Prevalence of Haemophilus influenzae type b infection in Chinese children: a systematic review and meta-analysis

Abstract

BackgroundHaemophilus influenzae type b is an important cause of invasive bacterial disease in children worldwide. The establishment of epidemiological estimates is an essential first step towards the introduction of H influenzae type b vaccine into the Chinese national immunisation programme. We therefore undertook a systematic review and meta-analysis to estimate the prevalence of H influenzae type b in Chinese children. MethodsWe systematically searched PubMed, Web of Science, CNKI, Wanfang, and Ovid databases for studies published up to Dec 31, 2016, that reported the prevalence of H influenzae type b among children in mainland China. We used random-effects meta-analysis to obtain the pooled prevalence of H influenzae type b in healthy children and in those with acute lower respiratory tract infection or bacterial meningitis. Findings27 studies met prespecified inclusion criteria, and these included 15 783 children in 14 provinces. The pooled prevalence of H influenzae type b in healthy children, children with acute lower respiratory tract infection, and bacterial meningitis was 5·87% (95% CI 3·42–8·33), 4·06% (3·29–4·83), and 27·32% (0·41–54·24), respectively. Meta-regression showed that the prevalence of H influenzae type b in healthy children remained stable after the introduction of H influenzae type b vaccine in 1997 (p=0·725), whereas the proportion of children with acute lower respiratory tract infection due to H influenzae type b showed a decreasing trend (P<0·0001) and was higher in northern China than in the south (p<0·0001). Significant heterogeneity was noted across and within regions (P<0·0001). Differences in sex, age groups, and study sample size did not explain the heterogeneity. InterpretationH influenzae type b is a common pathogen in healthy children and an important cause of lower respiratory tract infection and bacterial meningitis in China. Introduction of H influenzae type b vaccine into the Chinese national immunisation programme could reduce the burden of H influenzae type b disease in China. FundingUNICEF China Office.