PREDICTING THE IMPACT OF PCV13 ON INVASIVE PNEUMOCOCCAL DISEASE (IPD) IN MAINLAND CHINA
China is one of few countries yet to introduce PCV. We aimed to estimate the long-term impact of a PCV13 programme on childhood IPD in mainland China, accounting for provincial heterogeneity.
A Bayesian hierarchical model was fit to systematic review data on the proportion of vaccine-type IPD and carriage in each province. A mechanistic model was then used to predict the relative reduction in IPD incidence of a PCV13 programme, assuming VT circulation is eventually interrupted and replaced by NVTs.
Across China, we estimate that a median 75% (95% HDI: 53 – 90%) of carriage and 88% (95% HDI: 76 - 94%) of IPD is caused by vaccine serotypes. A mature PCV programme would lead to a median 51% (95% HDI: -40 – 81%) reduction in the incidence of IPD, ranging from 33% in Hubei (95% HDI: -34 – 76%) to a median 76% in Beijing (95% HDI: 44 – 92%). All 95% credible intervals for province-level covariate effects contain zero for VT carriage and IPD, and as such the impact estimates in provinces with little or no serotype distribution data remain uncertain.
PCV13 has the potential to substantially reduce the pneumococcal disease burden in China, but data to underpin the estimates is sparse in Western China.