Epidemiological characteristics and temporal-spatial clustering analysis of hand, foot and mouth disease in Nanchang city 2008–2012

Mapping of space-time patterns of infectious disease using spatial statistical models: a case study of COVID-19 in India

INTRODUCTION

Mapping of infectious diseases like COVID-19 is the foremost importance for diseases control and prevention. This study attempts to identify the spatio-temporal pattern and evolution trend of COVID-19 at the district level in India using spatial statistical models.

MATERIALS AND METHODS

Active cases of eleven time-stamps (30 March-2 December, 2020) with an approximately 20-day interval are considered. The study reveals applications of spatial statistical tools, i.e. optimised hotspot and outlier analysis (which follow Gi* and Moran I statistics) and emerging hotspot with the base of space time cube, are effective for the spatio-temporal evolution of disease clusters.

RESULTS

The result shows the overall increasing trend of COVID-19 infection with a Mann-Kendall trend score of 2.95 (p = 0.0031). The spatial clusters of high infection (hotspots) and low infection (coldspots) change their location over time but are limited to the districts of the south-western states (Kerala, Karnataka, Andhra Pradesh, Maharashtra, Gujarat) and the north-eastern states (West Bengal, Jharkhand, Assam, Tripura, Manipur, etc.) respectively.

CONCLUSIONS

A total of eight types of patterns are identified, but the most concerning types are consecutive (7.24% of districts), intensifying (15.13% districts) and persistent (24.34% of districts) which will help health policy makers and the government to prioritize-based resource allocation and control measures.

Short-term effects of extreme meteorological factors on childhood hand, foot, and mouth disease reinfection in Hefei, China: A distributed lag non-linear analysis

BACKGROUND

Hand, foot, and mouth disease (HFMD) is a major public health issue in China with a high burden of reinfection. Previous studies presented evidence of the relationship between meteorological factors and HFMD incidence, but no study examined the effects of extreme meteorological factors on HFMD reinfection.

METHODS

Daily HFMD reinfection counts and meteorological data of Hefei city were collected from 2011 to 2016. A distributed lag non-linear model was used to quantify the effects of extreme weather (wind speed, sunshine duration, and precipitation) on HFMD reinfection. All effects were presented as relative risk (RR), with 90th or 10th percentiles of meteorological variables compare with their median values. Confounding factors, such as mean temperature, relative humidity, day of week, and long-term trend were controlled.

RESULTS

A total of 4873 HFMD reinfection cases aged 0-11 years were reported. Extremely high precipitation, low wind speed, and low sunshine duration increased HFMD reinfection risk. The effect of extremely high precipitation was greatest at 8 days lag (RR = 1.01, 95%CI: 1.00-1.02). Extremely low wind speed and low sunshine increased 19% (RR = 1.19, 95%CI: 1.09-1.32) and 12% (RR = 1.12, 95%CI: 1.00-1.26) risk at lag 0-12 days, respectively. By contrast, extremely high wind speed and high sunshine duration exerted certain protective effects on HFMD reinfection at lag 0-12 days (RR = 0.76, 95%CI: 0.66-0.88; RR = 0.88, 95%CI: 0.79-0.99, respectively). Subgroup analyses showed that nursery children were the most sensitive people to the extreme wind speed and sunshine duration. Children aged 4-11 years appeared to be more susceptible to extreme sunshine duration than children aged <3 years.

CONCLUSION

The present study provides evidence that extreme meteorological factors exert delayed effects on HFMD reinfection. Developing an early warning system is necessary for the protection of children from harm due to extreme meteorological factors.

The dynamics of the hand, foot and mouth disease epidemic from 2008 to 2016 in Zhenjiang city, China

AIM

To investigate the hand, foot and mouth disease (HFMD) epidemic in Zhenjiang, China from 2008 to 2016.

MATERIALS & METHODS

A total of 37,202 HFMD cases were investigated and 3707 nasopharyngeal swabs were detected for enterovirus RNA using RT-quantitative PCR.

RESULTS

We first reported a mixed pattern of HFMD seasonal epidemic with a combination of single-peak and two-peak patterns in alternate years, and the occurrence of sporadic and epidemic outbreaks of HFMD in kindergartens in Zhenjiang. Children younger than 4 years of age were highly vulnerable to HFMD, and home children and boys had higher risk to develop severe HFMD than nursery children and girls, respectively. Among tested samples, 1709 (46.1%) were detected as enterovirus RNA positive.

CONCLUSION

This study first presents the dynamic of the HFMD epidemic in Zhenjiang from 2008 to 2016.

Spatio-temporal analysis of the relationship between meteorological factors and hand-foot-mouth disease in Beijing, China

Background

Hand-foot-mouth disease (HFMD) is a common infectious disease in China and occurs mostly in infants and children. Beijing is a densely populated megacity, in which HFMD has been increasing in the last decade. The aim of this study was to quantify spatio-temporal characteristics of HFMD and the relationship between meteorological factors and HFMD incidence in Beijing, China.

Methods

Daily counts of HFMD cases from January 2010 to December 2012 were obtained from the Beijing Center for Disease Prevention and Control (CDC). Seasonal trend decomposition with Loess smoothing was used to explore seasonal patterns and temporal trends of HFMD. Bayesian spatiotemporal Poisson regression models were used to quantify spatiotemporal patterns of HFMD incidence and associations with meteorological factors.

Results

There were 114,777 HFMD cases reported to Beijing CDC from 1 January 2010 to 31 December 2012 and the raw incidence was 568.6 per 100,000 people. May to July was the peak period of HFMD incidence each year. Low-incidence townships were clustered in central, northeast and southwest regions of Beijing. Mean temperature, relative humidity, wind velocity and sunshine hours were all positively associated with HFMD. The effect of wind velocity was significant with a RR of 3.30 (95%CI: 2.37, 4.60) per meter per second increase, as was sunshine hours with a RR of 1.20 (95%CI: 1.02, 1.40) per 1 hour increase.

Conclusions

The distribution of HFMD in Beijing was spatiotemporally heterogeneous, and was associated with meteorological factors. Meteorological monitoring could be incorporated into prediction and surveillance of HFMD in Beijing.

Electronic supplementary material

The online version of this article (10.1186/s12879-018-3071-3) contains supplementary material, which is available to authorized users.

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.