Legacy of vaccine hesitancy may be leaving workers vulnerable to measles infection and spread

One in five U.K. health care workers may not be fully immunized against measles, new research has found.

In a letter published in The Lancet, a team of immunology experts led by Professor Alex Richter at the University of Birmingham examined measles immunity in two groups of health care workers (HCWs).

The findings revealed that among a cohort of more than 400 HCWs, 13% of participants lacked measles antibodies, with a further 7.5% had borderline antibody status. Birth year was the major factor that determined immune status. Unusually for immunity, the younger the HCW the more likely they were to have a negative antibody result. This was confirmed in a second older HCW cohort from across the U.K.

The researchers suggest that the likely cause for this is that they were not vaccinated as there has been so few measles infections over the last 20 years until recently, and so they were unlikely to have acquired immunity through infection. Erroneous concerns about MMR vaccine safety that emerged in 1998 compromised vaccine uptake in those born after 1998.

Alex Richter, professor and honorary consultant in clinical immunology at the University of Birmingham and lead author of the letter, said, "Measles cases are currently at high levels across the country. Our new research highlights a concerning gap in measles immunity among health care workers, who may unwittingly be putting themselves and vulnerable populations at avoidable risk.

"Health care workers in patient-facing roles, especially those working with children and immune-compromised individuals, are at risk of contracting and spreading measles if they are not fully immune to measles."

Dr. Antonia Ho, clinical senior lecturer and consultant in infectious diseases at the MRC-University of Glasgow Center for Virus Research and first author, said, "Health care workers should check their vaccine history if they are uncertain and offered vaccination.

"Vaccination remains the most effective method of controlling measles. Therefore, every effort should be made to support health care workers, who are on the front lines of patient care, to ensure they are protected against measles to safeguard themselves and their patients."