OBJECTIVETo investigate the epidemiological and clinical features of hand, foot and mouth disease (HFMD) since several outbreaks of HFMD caused by enteroviruses were documented in China between 2007 and 2008.

METHODSHFMD cases reported to the National Infectious Disease Information Management System database between May 2008 and April 2009 were assessed. Clinical features in some of the severe and fatal cases were analyzed the etiology of the outbreaks was investigated.

RESULTS89.1% of reported HFMD cases were found in children<5 year-old with an age-specific incidence rate of 834.1/100 000 in the first year as the notifiable disease in China from May 2008 to April 2009. The incidence, mortality and percentage of severe cases were studied for three regions of China and found to be highest in the central region. The incidence of severe cases and mortality in rural population were significantly higher than those in urban population. Among the laboratory confirmed EV17 positive cases there were 52.6% mild, 83.5% severe, and 96.1% fatal cases. More myoclonic jerks were found in the severe case group than in group that died. Tachypnea, lip purpling, pink foaming and low limb temperature occurred more frequently in the fatal cases than in the severe cases.

CONCLUSIONThe epidemic of HFMD in China was characterized predominantly by EV71 infections, had relatively high mortality rates especially in the central region, and was most prevalent in young, rural populations.

Adolescent ; Adult ; Aged ; Aged, 80 and over ; Child ; Child, Preschool ; China ; epidemiology ; Hand, Foot and Mouth Disease ; epidemiology ; pathology ; Humans ; Infant ; Infant, Newborn ; Middle Aged ; Young Adult

Objective:To understand the epidemiological characteristics and risk factors of fatal cases of hand, foot, and mouth disease (HFMD) in children under 5 years old in China from 2008 to 2018, and provide evidence for the development of targeted prevention and control measures and reduction of the incidence of fatal HFMD cases.Methods:The incidence data of reported HFMD cases in China during 2008-2018 were collected from the National Notifiable Disease Surveillance Reporting System of China for the analyses on the demographic characteristics, spatial distribution, diagnosis or reporting and pathogen spectrum of the HFMD cases. Then the risk factors causing deaths were analyzed by using logistic regression model.Results:From 2008 to 2018, a total of 3 646 fatal cases of HFMD in children under 5 years old were reported in China. There were more fatal HFMD cases in boys than in girls (1.82∶1), the death mainly occurred in age group 0 to 2 years (87.71%). Adjusted mortality rate of HFMD in children under 5 years old in China declined from 0.87 per 100 000 in 2010 to 0.11 per 100 000 in 2018 (APC=-23.20%). In the 2 523 laboratory-confirmed deaths, 2 323 (92.07%) were EV-A71 infections, but the constituents of CV-A16 and other enterovirus infections increased. The interval from onset to diagnosis M=2( P25-P75:2 -4)d. The interval from onset to death M=3( P25-P75:2 -4)d. Age between 0 and 1 years, EV-A71 infection, longer interval between onset and diagnosis, and living in rural area were the risk factors causing fatal HFMD cases. Conclusions:The number of the fatal cases, the rate of mortality and case fatality HFMD in China had shown downward trends since 2010. EV-A71 is still the main pathogen causing fatal cases, but we should pay more attention to gene pattern of the other enteroviruses except EV-A71 and CV-A16. To reduce the risk of the fatal cases we should strengthen the health education about the immunization of EV-A71 inactivated vaccines and reduce the interval from onset to diagnosis in young children in western provinces and rural areas.

Objective Through analyzing the surveillance data on typhoid fever and paratyphoid fever in 2015 to understand the related epidemiological features and most possible clustering areas of high incidence.Methods Individual data was collected from the passive surveillance program and analyzed by descriptive statistic method.Characteristics on seasonal,regional and distribution of the diseases were described.Spatial-temporal clustering characteristics were estimated,under the retrospective space-time method.Results A total of 8 850 typhoid fever cases were reported from the surveillance system,with incidence rate as 0.65/100 000.The number of paratyphoid fever cases was 2 794,with incidence rate as 0.21/100 000.Both cases of typhoid fever and paratyphoid fever occurred all year round,with high epidemic season from May to October.Most cases involved farmers (39.68％),children (15.89％) and students (12.01％).Children under 5 years showed the highest incidence rate.Retrospective space-time analysis for provinces with high incidence rates would include Yurnan,Guangxi,Guizhou,Hunan and Guangdong,indicating the first and second class clusters were mainly distributed near the bordering adjacent districts and counties among the provinces.Conclusion In 2015,the prevalence rates of typhoid fever and paratyphoid fever were low,however with regional high prevalence areas.Cross regional transmission existed among provinces with high incidence rates which might be responsible for the clusters to appear in these areas.

Objective To investigate the clinical severity,etiological classification and risk factors of severe cases with hand,foot and mouth disease (HFMD).Methods A total of 1 489 records on severe and fatal HFMD cases reported to the national pilot surveillance system of HFMD were used to analyze the demographic,medical treatment,etiological classification of the cases.Treatment outcome related risk factors were also studied with multi-variable stepwise logistic regression method.Results Seven out of the 1 489 severe HFMD cases died of this disease.A total of 960 (72.9％) were under three years old and 62.9％ were male and most of the cases (937,62.9％) resided in rural areas.Among all the cases,494 (33.2％) went to seek the first medical assistance at the institutions of village or township level.Durations between disease onset and first medical attendance,being diagnosed as the disease or diagnosed as severe cases were 0(0-1) d,1 (0-2) d and 2 (1-4) d,respectively.In total,773 (51.9％) of the severe HFMD cases were diagnosed as with aseptic meningitis,260 (17.5％) with brainstem encephalitis,377 (25.3 ％) with non-brainstem encephalitis,6 (0.4％) with encephalomyelitis,1 (0.1％) with acute flaccid paralysis,4 (0.3％) with pulmonary hemorrhage/pulmonary edema and 68 (4.6％) with cardiopulmonary failure.Of the etiologically diagnosed 1 217 severe and fatal HFMD cases,642 (52.8％) were with EV71,other enterovirus 261 (21.5％),Cox A16 36 (3.0％),1 (0.1％) with both EV71 and Cox A16.However,277 (22.8％) showed negative on any pathogenic virus.Complication (Z=3.15,P=0.002) and duration between onset and diagnosed as severe cases (Z=3.95,P＜0.001) were shown as key factors related to treatment outcomes.Conclusions Most severe HFMD cases appeared in boys,especially living in the rural areas.Frequently seen complications would include aseptic meningitis,non-brainstem encephalitis and brainstem encephalitis.EV71 was the dominant etiology for severe and fatal cases.Early diagnosis and complication control were crucial,related to the treatment outcome of HFMD.

Objective:To evaluate the incidence intensity of hand, foot, and mouth disease (HFMD) in 2018/2019 season in southern China by Moving Epidemic Method (MEM), and compare the intensity among provinces, so as to provide basis for optimizing the allocation of public health resources.Methods:The weekly incidence data of HFMD of children under 5 years old in 15 provinces of southern China from March 1, 2012 to February 28, 2019 were collected from Disease Surveillance Reporting System of Chinese Center for Disease Control and Prevention, and the epidemic intensity threshold of each province in southern China during this period was calculated and evaluated by MEM.Results:In the first incidence peak of 2018/2019 HFMD season, in 15 provinces in the south China, 6 provinces (Jiangsu, Zhejiang, Jiangxi, Chongqing, Sichuan and Yunnan) reported very high incidence rates in children under 5 years old while Guangdong, Guangxi and Hainan provinces had low incidence level. In the second incidence peak, the incidences in 6 provinces (Shanghai, Jiangsu, Zhejiang, Chongqing, Sichuan and Yunnan) reached very high levels. The incidences in remaining provinces also reached medium or high levels. In most provinces, the thresholds in the first incidence peak were higher than those in the second incidence peak, but Chongqing and Sichuan were different. The results of model validation showed that the sensitivity and specificity of MEM were higher than 70% except for Hainan, Chongqing and Yunnan.Conclusions:For southern provinces with two incidence peaks in HFMD season, MEM can be used to determine the epidemic intensity thresholds of different incidence peaks by dividing the disease season to analyze the incidence intensity of HFMD in different stages. The epidemic intensity threshold established by MEM integrates the historical data, and the province (city) with extremely high epidemic level identified represents that the province (city) has an abnormal increase compared with the historical incidence level, which requires more attention from all areas and timely implementation of prevention and control measures.

Objective:To characterize the epidemiology of severe hand, foot and mouth disease (HFMD) in China from 2008 to 2018 and provide evidence for the prevention and control of severe HFMD.Methods:The incidence data of severe HFMD cases from 2008 to 2018 were collected from the National Notifiable Infectious Diseases Reporting System of Chinese Center for Disease Control and Prevention. Descriptive epidemiological methods were used to analyze distributions, pathogen constituent and change of severe HFMD. Joinpoint regression model was used to analyze the trends of severity rate, proportion of severe cases and severe fatality rate.Results:From 2008 to 2018, a total of 157 065 cases of severe HFMD were reported in China, with an average annual case-severity rate of 1.05/100 000, a severe case proportion of 0.76 % and a severity-fatality rate of 2.34 %. The severity rate and the proportion of severe cases showed a downward trend after 2010, and severe fatality rate decreased significantly after 2014. The severe cases mainly occurred in infants aged ≤3 years (91.47 %), more boys were affected than girls (1.78∶1). The median age of severe HFMD cases caused by EV-A71 was highest (1.99 years) and increased year by year, other enterovirus infection cases accounted for a higher proportion in infants aged ≤1 year (66.56 %). The incidence peak occurred during April-July, other enteroviruses replaced EV-A71 as the predominant serotype in 2018 (61.97 %). The incidence of severe HFMD were high in some provinces in southwestern, central and eastern China. Conclusion:The overall severity rate, proportion of severe cases and severe fatality rate of HFMD in the mainland of China have shown a downward trend. The predominant pathogen in some provinces has changed from EV-A71 to other enteroviruses. It is necessary to strengthen the prevention and control of HFMD in key population, high incidence seasons and areas and carry out the surveillance of various pathogens of HFMD.

Hand, foot and mouth disease (HFMD) is a widespread infectious disease mainly affecting children aged five and under. In China, the current epidemic situation of HFMD remains severe, with a persistently high and increasing incidence rate, causing a substantial disease burden. A monovalent vaccine against Enterovirus A71 (EV-A71), the most common cause of severe and fatal HFMD cases, has been available in China since 2016. Although randomized controlled trials established the vaccine's efficacy among research subjects, this may not reflect the impact under "real world" conditions in the general population. Therefore, based on a systematic literature search, this paper comprehensively reviewed and analyzed relevant studies based on real-world data and collected real-world evidence about the EV-A71 vaccine on the controlling HFMD incidence. It was found that the real-world study of the EV-A71 vaccine on HFMD was few; most were limited to a province or city; there is no study comprehensively considered other important influencing factors in addition to immunization, such as temperature, relative humidity, the age structure of the population, gross domestic product, etc. The progress of using real-world data to study the impact of the EV-A71 vaccine on HFMD reviewed in this study is helpful to have a clear and comprehensive understanding of the status quo and will provide guidance and reference for future studies to assess the short-term and long-term effects of EV-A71 vaccine and other vaccines.

Objective:To analyze the nationwide epidemiological characteristics and trend of hand, foot and mouth disease (HFMD) fatal cases from 2008 to 2022 and provide evidence for the prevention and control of HFMD.Methods:The information on HFMD fatal cases during 2008 to 2022 was collected from the National Notifiable Disease Surveillance Reporting System of China. Data of the epidemiological characteristics was analyzed by R 4.2.2 software and the changing trends for the case fatality rates, mortality rates and their age-adjusted rates were analyzed by Joinpoint 4.9.10 software.Results:From 2008 to 2022, a total of 3 704 fatal HFMD cases were reported in China. The fatal cases were primarily observed in children aged <3 years (83.42%, 3 090/3 704). The male and female gender ratio was 1.82 ∶1 (2 389 ∶1 315). Regarding the age-adjusted case fatality rates over time, there was a rapid increase from 2008 to 2010 [annual percentage change (APC) =41.97%, P<0.05]. From 2010 to 2016, a steady decline was observed (APC=-28.57%, P<0.05), and the decline accelerated (APC=-39.66%, P<0.05) from 2016 to 2022. Since 2020, less than 10 fatal cases were reported annually nationwide. Among the 2 566 laboratory-confirmed deaths from 2008 to 2022, Enterovirus A71 (EV71) was the predominant pathogen (91.62%,2 351/2 566). There have been noticeable changes in the pathogen composition since 2017, decreasing in EV71 and increasing in the proportion of fatalities caused by Coxsackievirus A16 (CV-A16) and other enteroviruses. Conclusions:From 2008 to 2022, the HFMD case fatality rates and mortality rates continuously declined, peaked in 2010. Since 2017, the decline of HFMD case fatality rates has been noticeably accelerated. Along with the decrease in the proportion of EV71 in HFMD fatal cases, the proportion of other enteroviruses appeared increasing. It is essential to continuously monitor the etiological spectrum of the fatal cases.

Objective: To understand the characteristics and changes of the incidence of amoebic dysentery in China during 2015-2018, explore the causes of high incidence in some areas and provide a data base for the development of national prevention and control strategies and measures. Methods: Data were collected from the infectious disease reporting management information system from Chinese Disease Control and Prevention. To understand the seasonal, population and area distributions of amoebic dysentery, descriptive epidemiological method and software SPSS 16.0 were used to analyze the amoebic dysentery data. Results: A total of 4 366 amoebic dysentery cases were reported without death in China during 2015-2018. The reported average annual incidence was 0.08/100 000, and the overall proportion of laboratory confirmed cases was 68.23%(2 979/4 366). Amoeba dysentery mainly occurred during May to October. One seasonal peak was observed in 2015 and 2017 (July and June, respectively), and two seasonal peaks were observed in 2016 and 2018 (June and October). The patients were mainly children aged under 5 years (42.28%, 1 846/4 366), and the incidence rate decreased with age in children aged under 10 years. Of these, children under 1 years of age had the highest incidence rate (1.28/100 000). The number of cumulative reported cases in Guangxi, Henan, Guangdong, Heilongjiang and Jiangxi provinces ranked top five from 2015-2018, accounting for 64.50% (2 816/4 366) of the total. The cumulative cases in Dongxing county, Guangxi, in Suixian county, Henan and in Ranghulu district, Heilongjiang, respectively accounted for more than 50.00% of the total number of cases in their provinces. Conclusions The incidence rate of amoebic dysentery reported in China during 2015-2018 showed a decreasing trend, with a higher incidence in children under 5 years old and a higher number of cases in some areas. It is suggested to further investigate and analyze the diagnosis and reporting of amoeba dysentery in key areas and promote the update of the diagnostic standards for amoeba dysentery.

Objective: To understand the characteristics relating to the etiology and complications of hand, foot and mouth disease (HFMD) based on data from the pilot National Sentinel Surveillance (NSS) program so as to explore the feasibility, advantages and disadvantages of the NSS. Methods: Data were extracted from the NSS system, conducted in 11 provinces of China from November 2015 to October 2016. Characteristics regarding the etiology, complications of HFMD and factors related to the positive rates of HFMD specimens were analyzed under the logistic regression method by SPSS 20.0 software. Results: A total of 4 783 specimens were collected, including 3 390 from mild, 1 390 from severe and 3 from death cases. The overall positive rate was 81.43% (3 895/4 783). Other enteroviruses (non EV71/Cox A16 enteroviruses) appeared the major serotype (52.68%, 1 482/2 813) for mild infection of the disease while EV71 was for the severe cases (65.31%, 706/1 081). The serotype spectrum revealed by the pilot NSS was almost identical with the existing surveillance system. Other enteroviruses tended to infect younger children (χ²=130.17, P<0.001) than EV71 and Cox A16, in China. The multivariate logistic regression results showed that higher positive rate was associated with specimens which were collected from males, at children’ hospitals, in peak seasons, timely and in stools. The positive rates presented downwarding trends with the extension of the onset-sampling interval (χ²=14.47, P<0.001 in stool specimen; χ²=31.99, P<0.001 in throat swab; χ²=24.26, P<0.001 in anal swab). Aseptic meningitis, non-brainstem encephalitis and brainstem encephalitis appeared the top three complications of both EV71-associated and other enteroviruses-associated severe HFMD cases. Conclusions Factors as gender, season/place/timeliness of specimen collection, and types of hospital all appeared independently influenced the positive rates. NSS seemed feasible to be used as an alternative or supplement tool to the existing surveillance program in China.