Modes of Transmission
Food and Water
Contaminated food and water is one of the most common causes of illness among travelers, causing such diseases as: typhoid fever, hepatitis A, poliomyelitis, cholera, traveler’s diarrhea, and a variety of other diseases. Travelers’ diarrhea is the most common infectious illness to affect travelers. It can be caused by many different food and waterborne infectious agents.
Animals
Animals are a source of infectious disease. Minimize the risk of rabies and toxic reactions to poisonous bites (snakes, scorpions, spiders, etc.) by avoiding contact with local (wild and domestic) animals. Other infections from animals can be transmitted to humans through contaminated body fluids or feces, or by consumption of foods of animal origin, particularly meat and milk products. These disease risks include rabies, tularemia, brucellosis, leptospirosis and certain viral hemorrhagic fevers.
Insects
Travel to tropical climates entails contact with a variety of insects capable of transmitting infectious diseases. For example, the most well known culprit is the mosquito, which may transmit: yellow fever, malaria, Japanese encephalitis, dengue fever, and a variety of other diseases.
Contaminated Soil
Contaminated soil can enter cuts, deep wounds, and sores in the skin causing tetanus. Some parasites are capable of entering unbroken skin causing parasitic infections. Appropriate footwear will help minimize the risk. Certain intestinal parasitic infections, such as ascariasis and trichuriasis, are transmitted via soil. Infection may result from consumption of soil-contaminated vegetables. Fungal infections may be acquired by inhalation of contaminated soil.
Person to Person
Along with the common cold, many diseases can be transmitted from person to person and through blood transfusions, including measles, mumps, rubella, diphtheria, meningococcus, tuberculosis, influenza, hepatitis B, and AIDS, as well as chicken pox, pulmonary plague, hemorrhagic fever with pneumonia, pertussis, diphtheria, SARS, mumps and meningitis.
