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

Area of Science:

• Immunology
• Vaccinology
• Epidemiology

Background:

• Widespread mumps vaccination significantly reduced disease incidence.
• Increased mumps outbreaks since 2000 raise concerns about vaccine-induced immunity durability.
• Secondary vaccine failure due to waning immunity is a likely cause for breakthrough cases.

Purpose of the Study:

• To investigate the long-term durability of immune responses following two-dose measles, mumps, and rubella (MMR-II®) vaccination.
• To examine changes in measles- and mumps-specific antibody titers at approximately 7 and 17 years post-vaccination.

Main Methods:

• A cohort of 98 healthy adults received two doses of the MMR-II® vaccine.
• Immune markers for measles and mumps were assessed at two time points: ~7 and ~17 years after vaccination.
• Quantification of IgG and neutralizing antibody titers for both measles and mumps.

Main Results:

• Mumps-specific IgG titers showed a significant decline between the two time points.
• Mumps neutralizing antibody titers remained relatively stable, but were low at the later time point.
• Similar patterns were observed for measles-specific immune responses, with declining IgG and stable but low neutralizing antibodies.

Conclusions:

• Immune responses to mumps and measles vaccination may wane at different rates over time.
• Declining antibody titers suggest a potential for secondary vaccine failure, contributing to mumps outbreaks.
• Further research is needed to fully understand protective immunity against measles and mumps.