See also epdemiology.
Most severe influenza outbreak of the 20th century. It apparently started as a fairly mild strain in a U.S. army camp in early March 1918. Troops sent to fight in World War I spread the virus to western Europe. Outbreaks occurred in nearly every inhabited part of the world, spreading from ports to cities along transportation routes. Pneumonia often developed quickly and killed within two days. Among the most deadly epidemics in history, it left an estimated 25 million dead; unusually, half the deaths were among 20- to 40-year-olds.
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Acute contagious viral disease with inflammatory swelling of the salivary glands. Epidemics often occur, mostly among 5- to 15-year-olds. Cold symptoms with low fever are followed by swelling and stiffening in front of the ear, often on both sides. This rapidly spreads toward the neck and under the jaw. Pain is seldom severe, with little redness, but chewing and swallowing are difficult. During recovery in patients past puberty, other glands may be affected, but usually not seriously. The testes may atrophy, but sterility is very rare. While inflammation of the brain and meninges is fairly common, chances of recovery are good. Mumps needs no special treatment, and patients usually develop immunity. Vaccination can prevent it.
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EVOLVING TO FIGHT EPIDEMICS: WEAKNESS CAN BE AN ADVANTAGE LESS RESISTANCE CAN SOMETIMES BE BETTER THAN MORE--AT LEAST IN A FRESHWATER LAKE.
Mar 31, 2012; ARLINGTON, VA -- The following information was released by the National Science Foundation: When battling a deadly parasite...