Differential durability of immune responses to measles and mumps following MMR vaccination

Abstract

The development and wide-spread use of mumps vaccine resulted in a dramatic and sustained decrease in the incidence of mumps disease; however, since 2000, an increase in the size and number of mumps outbreaks in the United States and other countries has sparked renewed interest in the durability of mumps-specific immunity elicited by mumps vaccination. The most likely explanation for mumps cases in previously immunized persons may be secondary vaccine failure, or waning immunity. In the current study, we examined changes in markers of measles and mumps immunity at two timepoints, approximately 7 and 17 years after two-dose MMR-II® vaccination, in a cohort of 98 healthy adults. Our results indicate that mumps IgG titers exhibited a large and significant decline during this time period, while mumps neutralizing Ab titers were relatively stable. There was a similar discrepancy with measles-specific immune responses. For both pathogens, neutralizing antibody titers were fairly low and, given the length of time since vaccination, may have already declined. These data suggest that specific immune outcomes may wane at different rates and highlight our currently incomplete understanding of protective immune responses to mumps and measles.

Keywords: Antibodies; Cell-mediated immunity; Humoral immunity; MMR-II vaccine; Measles; Measles vaccine; Measles virus; Mumps; Mumps vaccine; Mumps virus; T cell ELISPOT.

Figure 1.. Measles and Mumps Serum IgG Titer and Neutralizing Ab Titer.

Virus-specific Ab titers (A and B) and neutralizing Ab titers (C and D) were measured as described in Methods. The box and whisker plots depict the median (solid line), interquartile range (boxes), and standard deviation (error bars), with the remaining data points plotted as open circles.

Figure 2.. Effect of Time Since Vaccination on Neutralizing Antibody Response.

A) Mumps-specific neutralizing Ab titers were plotted as a function of time since last vaccination. B) Measles-specific neutralizing Ab titers were plotted as a function of time since last vaccination. Each subject underwent two blood draws (denoted by the red and blue circles). A linear regression line (black) was superimposed over the data.

Figure 3.. Mumps Neutralizing Antibody Titers At Each Blood Draw.

A) Mumps Ab titer at the initial blood draw ~8 years-postvaccination. B) Mumps Ab titer at the second blood draw ~15 years post-vaccination. C) Difference in titer between blood draws.

Figure 4.. Measles Neutralizing Antibody Titers At Each Blood Draw.

A) Measles Ab titer at the initial blood draw ~8 years post-vaccination. B) Measles Ab titer at the second blood draw ~15 years post-vaccination. C) Difference in titer between blood draws.

Figure 5.. Sex Differences in Humoral Immune Response to Mumps and Measles.

A) Mumps neutralizing Ab titers in men and women. B) A) Measles neutralizing Ab titers in men and women.

Figure 6.. Correlation Between Mumps and Measles-Specific Immune Response.

A) Antibody titer correlation at first blood draw. B) Antibody titer correlation at second blood draw.

Figure 7.. Comparison Between Change in Ab Titer Between Pathogens.

The change in measles neutralizing Ab titer (Y-axis) is compared to the change in mumps neutralizing Ab titer (X-axis). Each data point represents a single subject.