Effectiveness of DTaP Against Pertussis in ≤2-Year-Old Children — Linyi Prefecture, Shandong Province, China, 2017–2019
Pinpin Zhu, Dan Wu, Yan Wang, Xiaoxue Liu, Lance E. Rodewald, Yixing Li, Hui Zheng, Lei Cao, Yifan Song, Song Li, Xiaodong Zhao, Jianyi Yao, Fuzhen Wang, Mingshuang Li, Qian Zhang, Tingting Yan, Zundong Yin
Abstract
What is already known about this topic?: Vaccine effectiveness (VE) is positively correlated with the number of administered co-purified diphtheria, tetanus, and acellular pertussis vaccine (DTaP) doses. A matched case-control study conducted in Zhongshan City revealed that the co-purified DTaP VE against pertussis-related illnesses in children aged 4-11 months was 42% for one dose, 88% for two doses, and 95% for three doses, respectively. What is added by this report?: The results of this study contribute to the current body of research. We found that the VE of co-purified DTaP against pertussis-related illness and hospitalization increased substantially, ranging from 24%-26% after one dose to 86%-87% after four doses. What are the implications for public health practice?: The results of this study underscore the significance of prompt and comprehensive immunization using co-purified DTaP to decrease the incidence of pertussis. Additionally, these findings offer evidence supporting the modification of China's pertussis vaccination approach.