Assessing vaccination coverage, timeliness, and its temporal variations among children in a rural area in China

China has achieved high vaccination coverage under the Expanded Program on Immunization (EPI) in children 1–2 years of age. However, a knowledge gap exists regarding vaccination coverage and timeliness for children >2 years of age. As such, this study aimed to estimate coverage and timeliness for all EPI and selected non-EPI vaccines within a rural area of China. Immunization data for 5091 children, born between September 2003 and November 2015, were collected from vaccination cards obtained during sero-surveillance follow-up visits and/or from the Hunan immunization information system. For each dose of both EPI and non-EPI vaccines, vaccination coverage and timeliness were calculated, and temporal variations were examined across birth cohorts. We found coverage for EPI vaccines scheduled for <12 months was 97.1%-99.4%. However, for EPI vaccines scheduled at 6 years coverage was 44.4%-51.7%. The timeliness for EPI vaccines was generally poor, especially for EPI vaccines introduced after 2008 or scheduled for administration at ≥12 months, with a maximum of 35.4% of children vaccinated according to schedule. Despite this, we found increasing trends in vaccination coverage and improvements in timeliness for EPI vaccines. However, for non-EPI vaccines, we found only moderate increases, and in some cases decreases, in vaccination coverage. This study demonstrates the success and improvement of the Chinese immunization program, but also highlights some challenges to be addressed. We recommend that future changes in vaccine practice and policy should primarily focus on improving coverage and timeliness of vaccines introduced after 2008, and/or scheduled for administration ≥12 months

Comparison of epidemiological features between imported and indigenous dengue cases in China

Objective: to analyze the epidemiological characteristics of dengue fever in 2016 and compare the difference between imported and indigenous dengue fever cases in China, and provide evidence for the development of national strategies for dengue fever prevention and control. Methods: the incidence data of dengue fever were obtained from national notifiable communicable disease reporting information system to describe the demographic and epidemiological characteristics of the dengue fever, and the spatiotemporal patterns were compared between imported and indigenous cases, and the imported sources of dengue fever were also presented. Results: in 2016, a total of 2 049 dengue fever cases were reported without death in China, a decrease of 46.9% compared with 2015. The incidence rate was 0.2/100 000. Among the reported cases, 1 569 were indigenous cases (76.6%). A total of 1 562 local cases were reported in Fujian (921 cases), Guangdong (416 cases), Yunnan (217 cases) and Zhejiang (8 cases); and 7 cases from other provinces were reported by Guangxi and Hunan (2 cases respectively), and Shandong, Shaanxi and Zhejiang (1 case respectively). A total of 480 imported cases were reported in 23 provinces, accounting for 23.4% of total cases, in which 434 were from Southeast Asia and South Asia, accounting for 90.4% of total imported cases. Conclusion: the incidence of dengue fever was significantly lower in China in 2016 compared with 2015, and the indigenous outbreaks in provinces with high incidence history were mainly caused by imported cases. The significant difference in epidemiological characteristics has been found between indigenous and imported cases. Therefore, it is necessary to improve the dengue fever control strategy according to the characteristics of indigenous and imported dengue fever cases

Variation in Influenza B Virus Epidemiology by Lineage, China

We used national sentinel surveillance data in China for 2005–2016 to examine the lineage-specific epidemiology of influenza B. Influenza B viruses circulated every year with relatively lower activity than influenza A. B/Yamagata was more frequently detected in adults than in children

Seasonal and interannual risks of dengue introduction from South-East Asia into China, 2005-2015

International audienceDue to worldwide increased human mobility, air-transportation data and mathematical models have been widely used to measure risks of global dispersal of pathogens. However, the seasonal and interannual risks of pathogens importation and onward transmission from endemic countries have rarely been quantified and validated. We constructed a modelling framework, integrating air travel, epidemiological, demographical, entomological and meteorological data, to measure the seasonal probability of dengue introduction from endemic countries. This framework has been applied retrospectively to elucidate spatiotemporal patterns and increasing seasonal risk of dengue importation from SouthEast Asia into China via air travel in multiple populations, Chinese travelers and local residents, over a decade of 2005-15. We found that the volume of airline travelers from SouthEast Asia into China has quadrupled from 2005 to 2015 with Chinese travelers increased rapidly. Following the growth of air traffic, the probability of dengue importation from SouthEast Asia into China has increased dramatically from 2005 to 2015. This study also revealed seasonal asymmetries of transmission routes: Sri Lanka and Maldives have emerged as origins; neglected cities at central and coastal China have been increasingly vulnerable to dengue importation and onward transmission. Compared to the monthly occurrence of dengue reported in China, our model performed robustly for importation and onward transmission risk estimates. The approach and evidence could facilitate to understand and mitigate the changing seasonal threat of arbovirus from endemic regions

Changing geographic patterns and risk factors for avian influenza A(H7N9) infections in humans, China

The fifth epidemic wave of avian influenza A(H7N9) virus in China during 2016-2017 demonstrated a geographic range expansion and caused more human cases than any previous wave. The factors that may explain the recent range expansion and surge in incidence remain unknown. We investigated the effect of anthropogenic, poultry, and wetland variables on all epidemic waves. Poultry predictor variables became much more important in the last 2 epidemic waves than they were previously, supporting the assumption of much wider H7N9 transmission in the chicken reservoir. We show that the future range expansion of H7N9 to northern China may increase the risk of H7N9 epidemic peaks coinciding in time and space with those of seasonal influenza, leading to a higher risk of reassortments than before, although the risk is still low so far.SCOPUS: ar.jinfo:eu-repo/semantics/publishe