Perspectives on the relative resurgence of mumps in the United States
S. L. Cochi, S. R. Preblud and W. A. Orenstein
Division of Immunization, Centers for Disease Control, Atlanta, GA 30333.
Although the United States has enjoyed great success in the control of
mumps since the licensure of live virus mumps vaccine in 1967, a relative
resurgence of mumps during the 1986-1987 period has raised concerns about
the long-term effectiveness of mumps vaccine. We received mumps
surveillance data, historical information on mumps vaccine distribution and
recommendations for its use, survey data on levels of mumps immunization in
US children during the 1973-1985 period, the effect of mumps immunization
school laws on the reported incidence of mumps among states with and
without such laws, and studies of mumps vaccine effectiveness. Following
licensure, a decade elapsed before mumps vaccine was endorsed as a routine
immunization of childhood, while immunization survey and vaccine
distribution data reflected only gradual acceptance of the vaccine.
However, mumps incidence declined during this period, resulting in a
relatively underimmunized cohort of children born between 1967 and 1977 who
grew up during a period when the risk of exposure to mumps was rapidly
declining. The resurgence of mumps since 1986 has been characterized by a
selective increase in incidence and a shift in the age group at highest
risk to middle and high school students in those states lacking
comprehensive mumps immunization school laws. Postlicensure field
evaluations of mumps vaccine effectiveness have not demonstrated waning
vaccine-induced immunity. The data indicate that the relative resurgence of
mumps in the United States is chiefly due to a failure to vaccinate all
susceptible persons, especially those who are now between 10 and 19 years
old. Mumps immunization school laws offer an approach to deal with the
problem of continuing susceptibility in school-age populations.
