BACKGROUND AND AIMS: 7- and 13-valent pneumococcal conjugate vaccines (PCV) have been an effective part of routine immunization using a 2+1 schedule in the United Kingdom (UK) for the previous 11 years. Studies are ongoing to evaluate effects of removing a dose from the primary series. Our objective is to estimate health and economic impact of reducing from a 2+1 to a 1+1 PCV13 schedule.
METHODS: A dynamic transmission model was developed using UK serotype-specific invasive pneumococcal disease (IPD) surveillance data from 2001-2016. Pneumonia and otitis media cases were calculated assuming a relative proportion to IPD. Cases and costs (2016 GBP, 3.5% discounted) were calculated over a 5-year period for the entire UK population. Scenario analyses were undertaken to evaluate the impact of parameter uncertainty.
RESULTS: Compared with maintaining the 2+1 schedule, reducing to 1+1 was predicted to incur 8,561-25,394 additional cases of pneumococcal disease, 249-665 more deaths, and £9.9-£26.8MM additional disease-related medical costs (Table 1) across all age groups over the 5-year period. Serotype 19A IPD was responsible for 77-95% of incremental cases.
CONCLUSION: Results suggest that removal of an infant priming dose would increase pneumococcal disease cases and medical costs compared with maintaining a 2+1 schedule, with much of this increase from resurgence in 19A. It is important that policymakers consider potential public health impact when considering modifications to vaccination strategies.