Abstract

Despite the availability of an effective vaccine since 1963 and past declarations of eradication, measles cases spiked worldwide in 2017, resulting in 110,000 deaths, with no signs of a downward trend in case numbers. Amid increasing vaccine hesitancy compounded by a lack of measles-specific antivirals, the potential for epidemics remains high, emphasizing the need for robust population immunity. Immunocompromised individuals are particularly at risk for deleterious sequelae, as public health guidelines suffer from vague guidance, often contraindicating live vaccine administration and making this population dependent upon herd immunity. This scoping review will identify the potential need for a measles booster vaccine dose in immunocompromised adults in the United States, by providing an overview of the literature regarding current indications and outcomes. EMBASE, Web of Science, and Ovid MEDLINE, were all searched using search terms specific to measles booster doses and the adult immunocompromised. In total, 2,335 articles were imported to Rayyan and after a two-tiered review, seven articles met the full inclusion criteria. Across immunocompromised populations including HIV, cancer, and IBD patients, community levels of measles immunity needed for herd immunity were consistently not met. Humoral immunity, if seronegative, can be safely reestablished using additional doses of the measles vaccine and in carefully selected patients, the vaccine was well tolerated when administered greater than 300 days post-transplant. Studies reviewed demonstrate the critical importance of a measles vaccine booster dose in this predominantly seronegative population, especially to reduce the outsized health burden the immunocompromised face. Further research is needed to clarify the guidelines to improve the generalizability of these findings, aiming for larger sample sizes with diverse patient populations.