Seroepidemiology of human enterovirus71 and coxsackievirusA16 in Jiangsu province, China.

BACKGROUND: The major etiology of hand, foot and mouth disease (HFMD) is infection with human enterovirus A (HEV-A). Among subtypes of HEV-A, coxsackievirusA16 (CoxA16) and enterovirus 71 (EV71) are major causes for recurrent HFMD among infants and children in Jiangsu Province, mainland China. Here, we analyzed maternal antibodies between prenatal women and their neonates, to determine age-specific seroprevalence of human EV71 and CoxA16 infections in infants and children aged 0 to 15 years. The results may facilitate the development of immunization against HFMD. METHODS: This study used cross-section of 40 pairs of pregnant women and neonates and 800 subjects aged 1 month to 15 years old. Micro-dose cytopathogenic effects measured neutralizing antibodies against EV71 and CoxA16. Chi-square test compared seroprevalence rates between age groups and McNemar test, paired-Samples t-test and independent-samples t-test analyzed differences of geometric mean titers. RESULTS: A strong correlation between titers of neutralizing antibody against EV71 and CoxA16 in prenatal women and neonates was observed (rEV71 = 0.67, rCoxA16 = 0.56, respectively, p < 0.05). Seroprevalence rates of anti-EV71 antibody gradually decreased with age between 0 to 6 months old, remained low between 7 to 11 months (5.0-10.0%), and increased between 1 and 4 years (22.5-87.5%). Age-specific seroprevalence rates of anti-EV71 antibody stabilized in >80% of children between 5 to 15 years of age. However, seroprevalence rates of anti-CoxA16 antibody were very low (0.0-13.0%) between 0 to 6 months of age, gradually increased between 7 months to 4 years (15.0-70.0%), and stabilized at 54.0% (108/200) between 5 to 15 years. Seroprevalence rates against EV71 and CoxA16 were low under 1 year (0.0-10.0%), and showed an age dependent increase with high seroprevalence (52.5-62.5%) between 4 and 10 years of age. CONCLUSIONS: Concomitant infection of EV71 and CoxA16 was common in Jiangsu Province. Therefore, development of bivalent vaccine against both EV71 and CoxA16 is critical. The optimal schedule for vaccination may be 4 to11 months of age.

Impact of non-pharmaceutical interventions on the incidences of vaccine-preventable diseases during the COVID-19 pandemic in the eastern of China.

BACKGROUND: In response to the coronavirus disease 2019 (COVID-19) pandemic, many countries have implemented mitigating non-pharmaceutical interventions. We investigated the impact of these interventions and changes in public behavior on the incidences of selected vaccine-preventable diseases (VPDs) during the COVID-19 pandemic in the eastern of China. METHODS: From routine monitoring data collected in the capital of eastern China's Jiangsu Province, we extracted and analyzed the incidences of influenza; hand, foot and mouth disease (HFMD); varicella; mumps; pertussis; and hepatitis B. We also investigated the changes in public behavior during the COVID-19 pandemic through telephone interviews and questionnaire surveys. RESULTS: Compared with the baseline (2017-2019), the incidences of all VPDs except influenza declined significantly in 2020 (HFMD decreased by 79.92%, varicella decreased by 7.71%, mumps decreased by 2.03%, pertussis decreased by 78.91%, and hepatitis B decreased by 0.31%). The reduction in reported cases in children (0-14 years) was greater than that in adults, and pertussis had the largest reduction (approximately 80%) in children. Influenza peaks in winter; in the three years before the COVID-19 pandemic, Influenza rates took an average of 10 weeks to recede to their lowest levels after the Spring Festival, while in 2020, this took only 1 week. A total of 366 outbreaks with 20,205 cases were reported during the COVID-19 pandemic. Among the participants in the study, 94.2% of the interviewees avoided going to high-risk areas, 82.4% avoided going to crowded places, 92.9% wore masks when going out,88.4% washed their hands frequently, and 67.9% maintained social distance. CONCLUSIONS: Our study showed significant reductions in the incidences of VPDs after the implementation of a series of non-pharmaceutical interventions during the COVID-19 pandemic.

Spatiotemporal Dynamics of Hand-Foot-Mouth Disease and Its Relationship with Meteorological Factors in Jiangsu Province, China.

Hand, foot and mouth disease (HFMD) is an important public health issue in mainland China, including Jiangsu Province. The main purpose of this study was to depict the epidemiological characteristics of HFMD and evaluate the effects of meteorological variables on its dynamics via spatiotemporal analytic methods, which is essential for formulating scientific and effective prevention and control strategies and measures. In total, 497,910 cases of HFMD occurred in the 2009-2013 period, with an average annual incidence of 126.3 per 100,000 in Jiangsu. Out of these, 87.7% were under 5 years old with a male-to-female incidence ratio of 1.4. The dominant pathogens of the laboratory-confirmed cases were EV71 and CoxA16, accounting for 44.8% and 30.6% of all cases, respectively. Two incidence peaks were observed in each year, the higher occurring between April and June, the lower between November and December. The incidence ranged between 16.8 and 233.5 per 100,000 at the county level. The incidence in the South of the province was generally higher than that in the northern regions. The most likely spatiotemporal cluster detected by space-time scan analysis occurred in May-June of 2012 in the southern region. Average temperature and rainfall were positively correlated with HFMD incidence, while the number of days with rainfall ≥ 0.1mm, low temperature, high temperature and hours of sunshine were negatively related. Particularly, relative humidity had no relationship. In conclusion, the prevalence of HFMD in Jiangsu Province has an obvious feature of seasonality. The etiological composition changed dynamically and might be a latent driving force for the temporal variation of the incidence of HFMD. A moderately warm environment promotes the transmission of the HFMD viruses, while particularly cold and hot climate conditions restrain their transmission.

[Epidemiological characteristics and temporal-spatial clustering analysis on hand-foot-mouth disease in Jiangsu province, 2009 - 2011].

OBJECTIVE: To analyze the epidemic characteristics of hand-foot-mouth disease (HFMD) in Jiangsu province. METHODS: We downloaded the case-data of HFMD in Jiangsu province during 2009 - 2011 from the Chinese National Notifiable Infectious Disease Reporting System, and made a comprehensive analysis on the epidemiological features of it with descriptive epidemiological methods and retrospective space-time permutation scan statistics. RESULTS: A total of 285 414 cases were reported in Jiangsu, from 2009 to 2011, with an annual incidence of 122.66 per 100 000. There were 3686 severe cases in the 3 years a cumulatively, accounting for 1.29% of the total. Proportion of the cases being 5 years old or even younger was 93.64%. Scatteredly living children accounted for 64.08% of the total cases and 78.65% of the severe cases, respectively. The epidemics of HFMD were visible in each city of Jiangsu province, with a lowest annual incidence rate of 44.02 per 100 000 and a highest one up to 202.90 per 100 000. Regions as Suzhou, Nanjing, Wuxi had the highest incidence in the province, with cases in these three areas occupying almost 40% of all. The numbers of severe cases in Suqian and in Yancheng cities increased by 339.22% and 328.33% in 2011 compared to in 2010, respectively, and the rates of increase in these two cities were much higher than those in the other regions. Two peaks of incidence were observed every year, with the highest occurring between April and June and the second occurring in November. The spatial-temporal distribution of HFMD was not random in Jiangsu province, from 2009 to 2011. Clusters for general cases in August and 7 clusters for severe cases were detected, respectively. 12 359 cases of HFMD were laboratory confirmed in the said 3 years, including 10 414 common cases and 1945 severe cases. EV71 and CoxA16 accounted for 43.49% and 37.07% of common cases, respectively. In terms of the severe cases, the ratios were 80.82% and 5.96%, respectively. CONCLUSION: HFMD was highly endemic in Jiangsu province, and the situation of prevention and control for it is still grim. Scatteredly living children of 5 years old or younger were the major population at risk, and the epidemic in different regions and seasons was different. EV71 and CoxA16 were the major etiologic agents, but the etiologic constitute showed seasonal changes.

[Epidemiology and etiology of hand-foot-and-mouth disease seen in Jiangsu province from 2008 to 2010].

OBJECTIVE: To analyze the etiological and epidemiological characteristics of hand-foot-and-mouth disease (HFMD) seen in Jiangsu province from 2008 to 2010, and provide evidence for its prevention and control. METHODS: Based on the requirement of supervision program of HFMD, surveillance and report were done according to National Disease Supervision Information Management System. Descriptive epidemiological method, performed between 2008 and 2010, was used to analyze the time, region and population distribution and results of etiologic analysis of HFMD. Nucleic acid of enterovirus (EV) genome was detected by real-time RT-PCR. RESULTS: The average incidence rate of HFMD was 86.70 per million between 2008 and 2010, the peak incidence occurred in April to July. There were significant differences among the incidence in different districts (P<0.05), and the highest incidence was seen in the densely inhabited southern areas of Jiangsu province. Most of the cases were infants and children aged less than 5 years. The number of male cases (2008: 17,008, 2009: 48 768, 2010: 50,231) was much larger than that of the female cases 2008: 9662, 2009: 29 151, 2010: 30,655. The HFMD cases with mild symptoms were caused mainly by enterovirus 71 (EV71) and coxsackievirus A16 (Cox A16) and there was difference among different years. The severe HFMD cases and deaths were mainly caused by EV71 infection. CONCLUSIONS: The epidemiologic characteristics of HFMD in Jiangsu province from 2008 to 2010 had close relationship with season, population and region. The mild cases of HFMD were mainly infected with EV71 and Cox A16. However, EV71 illness seemed to be more severe and had significantly greater frequency of serious complications and fatality than the illness caused by Cox A16.