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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.
When Gabriel Fahrenheit invented the first mercury thermometer, he called "zero degrees" the lowest temperature he was able to attain with a mixture of ice and salt. For the upper point of his scale, he used 96°, which he measured as normal human body temperature (we know it to be 98.6° today because of more accurate thermometers).
Pregnant women usually experience a heightened sense of smell beginning late in the first trimester. Some experts call this the body's way of protecting a pregnant woman from foods that are unsafe for the fetus.
Multiple sclerosis is a condition wherein the body's nervous system is weakened by an autoimmune reaction that attacks the myelin sheaths of neurons.
Normal urine is sterile. It contains fluids, salts, and waste products. It is free of bacteria, viruses, and fungi.