Related Conditions

Altitude sickness

Altitude sickness occurs when you cannot get enough oxygen from the air at high altitudes. This causes symptoms such as a headache and not feeling...


Diphtheria is an acute bacterial disease that can infect the body in the tonsils, nose, or throat and/or the skin. While this was a common childhood disease in the 1930s, a vaccine against diphtheria has now made it very rare in the U.S. and other developing countries.

Japanese encephalitis

There are seventeen spieces of birds that are the known carriers of and transmit West Nile Encephalitis (WNE) to humans via the Culex, Aedes and...


A parasite causes malaria; a bite from an infected Anopheles mosquito passes the parasite to humans. After the parasites enter the body by a mosquito bite, they disappear from the circulating blood within an hour and gather in the liver. After several days, infected red blood cells (RBCs) emerge from the liver and infect other RBCs.


Measles, also known as rubeola, is a very contagious viral illness. It has a distinct rash and a fever. It is usually spread through direct contact with droplets from coughs or sneezes from a person with measles.

Meningococcal disease

Meningococcemia is a rare infectious disease characterized by upper respiratory tract infection, fever, skin rash and lesions, eye and ear...


Measles, mumps and rubella are serious diseases caused by viruses. They are spread from person to person through the air. Measles virus can...

Motion sickness

If you've ever been sick to your stomach on a rocking boat or a bumpy airplane ride, you know the discomfort of motion sickness. Although it...


Poliomyelitis, most often called polio, is spread by a virus and can cause paralysis. The disease is now rare in the U.S. because of a vaccine against the virus. However, polio still exists in a few countries.


Tetanus is a sometimes fatal disease of the central nervous system, caused by a poison (toxin) made by the tetanus bacterium which usually enters the body through an open wound. Tetanus bacteria live in soil, manure, the human intestine and other places.

Yellow Fever

Yellow fever is a rare viral disease caused by the bite of a mosquito. Symptoms may include fever; flu-like symptoms, such as headache, vomiting and backache; bleeding of the gums; bloody urine; and yellowing of the skin or eyes (jaundice).


Pneumonia is an infection of one or both of the lungs caused by bacteria, viruses, or fungi. It is a serious infection in which the air sacs fill with pus and other liquid.