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Introduction Two types of Japanese encephalitis (JE) vaccines, inactivated JE vaccine (JE-I) and live-attenuated JE vaccine (JE-L), are available and used in China. In particular, one JE-L, produced by a domestic manufacturer in China, was prequalified by WHO in 2013. We assessed the safety of JE vaccines in China during 2008–2013 using the Chinese National Adverse Events Following Immunization Information System (CNAEFIS) data. Methods We retrieved AEFI reporting data about JE vaccines from CNAEFIS, 2008–2013, examined demographic characteristics of AEFI cases, and used administrative data on vaccine doses as denominator to calculate and compare crude reporting rates. We also used disproportionality reporting analysis between JE-I and JE-L to assess potential safety signals. Results A total of 34,879 AEFIs related with JE-I and JE-L were reported, with a ratio of male to female as 1.3:1; 361 (1.0%) cases were classified as serious. JE vaccines were administered concurrently with one or more other vaccines in 13,592 (39.0%) of cases. The overall AEFI reporting rates were 214.4 per million vaccination doses for JE-L and 176.9 for JE-I (rate ratio [RR]: 1.2, 95% confidence interval [CI]: 1.1–1.3) in 2010–2013. Febrile convulsions (FC) following JE-I was found as a signal of disproportionate reporting (SDR). However, there was no significant difference between the reporting rates of FC of JE-I and JE-L (0.3 per million vaccination doses for JE-L, 0.4 for JE-I, p = 0.05). Conclusions While our analysis did not find apparent safety concern of JE vaccines in China, further study should consider JE-I vaccines and febrile convulsion, and taking more sensitive methods to detect signals.

“Wa, Wa,….” The silence in a CoV (clinic of vaccination) is broken by a child’s piercing cry….

BACKGROUND The national Adverse Events Following Immunization (AEFI) surveillance system in China (CNAEFIS) has collected AEFI reports -including deaths following all vaccines used in China since 2008. AIMS To review reports of AEFI-associated death cases from 2010 to 2015 to assess potential vaccine safety issues. METHODS Descriptive analysis of epidemiologic characteristic of AEFI-associated death cases and standard causality assessment for reported causes of deaths. To estimate the risk of death after vaccination, we used population data, administered doses and live births to calculate denominators. RESULTS During 2010-2015, 753 deaths were reported to CNAEFIS from mainland China. Highest numbers were reported in 2013 and 2014 when reporting peak of AEFI-associated deaths occurred after media reports concerning "death following Hepatitis B vaccination" in China. About 95% of deaths were in children

BACKGROUND: China reduced hepatitis B virus (HBV) infection by 90% among children under 5 years old with safe and effective hepatitis B vaccines (HepB). In December 2013 this success was threatened by widespread media reports of infant deaths following HepB administration. Seventeen deaths and one case of anaphylactic shock following HBV vaccination had been reported. METHODS: We conducted a telephone survey to measure parental confidence in HepB in eleven provinces at four points in time; reviewed maternal HBV status and use of HepB for newborns in birth hospitals in eight provinces before and after the event; and monitored coverage with hepatitis B vaccine and other programme vaccines in ten provinces. RESULTS: HepB from the implicated company was suspended during the investigation which showed that the deaths were not caused by HepB vaccination. Before the event 85% respondents regarded domestic vaccines as safe decreasing to 26.7% during the event. During the height of the crisis 30% of parents reported being hesitant to vaccinate and 18.4% reported they would refuse HepB. Use of HepB in the monitored provinces decreased by 18.6% from 53 653 doses the week before the event to 43 688 doses during the week that Biokangtai HepB was suspended. Use of HepB within the first day of life decreased by 10% among infants born to HBsAg-negative mothers and by 6% among infants born to HBsAg-positive mothers. Vaccine refusal and HepB birth dose rates returned to baseline within 2 months; confidence increased but remained below baseline. CONCLUSIONS: The HBV vaccine event resulted in the suspension of a safe vaccine which was associated with a decline of parental confidence and refusal of vaccination. Suspension of a vaccine can lead to loss of confidence that is difficult to recover. Timely and credible investigation accompanied by proactive outreach to stakeholders and the media may help mitigate negative impact of future coincidental adverse events following immunization. (c) The Author 2016; all rights reserved. Published by Oxford University Press on behalf of the International Epidemiological Association.

Surveillance for adverse events following immunization (AEFI) is an important component of any national immunization program. In the People's Republic of China (China), a populous, middle-income country, development of an AEFI surveillance system began in 2005. In 2008, the AEFI surveillance system was implemented as a nationwide, online system and called the Chinese National AEFI Information System (CNAEFIS). Since then, CNAEFIS has provided useful, national-level data on vaccine safety. National AEFI surveillance guidelines were issued jointly by the Ministry of Health and the China Food and Drug Administration in 2010. This article reviews the development, status, and key aspects of the Chinese AEFI surveillance system, and describes challenges and future plans for vaccine safety assessment in China.

Introduction Vaccine-associated paralytic poliomyelitis (VAPP) is one of the most important adverse effects of vaccines that are in current use globally. The Chinese national adverse event following immunization information system (CNAEFIS) is a passive surveillance system which collects data on VAPP. Aims To describe the epidemiological characteristics of VAPP and estimate the risk of recipient VAPP in China. Methods We retrieved information from reported cases of recipient VAPP from CNAEFIS from 2010 to 2015, examined the demographic characteristics of the cases, and used administrative data on vaccination doses and the estimated number of births as denominators to calculate VAPP incidence. Results During 2010–2015, 157 cases of recipient VAPP were reported to CNAEFIS (male-to-female ratio, 8.2:1); 151 cases (96.2%) were less than six months old. All cases were associated with trivalent OPV (tOPV), and 89.8% occurred after the receipt of first dose. Of the 157 recipient VAPP cases, type II, type III, and type I poliovirus vaccine strains were isolated from 27 (17.2%) , 25 (15.9%) , and 16 (10.2%) cases, respectively. One case died and one case recovered completely; the other 155 cases had various physical disabilities, such as monolateral or bilateral limping. Using the administered doses of OPV as the denominator, the incidence of recipient VAPP during the study period was estimated at 0.4 per million doses. The estimated recipient VAPP per million births ranged from 1.0 to 2.4 during 2010–2015. Conclusion The epidemiological characteristics of recipient VAPP cases in China, such as age distribution, were comparable to those in previous studies from other countries. The risk of recipient VAPP, using either estimated births or vaccination doses, was comparable to that in the US and Japan. We recommend using an inactive poliovirus vaccine to decrease the number of recipient VAPP cases in China.

On September 21, 2009, China began administering vaccines, obtained from 10 different manufacturers, against 2009 pandemic influenza A (H1N1) virus infection in priority populations. We aimed to assess the safety of this vaccination program.We designed a plan for passive surveillance for adverse events after immunization with the influenza A (H1N1) vaccine. Physicians or vaccination providers were required to report the numbers of vaccinees and all adverse events to their local Center for Disease Control and Prevention (CDC), which then reported the data to the Chinese CDC through the online National Immunization Information System's National Adverse Event Following Immunization Surveillance System. Data were collected through March 21, 2010, and were verified and analyzed by the Chinese CDC.A total of 89.6 million doses of vaccine were administered from September 21, 2009, through March 21, 2010, and 8067 vaccinees reported having an adverse event, for a rate of 90.0 per 1 million doses. The age-specific rates of adverse events ranged from 31.4 per 1 million doses among persons 60 years of age or older to 130.6 per 1 million doses among persons 9 years of age or younger, and the manufacturer-specific rates ranged from 4.6 to 185.4 per 1 million doses. A total of 6552 of the 8067 adverse events (81.2%; rate, 73.1 per 1 million doses) were verified as vaccine reactions; 1083 of the 8067 (13.4%; rate, 12.1 per 1 million doses) were rare and more serious (vs. common, minor events), most of which (1050) were allergic reactions. Eleven cases of the Guillain-Barré syndrome were reported, for a rate of 0.1 per 1 million doses, which is lower than the background rate in China.No pattern of adverse events that would be of concern was observed after the administration of influenza A (H1N1) vaccine, nor was there evidence of an increased risk of the Guillain-Barré syndrome.