| 1 | Major infectious diseases |
| 2 | This entry lists major infectious diseases likely to be encountered in countries where the risk of such diseases is assessed to be very high as compared to the United States. |
| 3 | These infectious diseases represent risks to US government personnel traveling to the specified country for a period of less than three years. |
| 4 | The degree of risk is assessed by considering the foreign nature of these infectious diseases, their severity, and the probability of being affected by the diseases present. |
| 5 | The diseases listed do not necessarily represent the total disease burden experienced by the local population. |
| 6 | The risk to an individual traveler varies considerably by the specific location, visit duration, type of activities, type of accommodations, time of year, and other factors. |
| 7 | Consultation with a travel medicine physician is needed to evaluate individual risk and recommend appropriate preventive measures such as vaccines. |
| 8 | Diseases are organized into the following six exposure categories shown in italics and listed in typical descending order of risk. |
| 9 | Note: The sequence of exposure categories listed in individual country entries may vary according to local conditions. |
| 10 | food or waterborne diseases acquired through eating or drinking on the local economy: |
| 11 | Hepatitis A - viral disease that interferes with the functioning of the liver; spread through consumption of food or water contaminated with fecal matter, principally in areas of poor sanitation; |
| 12 | victims exhibit fever, jaundice, and diarrhea; |
| 13 | 15 <percnt> of victims will experience prolonged symptoms over 6 - 9 months; |
| 14 | vaccine available. |
| 15 | Hepatitis E - water - borne viral disease that interferes with the functioning of the liver; most commonly spread through fecal contamination of drinking water; |
| 16 | victims exhibit jaundice, fatigue, abdominal pain, and dark colored urine. |
| 17 | Typhoid fever - bacterial disease spread through contact with food or water contaminated by fecal matter or sewage; |
| 18 | victims exhibit sustained high fevers; |
| 19 | left untreated, mortality rates can reach 20 <percnt>. |
| 20 | vectorborne diseases acquired through the bite of an infected arthropod: |
| 21 | Malaria - caused by single-cell parasitic protozoa Plasmodium; transmitted to humans via the bite of the female Anopheles mosquito; |
| 22 | parasites multiply in the liver attacking red blood cells resulting in cycles of fever, chills, and sweats accompanied by anemia; |
| 23 | death due to damage to vital organs and interruption of blood supply to the brain; |
| 24 | endemic in 100, mostly tropical, countries with 90 <percnt> of cases and the majority of 1.5 - 2.5 million estimated annual deaths occurring in sub-Saharan Africa. |
| 25 | Dengue fever - mosquito - borne (Aedes aegypti) viral disease associated with urban environments; manifests as sudden onset of fever and severe headache; occasionally produces shock and hemorrhage leading to death in 5 <percnt> of cases. |
| 26 | Yellow fever - mosquito - borne viral disease; |
| 27 | severity ranges from influenza-like symptoms to severe hepatitis and hemorrhagic fever; |
| 28 | occurs only in tropical South America and sub-Saharan Africa, where most cases are reported; |
| 29 | fatality rate is less than 20 <percnt>. |
| 30 | Japanese Encephalitis - mosquito - borne (Culex tritaeniorhynchus) viral disease associated with rural areas in Asia; |
| 31 | acute encephalitis can progress to paralysis, coma, and death; |
| 32 | fatality rates 30 <percnt>. |
| 33 | African Trypanosomiasis - caused by the parasitic protozoa Trypanosoma; transmitted to humans via the bite of bloodsucking Tsetse flies; |
| 34 | infection leads to malaise and irregular fevers and, in advanced cases when the parasites invade the central nervous system, coma and death; |
| 35 | endemic in 36 countries of sub-Saharan Africa; |
| 36 | cattle and wild animals act as reservoir hosts for the parasites. |
| 37 | Cutaneous Leishmaniasis - caused by the parasitic protozoa leishmania; transmitted to humans via the bite of sandflies; results in skin lesions that may become chronic; endemic in 88 countries; |
| 38 | 90 <percnt> of cases occur in Iran, Afghanistan, Syria, Saudi Arabia, Brazil, and Peru; |
| 39 | wild and domesticated animals as well as humans can act as reservoirs of infection. |
| 40 | Plague - bacterial disease transmitted by fleas normally associated with rats; |
| 41 | person-to-person airborne transmission also possible; |
| 42 | recent plague epidemics occurred in areas of Asia, Africa, and South America associated with rural areas or small towns and villages; |
| 43 | manifests as fever, headache, and painfully swollen lymph nodes; |
| 44 | disease progresses rapidly and without antibiotic treatment leads to pneumonic form with a death rate in excess of 50 <percnt>. |
| 45 | Crimean-Congo hemorrhagic fever - tick - borne viral disease; |
| 46 | infection may also result from exposure to infected animal blood or tissue; |
| 47 | geographic distribution includes Africa, Asia, the Middle East, and Eastern Europe; |
| 48 | sudden onset of fever, headache, and muscle aches followed by hemorrhaging in the bowels, urine, nose, and gums; |
| 49 | mortality rate is approximately 30 <percnt>. |
| 50 | Rift Valley fever - viral disease affecting domesticated animals and humans; |
| 51 | transmission is by mosquito and other biting insects; |
| 52 | infection may also occur through handling of infected meat or contact with blood; |
| 53 | geographic distribution includes eastern and southern Africa where cattle and sheep are raised; |
| 54 | symptoms are generally mild with fever and some liver abnormalities, but the disease may progress to hemorrhagic fever, encephalitis, or ocular disease; |
| 55 | fatality rates are low at about 1 <percnt> of cases. |
| 56 | Chikungunya - mosquito - borne (Aedes aegypti) viral disease associated with urban environments, similar to Dengue Fever; characterized by sudden onset of fever, rash, and severe joint pain usually lasting 3 - 7 days, some cases result in persistent arthritis. |
| 57 | water contact diseases acquired through swimming or wading in freshwater lakes, streams, and rivers: |
| 58 | Leptospirosis - bacterial disease that affects animals and humans; |
| 59 | infection occurs through contact with water, food, or soil contaminated by animal urine; |
| 60 | symptoms include high fever, severe headache, vomiting, jaundice, and diarrhea; |
| 61 | untreated, the disease can result in kidney damage, liver failure, meningitis, or respiratory distress; |
| 62 | fatality rates are low but left untreated recovery can take months. |
| 63 | Schistosomiasis - caused by parasitic trematode flatworm Schistosoma; |
| 64 | fresh water snails act as intermediate host and release larval form of parasite that penetrates the skin of people exposed to contaminated water; |
| 65 | worms mature and reproduce in the blood vessels, liver, kidneys, and intestines releasing eggs, which become trapped in tissues triggering an immune response; |
| 66 | may manifest as either urinary or intestinal disease resulting in decreased work or learning capacity; |
| 67 | mortality, while generally low, may occur in advanced cases usually due to bladder cancer; |
| 68 | endemic in 74 developing countries with 80 <percnt> of infected people living in sub-Saharan Africa; |
| 69 | humans act as the reservoir for this parasite. |
| 70 | aerosolized dust or soil contact disease acquired through inhalation of aerosols contaminated with rodent urine: |
| 71 | Lassa fever - viral disease carried by rats of the genus Mastomys; endemic in portions of West Africa; |
| 72 | infection occurs through direct contact with or consumption of food contaminated by rodent urine or fecal matter containing virus particles; |
| 73 | fatality rate can reach 50 <percnt> in epidemic outbreaks. |
| 74 | respiratory disease acquired through close contact with an infectious person: |
| 75 | Meningococcal meningitis - bacterial disease causing an inflammation of the lining of the brain and spinal cord; |
| 76 | one of the most important bacterial pathogens is Neisseria meningitidis because of its potential to cause epidemics; |
| 77 | symptoms include stiff neck, high fever, headaches, and vomiting; |
| 78 | bacteria are transmitted from person to person by respiratory droplets and facilitated by close and prolonged contact resulting from crowded living conditions, often with a seasonal distribution; |
| 79 | death occurs in 5 - 15 <percnt> of cases, typically within 24 - 48 hours of onset of symptoms; |
| 80 | highest burden of meningococcal disease occurs in the hyperendemic region of sub-Saharan Africa known as the “Meningitis Belt” which stretches from Senegal east to Ethiopia. |
| 81 | animal contact disease acquired through direct contact with local animals: |
| 82 | Rabies - viral disease of mammals usually transmitted through the bite of an infected animal, most commonly dogs; |
| 83 | virus affects the central nervous system causing brain alteration and death; |
| 84 | symptoms initially are non-specific fever and headache progressing to neurological symptoms; |
| 85 | death occurs within days of the onset of symptoms. |