Spatial-temporal analysis of hepatitis B in Fujian Province, China in 2012-2021.

Background: Fujian Province has one of the highest reported incidences of hepatitis B virus infection in China. This study aimed to provide a theoretical framework for preventing and controlling hepatitis B in Fujian Province, and to assess the trends and the spatial-temporal distribution patterns of hepatitis B in this region. Methods: Data on hepatitis B cases were extracted from the National Notifiable Infectious Disease Surveillance System. Spatial autocorrelation analysis, trend surface analysis, and spatial-temporal scanning statistics were used to identify the spatial and aggregation patterns at the county level. The Joinpoint was used to assess the reported incidence trends. Results: The average reported incidence of hepatitis B in Fujian from 2012 to 2021 was 14.46/10,000 population, with 583,262 notified cases. The age-adjusted reported incidence of hepatitis B decreased from 17.44/10,000 population in 2012 to 11.88/10,000 population in 2021, with an average reduction in the annual percentage change of 4.5%. There were obvious spatial-temporal aggregation characteristics in hepatitis B cases, and a high-incidence area was located in eastern Fujian. Spatio-temporal scanning statistics revealed four levels of aggregation of hepatitis B reporting rates. The first level of aggregation area included Minhou, Gulou, Jin'an, Taijiang, and nine other districts and counties. Conclusion: The incidence of hepatitis B is declining in Fujian Province. Spatial clusters of hepatitis B cases in Fujian Province were identified, and high-risk areas in eastern Fujian still exist. Closely monitoring the general patterns in the occurrence of hepatitis B and implementing focused control and preventative strategies are important.

Model-based risk assessment of dengue fever transmission in Xiamen City, China.

Background: Quantitative assessment of the risk of local transmission from imported dengue cases makes a great challenge to the development of public health in China. The purpose of this study is to observe the risk of mosquito-borne transmission in Xiamen City through ecological and insecticide resistance monitoring. Quantitative evaluation of mosquito insecticide resistance, community population and the number of imported cases affecting the transmission of dengue fever (DF) in Xiamen was carried out based on transmission dynamics model, so as to reveal the correlation between key risk factors and DF transmission. Methods: Based on the dynamics model and combined with the epidemiological characteristics of DF in Xiamen City, a transmission dynamics model was built to simulate the secondary cases caused by imported cases to evaluate the transmission risk of DF, and to explore the influence of mosquito insecticide resistance, community population and imported cases on the epidemic situation of DF in Xiamen City. Results: For the transmission model of DF, when the community population is between 10,000 and 25,000, changing the number of imported DF cases and the mortality rate of mosquitoes will have an impact on the spread of indigenous DF cases, however, changing the birth rate of mosquitoes did not gain more effect on the spread of local DF transmission. Conclusions: Through the quantitative evaluation of the model, this study determined that the mosquito resistance index has an important influence on the local transmission of dengue fever caused by imported cases in Xiamen, and the Brayton index can also affect the local transmission of the disease.

Impact of public health and social measures on contact dynamics during a SARS-CoV-2 Omicron variant outbreak in Quanzhou, China, March to April 2022.

OBJECTIVES: To evaluate the impact of early implementation of public health and social measures (PHSMs) on contact rates over time and explore contact behavior of asymptomatic versus symptomatic cases. METHODS: We used the largest contact tracing data in China thus far to estimate the mean contacts over time by age groups and contact settings. We used bootstrap with replacement to quantify the uncertainty of contact matrixes. The Pearson correlation was performed to demonstrate the number of contacts over time in relation to the evolution of restrictions. In addition, we analyzed the index cases with a high number of contacts and index cases that produced a high number of secondary cases. RESULTS: Rapidly adapted PHSMs can reduce the mean contact rates in public places while increasing the mean contact rates within households. The mean contact rates were 11.81 (95% confidence interval, 11.61-12.01) for asymptomatic (at the time of investigation) cases and 6.70 (95% confidence interval, 6.54-6.87) for symptomatic cases. The percentage of asymptomatic cases (at the time of investigation) meeting >50 close contacts make up more than 65% of the overall cases. The percentage of asymptomatic cases producing >10 secondary cases account for more than 80% of the overall cases. CONCLUSION: PHSMs may increase the contacts within the household, necessitating the need for pertinent prevention strategies at home. Asymptomatic cases can contribute significantly to Omicron transmission. By making asymptomatic people aware that they are already contagious, hence limiting their social contacts, it is possible to lower the transmission risk.

Epidemiological characteristics of viral hepatitis E in Fujian Province from 2012 to 2021 / 中国热带医学

@#Abstract: Objective To analyze the epidemiological characteristics of viral hepatitis E in Fujian Province from 2012-2021, and to provide scientific evidence for the prevention and control of hepatitis E in the future. Methods Descriptive epidemiological method was used to analyze hepatitis E cases in Fujian Province from 2012 to 2021. Results From 2012 to 2021, a total of 8 877 cases of hepatitis E were reported in Fujian Province from 2012-2021. The overall incidence rate showed a decreasing trend (χ2trend =458.14, P<0.001), with the lowest incidence rate of 1.32/100 000 in 2020 and an annual average incidence rate of 2.29/100 000 per year. The incidence was higher in winter and spring, with the months of March and April having the highest number of reported cases (2 146, 24.17%) and the fewest cases were reported in September (571, 6.43%). The difference in reported incidence rates between cities was statistically significant (χ2=1 877.75, P<0.01). The comprehensive experimental zone of Pingtan had the highest average reported incidence rate of 6.03/100 000, while Zhangzhou had the lowest at 0.94/100 000. The number of male cases was higher than the number of female cases, with a male to female ratio of 2.04∶1. The disease was most prevalent among middle-aged and elderly individuals, with the age group of 40-<65 years having the highest number of reported cases, accounting for 57.44% (5 099/8 877) of all cases. The age group of 50-<55 years had the highest reported incidence, with the number of reported cases increasing with age below 50 years, but decreasing with age over 50 years. As for occupational distribution, peasants had the highest proportion of the disease, accounting for 34.49% (3 062 cases) of the total cases. Conclusions The reported incidence rate of hepatitis E in Fujian showed a downward from 2012 to 2021. Due to the impact of COVID-19, incidence of the lowest was 2020, but it did not reflect the true situation of the disease, which may have affected trend of hepatitis E. In order to control and reduce the incidence of hepatitis E, efforts should be made to increase publicity and education on health knowledge and vaccination among key areas and populations, strengthen monitoring and diagnostic capability, and implement comprehensive prevention and control measures.

Inactivated vaccine effectiveness against symptomatic COVID-19 in Fujian, China during the Omicron BA.2 outbreak.

Objective: More than 90% of the Chinese population have completed 2 doses of inactivated COVID-19 vaccines in Mainland China. However, after China government abandoned strict control measures, many breakthrough infections appeared, and vaccine effectiveness against Omicron BA.2 infection was uncertain. This study aims to investigate the real-world effectiveness of widely used inactivated vaccines during the wave of Omicron variants. Methods: Test-negative case-control study was conducted in this study to analyze the vaccine effectiveness against symptomatic disease caused by the Omicron variant (BA.2) in Fujian, China. Conditional logistic regression was selected to estimate the vaccine effectiveness. Results: The study found the vaccine effectiveness against symptomatic COVID-19 is 32.46% (95% CI, 8.08% to 50.37%) at 2 to 8 weeks, and 27.05% (95% CI, 1.23% to 46.12%) at 12 to 24 weeks after receiving booster doses of the inactivated vaccine. Notably, the 3-17 years group had higher vaccine effectiveness after 2 doses than the 18-64 years and over 65 years groups who received booster doses. Conclusion: Inactivated vaccines alone may not offer sufficient protection for all age groups before the summer of 2022. To enhance protection, other types of vaccines or bivalent vaccines should be considered.

Study on the interaction between different pathogens of Hand, foot and mouth disease in five regions of China.

Objectives: This study aims to explore the interaction of different pathogens in Hand, foot and mouth disease (HFMD) by using a mathematical epidemiological model and the reported data in five regions of China. Methods: A cross-regional dataset of reported HFMD cases was built from four provinces (Fujian Province, Jiangsu province, Hunan Province, and Jilin Province) and one municipality (Chongqing Municipality) in China. The subtypes of the pathogens of HFMD, including Coxsackievirus A16 (CV-A16), enteroviruses A71 (EV-A71), and other enteroviruses (Others), were included in the data. A mathematical model was developed to fit the data. The effective reproduction number (R eff ) was calculated to quantify the transmissibility of the pathogens. Results: In total, 3,336,482 HFMD cases were collected in the five regions. In Fujian Province, the R eff between CV-A16 and EV-A71&CV-A16, and between CV-A16 and CV-A16&Others showed statistically significant differences (P < 0.05). In Jiangsu Province, there was a significant difference in R eff (P < 0.05) between the CV-A16 and Total. In Hunan Province, the R eff between CV-A16 and EV-A71&CV-A16, between CV-A16 and Total were significant (P < 0.05). In Chongqing Municipality, we found significant differences of the R eff (P < 0.05) between CV-A16 and CV-A16&Others, and between Others and CV-A16&Others. In Jilin Province, significant differences of the R eff (P < 0.05) were found between EV-A71 and Total, and between Others and Total. Conclusion: The major pathogens of HFMD have changed annually, and the incidence of HFMD caused by others and CV-A16 has surpassed that of EV-A71 in recent years. Cross-regional differences were observed in the interactions between the pathogens.

Modelling the Emerging COVID-19 Epidemic and Estimating Intervention Effectiveness - Taiwan, China, 2021.

INTRODUCTION: The coronavirus disease 2019 (COVID-19) pandemic recently affected Taiwan, China. This study aimed to calculate the transmissibility of COVID-19 to predict trends and evaluate the effects of interventions. METHODS: The data of reported COVID-19 cases was collected from April 20 to May 26, 2021, which included daily reported data (Scenario I) and reported data after adjustment (Scenario II). A susceptible-exposed-symptomatic-asymptomatic-recovered model was developed to fit the data. The effective reproductive number (Reff ) was used to estimate the transmissibility of COVID-19. RESULTS: A total of 4,854 cases were collected for the modelling. In Scenario I, the intervention has already taken some effects from May 17 to May 26 (the Reff reduced to 2.1). When the Reff was set as 0.1, the epidemic was projected to end on July 4, and a total of 1,997 cases and 855 asymptomatic individuals would have been reported. In Scenario II, the interventions were projected as having been effective from May 24 to May 26 (the Reff reduced to 0.4). When the Reff was set as 0.1, the epidemic was projected to end on July 1, and a total of 1,482 cases and 635 asymptomatic individuals would have been reported. CONCLUSION: The epidemic of COVID-19 was projected to end after at least one month, even if the most effective interventions were applied in Taiwan, China. Although there were some positive effects of intervention in Taiwan, China.

Long-term clinical prognosis of human infections with avian influenza A(H7N9) viruses in China after hospitalization.

BACKGROUND: Mainland China has experienced five epidemics of human cases of avian influenza A(H7N9) virus infection since 2013. We conducted a prospective study to assess long-term clinical, pulmonary function testing, and chest computed tomography (CT) imaging findings after patients were discharged from hospital. METHODS: A(H7N9) survivors in five provinces and one municipality underwent follow-up visits from August 2013 to September 2018, at three, six, and 12 months after illness onset, and a subset was also assessed at 18 and 64 months after onset. Thirteen patients were enrolled from the first A(H7N9) epidemic in 2013, 36 from the 2013-2014 second epidemic, and 12 from the 2016-2017 fifth epidemic. At each visit, A(H7N9) survivors received a medical examination, including the mMRC (modified Medical Research Council) dyspnea scale assessment, chest auscultation, pulmonary function testing and chest CT scans. FINDINGS: The median age of 61 A(H7N9) survivors was 50 years. The cumulative rate of pulmonary dysfunction was 38·5% and 78·2% for chest CT scan abnormalities at the end of follow-up. Restrictive ventilation dysfunction was common during follow-up. Mild dyspnea was documented at three to 12-month follow-up visits. INTERPRETATION: Patients who survived severe illness from A(H7N9) virus infection had evidence of persistent lung damage and long-term pulmonary dysfunction. FUNDING: National Science Fund for Distinguished Young Scholars (grant number 81525023); Program of Shanghai Academic/Technology Research Leader (grant number 18XD1400300); National Science and Technology Major Project of China (grant numbers 2017ZX10103009-005, 2018ZX10201001-010).

Epidemiology of avian influenza A H7N9 virus in human beings across five epidemics in mainland China, 2013-17: an epidemiological study of laboratory-confirmed case series.

BACKGROUND: The avian influenza A H7N9 virus has caused infections in human beings in China since 2013. A large epidemic in 2016-17 prompted concerns that the epidemiology of the virus might have changed, increasing the threat of a pandemic. We aimed to describe the epidemiological characteristics, clinical severity, and time-to-event distributions of patients infected with A H7N9 in the 2016-17 epidemic compared with previous epidemics. METHODS: In this epidemiological study, we obtained information about all laboratory-confirmed human cases of A H7N9 virus infection reported in mainland China as of Feb 23, 2017, from an integrated electronic database managed by the China Center for Disease Control and Prevention (CDC) and provincial CDCs. Every identified human case of A H7N9 virus infection was required to be reported to China CDC within 24 h via a national surveillance system for notifiable infectious diseases. We described the epidemiological characteristics across epidemics, and estimated the risk of death, mechanical ventilation, and admission to the intensive care unit for patients admitted to hospital for routine clinical practice rather than for isolation purpose. We estimated the incubation periods, and time delays from illness onset to hospital admission, illness onset to initiation of antiviral treatment, and hospital admission to death or discharge using survival analysis techniques. FINDINGS: Between Feb 19, 2013, and Feb 23, 2017, 1220 laboratory-confirmed human infections with A H7N9 virus were reported in mainland China, with 134 cases reported in the spring of 2013, 306 in 2013-14, 219 in 2014-15, 114 in 2015-16, and 447 in 2016-17. The 2016-17 A H7N9 epidemic began earlier, spread to more districts and counties in affected provinces, and had more confirmed cases than previous epidemics. The proportion of cases in middle-aged adults increased steadily from 41% (55 of 134) to 57% (254 of 447) from the first epidemic to the 2016-17 epidemic. Proportions of cases in semi-urban and rural residents in the 2015-16 and 2016-17 epidemics (63% [72 of 114] and 61% [274 of 447], respectively) were higher than those in the first three epidemics (39% [52 of 134], 55% [169 of 306], and 56% [122 of 219], respectively). The clinical severity of individuals admitted to hospital in the 2016-17 epidemic was similar to that in the previous epidemics. INTERPRETATION: Age distribution and case sources have changed gradually across epidemics since 2013, while clinical severity has not changed substantially. Continued vigilance and sustained intensive control efforts are needed to minimise the risk of human infection with A H7N9 virus. FUNDING: The National Science Fund for Distinguished Young Scholars.

Risk Factors for Influenza A(H7N9) Disease in China, a Matched Case Control Study, October 2014 to April 2015.

Background. Human infections with avian influenza A(H7N9) virus have been associated with exposure to poultry and live poultry markets (LPMs). We conducted a case-control study to identify additional and more specific risk factors. Methods. Cases were laboratory-confirmed A(H7N9) infections in persons in China reported from October 1, 2014 to April 30, 2015. Poultry workers, those with insufficient data, and those refusing participation were excluded. We matched up to 4 controls per case by sex, age, and residential community. Using conditional logistic regression, we examined associations between A(H7N9) infection and potential risk factors. Results. Eighty-five cases and 334 controls were enrolled with similar demographic characteristics. Increased risk of A(H7N9) infection was associated with the following: visiting LPMs (adjusted odds ratio [aOR], 6.3; 95% confidence interval [CI], 2.6-15.3), direct contact with live poultry in LPMs (aOR, 4.1; 95% CI, 1.1-15.6), stopping at a live poultry stall when visiting LPMs (aOR, 2.7; 95% CI, 1.1-6.9), raising backyard poultry at home (aOR, 7.7; 95% CI, 2.0-30.5), direct contact with backyard poultry (aOR, 4.9; 95% CI, 1.1-22.1), and having ≥1 chronic disease (aOR, 3.1; 95% CI, 1.5-6.5). Conclusions. Our study identified raising backyard poultry at home as a risk factor for illness with A(H7N9), suggesting the need for enhanced avian influenza surveillance in rural areas.

[Role of syndromic surveillance program in the practice of early detection on disease outbreak].

OBJECTIVE: A Dengue outbreak was reported in Dongfen town Jianou county, Fujian province on September 19, 2014. The goal of this project was to explore the role of syndromic surveillance program in the practice of early detection on disease outbreak through the case mentioned above. METHODS: The authors retrospectively collected data related to Outpatient log and Pharmacy drug use in Dongfen township hospital through the electronic information system of the hospital from August to November, 2014. All the abnormal events were recorded, according to related data on fever and drug use. Description of fever, syndromic characteristics, correlation and Linear regression analyses were conducted, using the surveillance data on fever syndrome and drug use from the pharmacy. RESULTS: A total of 1 102 cases with fever and 2 437 fever-related clinic visits were reported which showing an increased number of 19.6, 10.2 times respectively, when compared to the same period of the previous year in which men accounted for 45.3% (499/1 102) and female accounted for 54.7% (603/1 102). Age groups presented an atypical type " M" type. 5 and 10 year olds groups formed the largest proportion, accounted for 11.5% (127/1 102) of the total number os the patients. The correlation coefficient ranged from 0.85 to 0.97 (P<0.05). Data from the syndromic surveillance program showed an " outbreak" was occured in August 23, 2014. CONCLUSIONS: Compared to routine surveillance program, the syndromic surveillance program could detect the appearence of an outbreak, a month or even more earlier. The role of syndromic surveillance program needs to be further explored.