Pregnant women and measles: we need to be vigilant during outbreaks

A number of countries including the UK are currently experiencing large outbreaks of measles affecting mainly young children but also adolescents and young adults. Women of childbearing age are a particular group of concern because the 1988 Wakefield Lancet paper, which falsely asserted a connection between the MMR vaccine and autism, was associated with a large and sharp decline in childhood MMR uptake over several years. This has left large cohorts of non-immune adolescents and young adults (born between 1998 and 2004), including young women who are now of childbearing age and remain susceptible to measles as well as rubella. Pregnant mothers are at higher risk of serious complications, such as pneumonia, with adverse pregnancy complications including fetal loss, premature birth, and neonatal death. Measles infection may also result in subacute sclerosing panencephalitis (SSPE), a very rare but very severe and invariably fatal neurodegenerative complication that typically manifests many years after acute measles infection but can have a short-onset latency with a fulminant course in pregnant women. Here, we summarise the epidemiology of measles infection, factors associated with the current measles outbreaks, as well as the risks and outcomes of measles, including SSPE, in pregnancy. We propose an algorithm for clinical management of measles infection in pregnancy. We also highlight the importance of early liaison with local health protection teams for risk assessment, diagnosis and management of suspected measles in pregnancy and close contacts as well as susceptible pregnant women exposed to a person with measles in the community.