12 Deadly Diseaes Cured in the 20th Century, 10-12

While small pox has been eradicated from the face of the earth, the war still wages against typhoid and yellow fevers in many parts of the world. Continue reading to find out how cures for these diseases are being administered.

10. Typhoid Fever

Typhoid is usually spread when food or water has been infected with Salmonella typhi, most often through contact with the feces of an infected person. Once the typhoid bacteria enter the bloodstream, the body mounts a defense that causes a high fever, headache, stomach pains, weakness, and decreased appetite.

Occasionally, people who have typhoid get a rash of flat red spots. Because sewage treatment in the United States is quite good, the disease is very rare, and the CDC reports only about 400 cases of it annually. However, people who live in developing countries where there is little water and sewage treatment, or where hand washing is not a common practice, are at high risk. Prime typhoid fever areas are in Africa, Asia, the Caribbean, India, and Central and South America.

WHO estimates 17 million cases occur globally with 600,000 deaths each year. Despite these daunting statistics, typhoid fever vaccination is available for people who travel to high-risk areas, and the disease can be effectively treated with antibiotics. Without treatment, the fever can continue for weeks or months, and the infection can lead to death.

11. Yellow Fever

Yellow fever is spread by mosquitoes infected with the yellow fever virus. Jaundice, or yellowing of the skin and eyes, is the hallmark of the infection and gives it its name. Most cases of yellow fever are mild and require only three or four days to recover, but severe cases can cause bleeding, heart problems, liver or kidney failure, brain dysfunction, or death.

People with the disease can ease their symptoms, but there is no specific treatment, so prevention via the yellow fever vaccine is key. The vaccine provides immunity from the disease for ten years or more and is generally safe for everyone older than nine months.

Yellow fever occurs only in Africa, South America, and some areas of the Caribbean, so only travelers who are destined for these regions need to be concerned about it. WHO estimates that there are 200,000 cases of yellow fever every year, and 30,000 of them are fatal. The elderly are at highest risk of developing the most severe symptoms. Although vaccination and mosquito-eradication efforts have made a great difference, WHO says yellow fever cases are on the rise again.

12. Smallpox

Unlike other diseases on this list, which can still appear in outbreaks when vaccination vigilance weakens, smallpox has been wiped off the face of the earth, except for samples of the virus held in labs in the United States and Russia for research purposes.

Symptoms of smallpox included a high fever, head and body aches, malaise, vomiting, and a rash of small red bumps that progressed into sores that could break open and spread the virus (the virus could also be spread via contact with shared items, clothing, and bedding). Smallpox was an entirely human disease -- it did not infect any other animal or insect on the planet. Thus, once vaccination eliminated the chances of the virus spreading among the human population, the disease disappeared; in fact, the United States has not vaccinated for smallpox since 1972.

Although smallpox was one of the most devastating illnesses in human history, killing more than 300 million people worldwide during the 20th century alone, scientists declared the world free of smallpox in 1979. The naturally occurring disease has been eradicated, but fears remain about the smallpox samples being used as bioweapons.

CONTRIBUTING WRITERS:

Helen Davies, Marjorie Dorfman, Mary Fons, Deborah Hawkins, Martin Hintz, Linnea Lundgren, David Priess, Julia Clark Robinson, Paul Seaburn, Heidi Stevens, and Steve Theunissen