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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.
Vaccines cause herd immunity. If the majority of people in a community have been vaccinated against a disease, an unvaccinated person is less likely to get the disease since others are less likely to become sick from it and spread the disease.
Adult head lice are gray, about ? inch long, and often have a tiny dot on their backs. A female can lay between 50 and 150 eggs within the several weeks that she is alive. They feed on human blood.
Though methadone is often used to treat dependency on other opioids, the drug itself can be abused. Crushing or snorting methadone can achieve the opiate "rush" desired by addicts. Improper use such as these can lead to a dangerous dependency on methadone. This drug now accounts for nearly one-third of opioid-related deaths.
Vaccines prevent between 2.5 and 4 million deaths every year.