Search

On March 31, 2013, three human infections with a novel avian influenza A(H7N9) virus were identified in Shanghai and Anhui Provinces in southeastern China (1,2). As of June 30, 2013, [...]

Author(s): Mei Qu[sup.1] , Bing Lv[sup.1] , Xin Zhang[sup.1] , Hanqiu Yan[sup.1] , Ying Huang[sup.1] , Haikun Qian[sup.1] , Bo Pang[sup.2] , Lei Jia[sup.1] , Biao Kan[sup.2] and Quanyi Wang[sup.1] [...]

Background: The incidence of hand, foot, and mouth disease (HFMD) is extremely high, and has constituted a huge disease burden throughout Beijing in recent years. This study aimed to determine the spatiotemporal distribution and epidemic characteristics of HFMD.Methods: Descriptive statistics was used to analyze the data and estimate the epidemic peaks in 2009-2014. Space-time scanning detected spatiotemporal clusters and identified high-risk locations. Global and local Moran's I statistics were used to measure the spatial autocorrelation. Geocoding was performed in ArcGIS, based on the present address codes of the patients and the centroids of the towns. Maps were created in ArcGIS to show the geographic spread of HFMD.Results: In total, 220,451probable cases of HFMD were reported in Beijing between January 2009 and December 2014: 12,749 (5.78 %) were laboratory confirmed, and 35 (0.02 %) were fatal. The median age of reported cases was 3.12 years (interquartile range 1.96-4.39). Coxsackievirus A16 (CV-A16), enterovirus 71 (EV-A71), and other enteroviruses accounted for 39.31, 35.36, and 25.33 % of the 12,749 confirmed cases, respectively. Many more severe cases were caused by EV-A71 (χ (2) = 186.41, df = 1, P < 0.001) and other enteroviruses (χ (2) = 156.44, df = 1, P < 0.001) than by CV-A16. A large single distinct peak occurred between May and July each year. Spatiotemporal clusters of HFMD were identified in Beijing during 2009-2014. The most likely clusters were detected and tended to move from the southwest (Fengtai and Daxing) southeastwards to Daxing and Tongzhou in 2009-2014. The incidence of HFMD was not randomly distributed, but showed global and local spatial autocorrelations.Conclusions: There were obvious spatiotemporal clusters of HFMD in Beijing in 2009-2014. High-incidence areas mainly occurred at the junctions of urban and rural zones. More attention should be paid to the epidemiological and spatiotemporal characteristics of HFMD to establish new strategies for its control. Health issues should be especially promoted in kindergartens and at urban-rural junctions. [ABSTRACT FROM AUTHOR]

Background: Norovirus (NoV) is a leading cause of sporadic cases and outbreaks of acute gastroenteritis (AGE). Increased NoV activity was observed in Beijing, China during winter 2014-2015; therefore, we examined the epidemiological patterns and genetic characteristics of NoV in the sporadic cases and outbreaks.Methods: The weekly number of infectious diarrhea cases reported by all hospitals in Beijing was analyzed through the China information system for disease control and prevention. Fecal specimens were collected from the outbreaks and outpatients with AGE, and GI and GII NoVs were detected using real time reverse transcription polymerase chain reaction. The partial capsid genes and RNA-dependent RNA polymerase (RdRp) genes of NoV were both amplified and sequenced, and genotyping and phylogenetic analyses were performed.Results: Between December 2014 and March 2015, the number of infectious diarrhea cases in Beijing (10,626 cases) increased by 35.6% over that of the previous year (7835 cases), and the detection rate of NoV (29.8%, 191/640) among outpatients with AGE was significantly higher than in the previous year (12.9%, 79/613) (χ(2) = 53.252, P < 0.001). Between November 2014 and March 2015, 35 outbreaks of AGE were reported in Beijing, and NoVs were detected in 33 outbreaks, all of which belonged to the GII genogroup. NoVs were sequenced and genotyped in 22 outbreaks, among which 20 were caused by a novel GII.17 strain. Among outpatients with AGE, this novel GII.17 strain was first detected in an outpatient in August 2014, and it replaced GII.4 Sydney_2012 as the predominant variant between December 2014 and March 2015. A phylogenetic analysis of the capsid genes and RdRp genes revealed that this novel GII.17 strain was distinct from previously identified GII variants, and it was recently designated as GII.P17_GII.17. This variant was further clustered into two sub-groups, named GII.17_2012 and GII.17_2014. During winter 2014-2015, GII.17_2014 caused the majority of AGE outbreaks in China and Japan.Conclusions: During winter 2014-2015, a novel NoV GII.17 variant replaced the GII.4 variant Sydney 2012 as the predominant strain in Beijing, China and caused increased NoV activity. [ABSTRACT FROM AUTHOR]

Objective: To investigate the epidemiological and clinical characteristics of norovirus infection on diarrhea patients from the enteric clinics in Beijing., Methods: From April 2013 to March 2014, 1 892 fecal specimens and related epidemiological information were collected among diarrhea patients visiting the enteric clinics in Beijing. Norovirus was detected by real time RT-PCR, and data was analyzed under the descriptive epidemiological method., Results: A total of 269 positive cases were found among 1 892 diarrhea patients, with a positive rate as 14.2%. Norovirus caused diarrhea mainly occurred in seasons with lower temperature. Higher positive rates of norovirus were found in northwest mountainous area. Norovirus diarrhea was more commonly seen in children between 6 month and 5 years old, with differences between the two groups statistically significant (P = 0.006). Compared with other occupation, a higher infection rate was identified in children, with differences between the two groups statistically significant (P = 0.025). Nausea and vomiting appeared more common in diarrhea patients with norovirus infection, with differences between the two groups statistically significant (P < 0.05)., Conclusion: Norovirus was an important pathogen which causing diarrhea in patients visiting the enteric clinics in Beijing. The virus was seen more in patients aged between 6 months and 5 years old. Nausea and vomiting were the common symptoms seen in patients with norovirus diarrhea.

Objective: To understand the distribution of virulence gene and the epidemiological characteristics of diarrheagenic Escherichia(E.) coli (DEC) from diarrheal patients in Beijing., Methods: Stool specimens from diarrheal patients were cultured which were collected from the hospitals under sentinel surveillance program, during 2012-2013. DNA was examined by real-time PCR., Results: 253 out of 6 370 specimens were positive for DEC detection with the rate as 4.0%. A total number of 262 DEC strains were isolated. Two different pathotypes of DEC strains with mixed infection, were isolated from 9 specimens. Different pathotypes would show the following profiles: 42.8% for enteropathogenic E. coli (EPEC) including 42.0% atypical and 0.8% typical; 38.9% for enterotoxigenic E. coli (ETEC) including 24.8% st positive, 9.9% lt positive and 4.2% st and lt both positive;15.3% for enteroaggregative E. coli(EAEC);2.7% for enteroinvasive E. coli (EIEC); one strain STEC with serotype O26:K60. ETEC had obvious characteristics on age. All kinds of DEC were isolated throughout the year with seasonal fluctuation., Conclusion: DEC isolates from diarrheal patients in Beijing were dominated by EPEC and ETEC, with atypical ones accounted for the majority of EPEC. One specimen was found under mixed infection. Pathotypes DEC were found to have different age and seasonal distributions.