Using Locally Derived Sero prevalence Data on Measles Mumps Rubella and Varicella by Birth Cohort to Determine Risks for Vaccine-Preventable Diseases During International Travel.

Friday, 11th of December 2015

Using Locally Derived Sero prevalence Data on Measles Mumps Rubella and Varicella by Birth Cohort to Determine Risks for Vaccine-Preventable Diseases During International Travel.

Rosario-Rosario G Gareca M Kincaid H Knouse MC.

Author information

Abstract

BACKGROUND:

Measles mumps rubella and varicella (MMRV) were common childhood diseases in the United States prior to the introduction of their respective vaccines. Measles was declared eliminated in the United States in 2000. However 628 cases were reported in 2014 the majority of which have been linked to international travel. The study team set out to investigate the sero prevalence of MMRV in our local population to determine whether such a process can lead to meaningful recommendations for assessing travelers at risk.

METHODS:

We conducted a cross-sectional sero prevalence study using a quota sampling method. A total of 460 leftover serum samples were collected from individuals born prior to 1996 who live in the Lehigh Valley region of southeast Pennsylvania. The samples were allocated to five birth-year cohorts and the sero prevalence of each cohort to MMRV was compared. Additionally overall sero prevalence of each disease was compared with data from prior national studies. Gender differences within each birth cohort were also assessed.

RESULTS:

The overall sero prevalence values of measles mumps rubella and varicella were 85.8 82.8 96.6 and 97.4% respectively. There were significant associations between sero prevalence and birth cohort for measles (p = 0.01) as well as mumps (p = 0.037). The overall sero prevalence for our study sample was significantly different from the national sero prevalence results of measles mumps and rubella.

CONCLUSIONS:

Our study showed dramatically lower immunity rates for measles and mumps than those shown by prior national sero prevalence studies. The rates in many of the later birth cohorts born after 1966 were significantly lower than the rates reported as necessary to sustain herd immunity. Given that patients immunization records are not always available or complete collecting local sero prevalence data may be necessary to more accurately recommend antibody testing and vaccination during pre-travel assessments.