Respiratory syncytial virus vaccines

Although safety concerns had excluded pregnant women from clinical research, demands for their inclusion in clinical vaccine development increased following the disproportionate effect of COVID-19, Ebola and Lassa fever outbreaks on pregnant women and/or their fetuses (Salloum et al, 2023). A search of 400 phase 3 and 4 vaccine clinical trials in healthy populations registered between 2018 and 2023 found that of 22 studies (6%) either designed for pregnant women or with them included as part of a larger population, three were maternal vaccines aiming at protecting the fetus from respiratory syncytial virus (Salloum et al, 2023).

According to the NHS (2024), respiratory syncytial virus is a common cause of bronchiolitis in babies, some of whom may need hospital treatment. Respiratory syncytial virus may also cause pneumonia in babies and older adults and the vaccine is recommended if you are pregnant (from 28 weeks) or if aged 75–79 years, since ‘the vaccine helps reduce the risk of [respiratory syncytial virus] causing serious problems such as pneumonia and bronchiolitis’. In terms of cost-effectiveness, Hodgson et al (2024) noted that ‘for infants under six months old in England and Wales, a year-round [maternal vaccine] programme with 60% coverage would avert 32% … of [respiratory syncytial virus] hospital admissions’.