Epidemiological Characteristics and Spatial-Temporal Clusters of Hand, Foot, and Mouth Disease in Zhejiang Province, China, 2008-2012

Abstract

Hand, foot and mouth disease (HFMD) is one of the major public health concerns in China. Being the province with high incidence rates of HFMD, the epidemiological features and the spatial-temporal patterns of Zhejiang Province were still unknown. The objective of this study was to investigate the epidemiological characteristics and the high-incidence clusters, as well as explore some potential risk factors. The surveillance data of HFMD during 2008–2012 were collected from the communicable disease surveillance network system of Zhejiang Provincial Center for Disease Control and Prevention. The distributions of age, gender, occupation, season, region, pathogen’s serotype and disease severity were analyzed to describe the epidemiological features of HFMD in Zhejiang Province. Seroprevalence survey for human enterovirus 71 (EV71) in 549 healthy children of Zhejiang Province was also performed, as well as 27 seroprevalence publications between 1997 and 2015 were summarized. The spatial-temporal methods were performed to explore the clusters at county level. Furthermore, pathogens’ serotypes such as EV71 and coxsackievirus A16 (Cox A16) and meteorological factors were analyzed to explore the potential factors associated with the clusters. A total of 454,339 HFMD cases were reported in Zhejiang Province during 2008–2012, including 1688 (0.37%) severe cases. The annual average incidence rate was 172.98 per 100,000 (ranged from 72.61 to 270.04). The male-to-female ratio for mild cases was around 1.64:1, and up to 1.87:1 for severe cases. Of the total cases, children aged under three years old and under five years old accounted for almost 60% and 90%, respectively. Among all enteroviruses, the predominant serotype was EV71 (49.70%), followed by Cox A16 (26.05%) and other enteroviruses (24.24%) for mild cases. In severe cases, EV71 (82.85%) was the major causative agent. EV71 seroprevalence survey in healthy children confirmed that occult infection was common in children. Furthermore, literature summary for 26 seroprevalence studies during 1997–2015 confirmed that 0–5 years group showed lowest level of EV71 seroprevalence (29.1% on average) compared to the elder children (6–10 years group: 54.6%; 11–20 years group: 61.8%). Global positive spatial autocorrelation patterns (Moran’s Is>0.25, P<0.05) were discovered not only for mild cases but also for severe cases, and local positive spatial autocorrelation patterns were revealed for counties from the eastern coastal and southern regions. The retrospective space-time cluster analysis also confirmed these patterns. Risk factors analyses implied that more EV71 and less sunshine were associated with the clusters of HFMD in Zhejiang Province. Our study confirmed that Zhejiang Province was one of the highly epidemic provinces in China and that the epidemiological characteristics of HFMD were similar to other provinces. Occult infection in elder children and adults was one of the important reasons why most HFMD cases were children aged under-five. Combining the results of spatial a...

Epidemiology of 45,616 suspect cases of Hand, Foot and Mouth Disease in Chongqing, China, 2011–2015

“…Their incidences increased with age until 2 years and then started to decrease. Children aged more than 6 years were seldom attacked by this disease, which was consistent with reports from other areas of China222324252627. However, our results show that the HFMD population with the highest morbidity was the 2-year age group, which was different from the 1-year age group reported in the earlier epidemiology of HFMD21.…”

Enterovirus 71 infection impairs the reproductive capacity of female mice

“…HFMD typically occurs in children <5 years old, and EV71 and coxsackie virus A16 have been identified as the primary causes of HFMD (2). Serious neurological complications and fatalities are associated with EV71 (24).…”

“…Therefore, effective vaccines that protect against EV71-associated HFMD or herpangina are important (25). Currently, two monovalent EV71 vaccines have been marketed in mainland China (2). However, clinical data concerning their effectiveness is not yet available.…”

“…Enterovirus (EV) 71 is a member of the picornaviridae family of viruses that contain single-stranded positive-sense RNA (1), which primarily infects children <5 years old (2). Infants with EV71 infection develop sores on their hands, feet, buttocks and mouth; therefore, the infection is referred to as hand, foot and mouth disease (HFMD) (3).…”

Enterovirus 71 structural viral protein 1 promotes mouse Schwann cell autophagy via endoplasmic reticulum stress-mediated peripheral myelin protein 22 upregulation

“…HFMD is an emerging public health issue worldwide, especially in Asia-Pacific countries(1, 3, 4). Although HFMD is commonly considered as a self-limited disease characterized by ulcerating vesicles in the mouth and viral rashes on hands and feet(5–7), a small proportion of cases are severe and even fatal due to cardiopulmonary or neurological complications(8, 9). EV71 infection accounts for at least 80% of severe cases and 90% of deaths in China according to the recent data (10).…”