Clinical Mumps Vaccine Efficacy

Abstract

From February 5 through April 23, 1982, 110 cases of mumps were reported among 357 students in a middle school in Ashtabula County, Ohio, an overall attack rate of 31%. Vaccine efficacy was calculated using a variety of case definitions, case surveillance systems, and vaccination-status ascertainment methods to evaluate their effects on the estimated vaccine efficacy. From data collected at the school for case ascertainment and vaccination status, clinical vaccine efficacy was initially estimated at 37%. By means of a uniform case definition (parotitis lasting two days or more) and only cases and vaccination status ascertained from parental questionnaires, estimated vaccine efficacy increased to 70%. From secondary attack rates in household members with provider-verified vaccination status, the vaccine efficacy further increased to 85%. This outbreak investigation confirms that the methods used to ascertain cases and determine vaccination status greatly affect estimates of vaccine efficacy. Studies relying solely on school records for case finding and determination of immunization status may provide misleadingly low estimates of vaccine efficacy for mumps vaccine as well as for other vaccines. Appropriate methods demonstrate that mumps vaccine is highly effective and support recommendations for its continued use.

Mumps resurgence in the United States

“…[8][9][10] However, field studies have documented lower estimates of vaccine efficacy, ranging from 75% to 95%. 11 Antibody levels induced by the vaccine are lower than antibody levels resulting from natural infection. 8,12,13 The duration of vaccine-induced immunity is unknown, but serologic and epidemiologic data collected during 30 years of live vaccine use indicate both the persistence of antibody and continuing protection against infection.…”

Estimation of vaccine efficacy and the vaccination threshold

“…Data from an outbreak of mumps in a middle school in Ashtabula County is used [17]. Among 335 children, 65 of them were vaccinated.…”

Vaccines and immunotherapies for the prevention of infectious diseases having cutaneous manifestations

“…[46][47][48] Outbreak-based studies, however, have reported lower efficacy rates, ranging from 75% to 95% protection from infection. [49][50][51][52] Although the duration of immunity in vaccine recipients is not completely known, serologic and epidemiologic evidence suggests that immunity persists for at least 30 years. [53][54][55][56] Adverse reactions generally are mild and uncommon after mumps vaccination.…”