Since the U.S. mumps vaccine program started in 1967, there has been a more than 99 percent decrease in the nation’s reported mumps cases. “Mumps is no longer common in the United States, but sporadic outbreaks still occur, even in highly vaccinated populations,” Rubin says. “Mumps was historically a disease of childhood, but outbreaks now typically involve young adults, particularly in high density, close contact environments such as on college and university campuses.”
Today in the United States, children get two doses of a combination vaccine that contains a mumps component. “But our research indicates that by college age, levels of anti-mumps virus antibodies had declined substantially,” Rubin adds, which might leave people unprotected.
So, in collaboration with the Centers for Disease Control and Prevention (CDC), Rubin and his team studied college-age participants’ response to a third vaccine dose. Participants responded with a sharp increase in antibodies within the first month after vaccination, but levels went down to nearly pre-dose levels within one year.
Conclusion? Vaccines only provided a limited immune response for a couple years. Every dose of vaccine after the first one works for less time than the previous one.
The third dose of a typical vaccine only provides protective immunity for ONE YEAR, and then the person is open to getting that infection again.