Every year the U.S. Department of Agriculture distributes millions of oral rabies vaccines in eastern states to dose raccoons. In rural parts of these states, the vaccines are dropped from an aircraft.

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How Is a Vaccine Approved for Use?

Vaccines play an essential role in disease prevention, helping minimize the spread of contagious illness and saving countless lives. Before vaccines ever gain widespread use in humans, however, they undergo years of research and development, with multiple rounds of clinical testing, to ensure that