September 26, 2024

Modelling study looking at whether protection from the MMR vaccine wanes over time

The vast majority of cases of measles in England are in unvaccinated children and young people and outbreaks are always driven by low vaccine coverage, but the proportion of measles cases in adults who had received two doses of the MMR vaccine as children has increased in recent years (seen in a dataset that began in 2010).

A team of scientists from the London School of Hygiene & Tropical Medicine has carried out a retrospective modelling study to explore which scenario best explains recent cases of measles in double-vaccinated people during measles outbreaks.  (The study does not do any forecasting of future scenarios.)  The study is being published in the Lancet Public Health.

The authors compared different scenarios (including no waning of the vaccine, and waning beginning at different time points after vaccination) to see which scenario best fitted cases observed in recent years.

There are some limitations to the model, including that modelled scenarios cannot fully reflect the detail and complexities of reality e.g. geographical differences, and that the vaccination and case data put into the model themselves have limitations.

Journalists came along to this press briefing to hear from the authors of the study and to ask their questions.

Speakers included: 

Dr Alexis Robert, Research Fellow in Infectious Disease Dynamics, London School of Hygiene & Tropical Medicine

Dr Anne Suffel, Research Fellow in Vaccine Epidemiology, London School of Hygiene & Tropical Medicine

Prof Adam Kucharski, Professor of Infectious Disease Epidemiology, London School of Hygiene & Tropical Medicine

This Briefing was accompanied by an SMC Roundup of comments.