loss of limbs. Particularly dangerous for children.

Treatment: Early administration of antibiotics is essential.

Prevention: Vaccines (including boosters for previously vaccinated individuals) for travelers in the meningitis belt and other areas with outbreaks. Vaccine now recommended as standard for all children 11 - 12 years of age and entering college freshmen living in dorms and not previously vaccinated.

Leptospirosis

Exposure to bacteria from the urine of animals by swimming or bathing in contaminated fresh water.

Tropical and subtropical countries pose highest risk.

High fever, severe headache, diarrhea, and eye inflammation. In severe cases, can develop internal bleeding and liver and kidney damage.

Treatment: Antibiotics (as early as possible).

Prevention: Avoid water activities where leptospirosis occurs.

Severe Acute Respiratory Syndrome (SARS)

Respiratory infection caused by coronavirus. Spread by infected droplets from coughing, sneezing.

First identified in China in 2003, not currently active in any other parts of the world.

Serious form of unusual pneumonia, resulting in acute respiratory distress. Hallmark symptoms are high fever, cough, difficulty breathing, or other respiratory symptoms.

Treatment: Supportive care.

Prevention: Practice good hygiene, avoid contact with SARS patients.

Tuberculosis

Bacterial infection spread through air by coughing or sneezing. Also has been passed in unpasteurized milk.

High rates found in Africa, Asia, Central and Eastern Europe (including former Soviet Union), Latin America.

Coughing, weight loss, fever, night sweats. Can spread from lungs to central nervous system, genitourinary system, bones and joints. Ninety percent of infected people have no symptoms.

Treatment: Multiple drugs for 6 months or longer.

Prevention: BCG vaccine available for children in developing countries. Not routinely used for travelers. Consider screening children who return from developing countries. Isoniazid or other medications can prevent acute disease in people who are infected but not ill.

Rabies

Virus transmitted from exposure to saliva from an infected animal (even from licking). Dogs are main carriers but all mammals susceptible.

Worldwide except Antarctica (some specific countries are rabies free).

Disease is nearly always fatal once symptoms develop.

Treatment: Immunoglobulins after bites, vaccine if not previously vaccinated (previously vaccinated travelers require booster vaccine, but not immunoglobulins). Clean the wound with soap and water, and iodine if possible, immediately after bite. If symptoms develop, supportive treatments only.

Prevention: Vaccine is available and recommended for travelers who intend to work with animals or are likely to come in contact with animals in countries where the rabies virus is common. Immunization does not eliminate the need for treatment after exposure to the virus.