Impact of Immunization Programs on 11 Vaccine-Preventable Diseases in China: 1950-2018

Abstract

Background: China’s immunization program has determined dramatic declines in morbidity and mortality of vaccine-preventable diseases (VPDs) in the past decades. To evaluate the program’s achievements, we explored the changes in morbidity and mortality of VPDs in China. Methods: 11 diseases were chosen as representative notifiable diseases in China, and annual surveillance data obtained between 1950 and 2018 were used to derive trends in morbidity and mortality for each stage. Quasi-Poisson regression models and Polynomial regression models were used to estimate the impacts of specific vaccine programs, and life-table methods were used to calculate the loss of life expectancy, years of life lost (YLLs) and loss of working years. Results: The total notification number for the 11 VPDs was 211,866,000 from 1950 to 2018. The greatest number occurred in 1959, with around 12 million cases and a total incidence rate of 1,723 per 100,000 persons. The quasi-Poisson regression models showed that most of the 11 diseases revealed dramatic declines in morbidity after integrating into Expanded Program on Immunization (EPI), while varicella, and paratyphoid fever showed an increased morbidity, which did not integrate into EPI in China. From 1978 to 2018, the incidence rate of pertussis fell 98% from 126.35 to 1.58 per million, that of measles fell 99% from 249.76 to 0.28 per 100,000, that of meningococcal meningitis fell 99% from 32.23 to 0.01 per million, that of JE fell 98% from 5.39 to 0.13 per million, and diphtheria and polio were eradicated, with the last cases being reported in 2006 and 1994, respectively. From 1978 to 2018, the total life expectancy for the 11 VPDs increased by 0.79 years. Interpretation: China had great success in controlling VPDs in recent decades, and the burden of major diseases has been declining. The implementation of the National Immunization Program (NIP) accelerated the decreases in morbidity and mortality rates. Improving vaccination coverage is a key aspect of controlling VPDs in China. Funding Statement: This study was funded by the “Evaluation project on national immunization program of China” Declaration of Interests: The authors declare that they have no competing interest.