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After 5 years of being diagnosed with rheumatoid arthritis, one every three patients will no longer be able to work.
Pubic lice (crabs) are usually spread through sexual contact. You cannot catch them by using a public toilet.
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.
Sperm cells are so tiny that 400 to 500 million (400,000,000–500,000,000) of them fit onto 1 tsp.
Normal urine is sterile. It contains fluids, salts, and waste products. It is free of bacteria, viruses, and fungi.
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