Analysis of the vaccination status of enterovirus type 71 inactivated vaccine in China from 2017 to 2021 / 中华流行病学杂志

Objective: To understand the vaccination status of enterovirus type 71 (EV71) inactivated vaccines in China from 2017 to 2021 and provide evidence for making policy on immunization strategy against hand, foot and mouth disease (HFMD). Methods: Using the reported dose number of EV71 vaccination and birth cohort population data collected by the China immunizaiton program information system to estimate the cumulative coverage of EV71 vaccine by the end of 2021 among the birth cohorts since 2012 at national, provincial, and prefecture levels, and analyze the correlation between the vaccination coverage and the potential influencing factors. Results: As of 2021, the estimated cumulative vaccination coverage of the EV71 vaccine was 24.96% in birth cohorts since 2012. The cumulative vaccination coverage was between 3.09% and 56.59% in different provinces, between 0 and 88.17% in different prefectures. There was a statistically significant correlation between vaccination coverage in different regions and the region's previous HFMD prevalence and disposable income per capita. Conclusions: Since 2017, the EV71 vaccines have been widely used nationwide, but the coverage of EV71 vaccination varies greatly among regions. Vaccination coverage is higher in relatively developed regions, and the intensity of previous epidemic of HFMD may have a certain impact on the acceptance of the vaccine and the pattern of immunization service. The impact of EV71 vaccination on the epidemic of HFMD requires further studies.

Analysis on surveillance data regarding the level of Japanese encephalitis antibody in Heilongjiang. province, 2006 / 中华流行病学杂志

<p><b>OBJECTIVE</b>To study the prevalent situation of Japanese encephalitis (JE) virus among healthy people in Heilongjiang province and to analyze its risk factors.</p><p><b>METHODS</b>7 national surveillance counties were selected and divided into 5 age groups as 1-2, 3-5, 6-10, 11-20 and 21-59 years and randomly sampled 7 person in each age group per county with the sample size as 1050. Quantitative Elisa test was used to detect Japanese encephalitis antibody IgG.</p><p><b>RESULTS</b>The adjusted standard antibody positive rate of people on 1-59 year olds was 70.62%, with lowest in 3-5 age group, and increasing by age (chi2 for trend test = 40.52, P < 0.001). The overall titer of IgG was low in general population but was different with age (Kruskal-Wallis test chi2 = 76.9, P < 0.001). Older age and lower latitude seemed to be two risk factors on JE antibody IgG.</p><p><b>CONCLUSION</b>JE virus infection had a long-term effect with low level, among general population. Age and latitude were two risk factors which suggesting the necessarily of strengthening the surveillance system for JE cases at risk in the prevalent areas on Heilongjiang province.</p>