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Autoimmune diseases occur when the immune system destroys its own healthy tissues. When this occurs, white blood cells cannot distinguish between pathogens and normal cells.
Malaria was not eliminated in the United States until 1951. The term eliminated means that no new cases arise in a country for 3 years.
Asthma attacks and symptoms usually get started by specific triggers (such as viruses, allergies, gases, and air particles). You should talk to your doctor about these triggers and find ways to avoid or get rid of them.
The first-known contraceptive was crocodile dung, used in Egypt in 2000 BC. Condoms were also reportedly used, made of animal bladders or intestines.
Since 1988, the CDC has reported a 99% reduction in bacterial meningitis caused by Haemophilus influenzae, due to the introduction of the vaccine against it.