Uptrend prevalence of varicella parallel with low serum antibodies and low second-dose rate among children 10-14 years old in Wenzhou, China.

In recent years, the incidence of varicella cases is rising, and outbreaks of varicella are frequently being reported worldwide. Our study aims to analyze the association between the varicella incidence and serum antibody level in the post-vaccine era. We retrieved and analyzed the incidence and prevalence data for children age 1-14 years in Wenzhou, China during 2010-2018. A cross-sectional seroepidemiology analysis was carried out in a series of 168 general healthy children age 1-14 years as well as children at a varicella outbreak in Wenzhou. Our data showed a significant surge in the incidence and prevalence of varicella in children aged 10-14 years in 2017 and 2018 while they were kept relatively stable in 2010-2016. The seroepidemiological analysis revealed a 7.3-fold significantly higher level of serum varicella IgG in healthy control students who exposed at the outbreak than that in general healthy children (median 523.5 vs. 71.7 mIU/mL, p < .01). The children 10-14 years old had the lowest rate of second-dose vaccination among the three age classes (7%, 41%, and 65% in 10-14, 5-9, and 2-4 age class, respectively), and children 5-9 years old who received the second dose had a higher level of serum protective IgG than those who did not (254.7 vs 98 mIU/mL, p = .06). The findings from the present study warn a two-dose vaccine schedule to reduce the climbing incidence and prevalence observed in the older children and suggest a higher serum IgG threshold for effective protection of children from the varicella outbreak.

[Risk assessment indexes for shellfish poisoning outbreak caused by red tide].

OBJECTIVE: To establish the indexes and weights of risk assessment of shellfish poisoning outbreak caused by red tide. METHODS: The risk assessment indexes were developed with the methods of literature review, brainstorm and expert consultation, and the weights of indexes were calculated by the method of analytic hierarchy process. The established indexes contained the risk possibility, impacts of public health, population vulnerability and resilience. The relative risk indexes(integrated risk indexes) of different shellfish poisoning were computed by combining hierarchy process and TOPSIS methods. Moreover, the weights of indexes were further used to generate absolute risk values by multiplying indexes. RESULTS: Four primary indexes and 17 secondary indexes were identified for risk assessment of shellfish poisoning outbreak. Of 17 secondary indexes, the knowing rate of shellfish poisoning, medical accessibility, the number of people being affected, laboratory testing capacity and the habits of eating seafood of local residents had relatively large weights (0.0876, 0.0840, 0.0716, 0.0703 and 0.0644, respectively), which accounted for nearly 38% of the total weight. All consistency ratio (CR) were less than 0.1. The index system was applied in Cangnan county of Zhejiang province. The results showed the relative risk indexes of paralytic shellfish poisoning (PSP), diarrhetic shellfish poisoning (DSP), neurotoxic shellfish poisoning (NSP) and amnesic shellfish poisoning (ASP) were 0.4526, 0.7116, 0.1657 and 0.2884, and the absolute risk values were 0.2542, 0.2668, 0.1907 and 0.2184, respectively. The risk orders of the 4 kinds of shellfish poisoning sorted by relative risk indexes and absolute risk values were consistent. CONCLUSIONS: The indexes and weights of risk assessment of shellfish poisoning outbreak caused by red tide are established, which can provide scientific advice for prevention and control of shellfish poisoning outbreak.

Epidemiological Features of Hand, Foot and Mouth Disease during the Period of 2008-14 in Wenzhou, China.

This study aimed to analyze the epidemiological characteristics of hand, foot and mouth disease (HFMD) during 2008-14 in Wenzhou, China. The epidemiological data of HFMD retrieved from the Wenzhou Center for Disease Control and Prevention were retrospectively analyzed. HFMD infections with enterovirus 71 (EV71), Cox A16 or other pathogens were further verified by polymerase chain reaction (PCR) and real-time PCR. A total of 213 617 cases of HFMD were reported between 2008 and 2014 in Wenzhou. The average incidence was 384.31 of 100 000, and the fatality rate was 0.14‰. The incidence of HFMD peaked between April and July, and it occurred more frequently in males than in females. Approximately 92.68% of the HFMD patients were children aged <5 years. Nearly 80% of the cases were diagnosed within 2 days after onset. The major HFMD pathogen was EV71. This study suggested that appropriate comprehensive prevention and control measures should be taken to avoid the spread of HFMD.

[Epidemiological Analysis of Malaria in Wenzhou City during 2007-2014].

A total of 258 malaria cases with 2 deaths were reported during 2007-2014, including 148 vivax malaria cases, 106 falciparum malaria cases, and 4 ovale malaria cases. During 2007-2009, 86.0% (135/157) were vivax malaria cases with 3 indigenous cases. In 2010-2014, the proportion of falciparum malaria is increasing year by year, and all were imported cases. 98.8% were imported from Africa and other provinces in China. Most cases occurred among patients aged 20-49 years, and the male-to-female ratio was 3.16:1. Most patients were workers and commercial service personnel. The malaria epidemic situation is relatively stable in Wenzhou. Malaria control and elimination interventions should emphasize the monitoring and education of transient population to control the imported cases, and explore multi-sector coordination for malaria prevention and control.

[Epidemiological analysis of malaria in Wenzhou City in 2013].

OBJECTIVE: To understand the characteristics of malaria prevalence in Wenzhou City in 2013, so as to provide the evidence for improving the elimination program of malaria. METHODS: The epidemiological data of malaria in Wenzhou City in 2013 were collected from the Chinese information system for disease control and prevention, and analyzed with the descriptive epidemiological methods for epidemiological characteristics of malaria. RESULTS: Totally 34 imported malaria cases were reported in Wenzhou City in 2013 with the incidence of 0.37 per 100,000 people. Plasmodiumfalciparum, P. ovale and P. vivax were identified in 31, 1 and 2 cases, respectively. No death cases were reported, and 64.71% (22/34) of the cases were reported in Cangnan County, Lucheng District and Rui' an City. The malaria cases were mostly concentrated in persons aged 20-49 years with male to female sex ratio at 4.67: 1, and the predominant portion of cases were workers and commercial service personnel. Totally 97.06% of the cases were imported from Africa. CONCLUSIONS: The malaria endemic situation is relatively stable and no local malaria cases are reported in Wenzhou City in 2013. In order to achieve the goal of malaria elimination, the management and education of the transient population should be strengthened.

[Semi-quantitative risk assessment on local transmission of Dengue fever caused by introduced cases].

OBJECTIVE: To assess the risk of local transmission of Dengue caused by introduced cases with semi-quantitative method in 2015 in Zhejiang Province. METHODS: Risk indexes of local transmission of Dengue caused by introduced cases were reviewed. The weights of indexes were computed by analytic hierarchy process and further used to generate absolute risk values by multiplying indexes. Moreover, comprehensive indexes were computed to describe relative risk by combining analytic hierarchy process and TOPSIS methods. RESULTS: Four primary indexes and 19 secondary indexes were identified for risk assessment of local transmission of Dengue. The indexes with maximum and minimum weight were the number of immigration from countries with Dengue patients (weight value: 0.0678) and density of population (weight value: 0.0371) respectively. All CR values, statistics for measuring consistency of score matrix, were less than 0.1 (minimum: 0.000, maximum: 0.0922, average: 0.0251). The absolute risk of Zhejiang Province was within the range of 0.397-0.504 (the full score was 1.0). The risk orders of 11 municipalities sorted by relative comprehensive indexes and absolute risk values methods were similar. The three highest municipalities were Hangzhou, Wenzhou and Ningbo and the ranges of absolute risk value were 0.387-0.494, 0.404-0.511 and 0.392-0.499 respectively. CONCLUSION: The results provides scientific basis for preventing and controlling Dengue in Zhejiang Province. The indexes and weights may be used to assess risk of Dengue in future. In addition, the semi-quantitative method constructed in this study would be a significant reference for risk assessment of public health in emergencies.