No abstract

CD4 þ CD25 þ regulatory T cells (Treg) are potent immunosuppressive cells active in controlling normal pathological immune responses. The mechanisms of this suppression have been investigated under various conditions. In this report, tumor necrosis factor-related apoptosis inducing ligand (TRAIL)/death receptor 5 (DR5) was explored as one of the pivotal factors for the suppression and cytotoxicity induced by CD4 þ CD25 þ Treg. Cell death was involved in the suppression induced by activated CD4 þ CD25 þ Treg in vitro. The induction of CD4 þ T cell death was not mediated by the CD95/CD95L pathway, but rather depended upon the upregulation of TRAIL in the Treg. Blocking the TRAIL/DR5 pathway resulted in a significant reduction of the suppressive activity as well as the cytotoxic effects of Treg in vitro. Activated Treg displayed TRAIL-dependent cytotoxicity against CD4 þ T cells in vivo. The prolonged survival of allogeneic skin grafts induced by Treg was inhibited by DR5-blocking antibodies. Our findings suggest that the TRAIL/DR5 pathway is one of the mechanisms used by Treg to regulate immune responses both in vitro and in vivo.

BackgroundOutbreaks of human infection with a new avian influenza A H7N9 virus occurred in China in the spring of 2013. Control and prevention of a new human infectious disease outbreak can be strongly affected by public reaction and social impact through the Internet and social media.ObjectiveThis study aimed to investigate the potential roles of Internet surveillance in control and prevention of the human H7N9 outbreaks.MethodsOfficial data for the human H7N9 outbreaks were collected via the China National Health and Family Planning Committee website from March 31 to April 24, 2013. We obtained daily posted and forwarded number of blogs for the keyword “H7N9” from Sina microblog website and a daily Baidu Attention Index (BAI) from Baidu website, which reflected public attention to the outbreak. Rumors identified and confirmed by the authorities were collected from Baidu search engine.ResultsBoth daily posted and forwarded number and BAI for keyword H7N9 increased quickly during the first 3 days of the outbreaks and remained at a high level for 5 days. The total daily posted and forwarded number for H7N9 on Sina microblog peaked at 850,000 on April 3, from zero blogs before March 31, increasing to 97,726 on April 1 and to 370,607 on April 2, and remaining above 500,000 from April 5-8 before declining to 208,524 on April 12. The total daily BAI showed a similar pattern of change to the total daily posted and forwarded number over time from March 31 to April 12. When the outbreak locations spread, especially into other areas of the same province/city and the capital, Beijing, daily posted and forwarded number and BAI increased again to a peak at 368,500 and 116,911, respectively. The median daily BAI during the studied 25 days was significantly higher among the 7 provinces/cities with reported human H7N9 cases than the 2 provinces without any cases (P<.001). So were the median daily posted and forwarded number and daily BAI in each province/city except Anhui province. We retrieved a total of 32 confirmed rumors spread across 19 provinces/cities in China. In all, 84% (27/32) of rumors were disseminated and transmitted by social media.ConclusionsThe first 3 days of an epidemic is a critical period for the authorities to take appropriate action through Internet surveillance to prevent and control the epidemic, including preparation of personnel, technology, and other resources; information release; collection of public opinion and reaction; and clarification, prevention, and control of rumors. Internet surveillance can be used as an efficient and economical tool to prevent and control public health emergencies, such as H7N9 outbreaks.

No 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...

No abstract

Middle East Respiratory Syndrome (MERS), a pandemic threat to human beings, has aroused huge concern worldwide, but no bibliometric studies have been conducted on MERS research. The aim of this study was to map research productivity on the disease based on the articles indexed in PubMed. The articles related to MERS dated from 2012 to 2015 were retrieved from PubMed. The articles were classified into three categories according to their focus. Publication outputs were assessed and frequently used terms were mapped using the VOS viewer software. A total of 443 articles were included for analysis. They were published in 162 journals, with Journal of Virology being the most productive (44 articles; 9.9%) and by six types of organizations, with universities being the most productive (276 articles; 62.4%).The largest proportion of the articles focused on basic medical sciences and clinical studies (47.2%) and those on prevention and control ranked third (26.2%), with those on other focuses coming in between (26.6%). The articles on prevention and control had the highest mean rank for impact factor (IF) (226.34), followed by those on basic medical sciences and clinical studies (180.23) and those on other focuses (168.03). The mean rank differences were statistically significant (p = 0.000). Besides, “conronavirus”, “case”, “transmission” and “detection” were found to be the most frequently used terms. The findings of this first bibliometric study on MERS suggest that the prevention and control of the disease has become a big concern and related research should be strengthened.

Hepatitis E virus is a common hepatotropic virus that causes serious gastrointestinal symptoms. Data of reported HEV cases in Zhejiang Province was collected between 2007 and 2012. Descriptive epidemiological methods and spatial-temporal epidemiological methods were used to investigate the epidemiological trends and identify high-risk regions of hepatitis E infection. In this study, the average morbidity of hepatitis E infection was 4.03 per 100,000 in Zhejiang Province, peaking in winter and spring. The ratio between the male and the female was 2.39:1, and the high-risk population was found to be aged between 40 and 60. Trend surface analysis and IDW maps revealed higher incidences in the northwestern counties. The spatial-temporal analysis showed comparable incidences in the counties at the basins of three rivers, mostly under administration of Hangzhou Municipality. Besides, the seasonal exponential smoothing method was determined as the better model for the retrieved data. The epidemiological characteristics of HEV suggested the need of strengthened supervision and surveillance of sanitary water, sewage treatment and food in high-risk areas especially around the Spring Festival. Additionally, time series model could be useful for forecasting the epidemics of HEV in future. All these findings may contribute to the prevention and control of HEV epidemics.