Travel to Developing Countries - Infectious Diseases

Less Common Vector-Borne Diseases

Disease and Method of Transmission

Countries of Infection

Severity and Symptoms

Treatment and Prevention

African sleeping sickness (African Trypanosomiasis)

Parasite transmitted by tsetse fly bite.

Rural Africa, between latitudes 15 degrees N and 20 degrees S.

Symptoms may include fever, chills, headache, fluid accumulation in hands and feet, sleepiness, lethargy, and convulsions. Without treatment, the sickness is fatal.

Treatment: Pentamidine and suramin for early stages. Rimantadine under investigation. Melarsoprol and eflornithine for second stage. Nifurtimox in combination with eflomithine is a new combination (as of 2009) approved by the World Health Organization as a second line treatment.

Prevention: Flies are attracted to dark, contrasting colors. Flies are not affected by insect repellents.

Chagas' disease (American Trypanosomiasis)

Parasite transmitted by infected Reduviid bugs.

South and Central America

In the acute stage, symptoms can include a skin lesion, fever, loss of appetite, lymph node swelling, spleen and liver enlargement, and inflammation of the walls of the heart. Symptoms that may occur years or decades later include dementia, weakening of the heart, dilation of digestive tract, weight loss.

Treatment: Benznidazole and nifurtimox are usually only effective in acute attacks. Benzimidazole is also used for recurrences. Antiparasitic treatment may be recommended.

Prevention: Avoid buildings made of mud, adobe, and thatch, which can harbor the reduviid bug.

Dengue

Virus transmitted by mosquitoes.

Can occur in any tropical or subtropical country. Greater risk in cities than in the country. Present in over 100 countries world-wide, putting some 2.5 billion people at risk.

High fever, severe headache, vomiting, backache, eye pain, muscle and joint pain, occasionally rash on trunk and upper arms. Disease ends abruptly after 2 - 7 days. Patients usually recover, but internal bleeding and fatal hemorrhage can occur. This stage of the disease is called dengue hemorrhagic fever.

Treatment: Blood transfusions, fluids, pain killers. (Aspirin, ibuprofen, or other NSAIDs should not be used, but acetaminophen is okay.)

Prevention: No vaccine has been developed. Prevention requires protection against mosquito bites, particularly at dawn and dusk.

Encephalitis

A number of different viruses carried by mosquitoes.

Worldwide risk although higher in some regions than others. High-risk areas include China and Korea, India, Southeast Asia.

Can be mild to life threatening. Brain swelling produces symptoms that include headache, neck stiffness, confusion, irritability, fever, weakness, dizziness, tremors, seizures, and paralysis. Serious symptoms include lethargy, delirium, coma, and even death.

Treatment: Symptomatic treatment only.

Prevention: The vaccine for Japanese encephalitis (Je-Vax) is recommended only if travelers are visiting rural areas in high-risk Asian countries for more than 30 days.

Leishmaniasis

Parasitic disease transmitted by a sand fly.

Found in 88 countries around the world.

Most common forms cause skin sores and mouth and nose ulcers, sometimes disfiguring. Organ infection can involve spleen, liver, and bone marrow.

Treatment: Antimony-containing drugs (meglumine antimonate, Glucantime; sodium stibogluconate, Pentostam) for organ infection; also pentamide isethionate (Pentam 300), amphotericin B (Fungizole). Fluconazole is also effective for skin sores.

Prevention: No vaccine available.

Plague

Bacteria carried by rodents and transmitted by fleas.

Most plagues are transmitted by handling infected animals. However, the Indian pneumonic plague is airborne. Human plague reported in recent years in Africa, South East Asia, parts of South American and the US. Recently been reported in India, Vietnam and Zambia. Risk generally in rural mountainous areas.

Swollen and tender lymph nodes, fever, chills, headache, malaise, prostration, and gastrointestinal symptoms. Can be fatal without treatment.

Treatment: Antibiotics, particularly streptomycin. Alternatives include gentamicin, tetracyclines, chloramphenicol.

Prevention: Use insect repellents and avoid handling any animals. Adults traveling to countries with plague outbreak may consider preventive antibiotics. Children may take sulfonamides.

Schistosomiasis

Schistosoma parasitic worms live off a specific snail in fresh water contaminated with feces.

Lake swimming in sub-Saharan Africa is a particular hazard for schistosomiasis in travelers. Other countries: Brazil, Puerto Rico, St. Lucia, Egypt, Southern China, the Philippines, and Southeast Asia.

Within days, itchy skin or rash. Within 1 - 2 months, fever chills, cough, muscle aches.

Can be mild, but also can damage liver, kidneys bladder, intestines, or central nervous system.

Treatment: Praziquantel (Biltricide) or oxamniquine (Vansil). Reports of resistance have raised concern.

Prevention: Do not swim or wade in fresh water in countries where schistosomiasis occurs. Boil drinking water for 1 minute. Heat bath water to 150 °F for 5 minutes.