Rotavirus (RV), norovirus (NoV), sapovirus (SaV), human astrovirus (HAstV) and human adenovirus (HAdV) are significant because they are the most common pathogens that cause diarrhea in young children. The aim of this study was to investigate the genetic characteristics and compare the roles of these five viruses in outpatient children with diarrhea in Shanghai. A total of 436 fecal samples were collected from pediatric patients with acute gastroenteritis from January 2010 to December 2011. The selected samples were subjected to reverse transcription PCR (RT-PCR) or PCR to detect and genotype RV, NoV, SaV, HAstV and HAdV. RV (43.3 %, 189/436) was the most prevalent virus, followed by NoV (28.9 %, 126/436), HAdV (7.1 %, 31/436). HAstV (1.8 %, 8/436) and SaV (0.5 %, 2/436). The percentage of multiple infection cases was 14.9 % (65/436), and RV + NoV was the predominant mixed infection. The RV genotype combinations of P[8]G3 (52/189, 27.5 %), P[8]G1 (51/189, 26.9 %) and P[8]G9 (48/189, 25.4 %) occurred most frequently. The predominant NoV genotype was GII.4 (73.0 %, 92/126), and the majority of GII.4 clustered as GII.4-2006b (65.2 %, 60/92). Two of the SaV cases were identified as GI.2 and GII.1. All HAstV-positive samples belonged to HAstV-1. The predominant HAdV type was HAdV-41 (45.2 %, 14/31). This study clearly shows the diversity of the viral causative agents of acute gastroenteritis in outpatient children in Shanghai, which will provide baseline information for future vaccination strategies and development in this area.

Human parechoviruses (HPeVs) are widespread pathogens belonging to the Picornavirus family. The aim of the present study was to assess the prevalence and genetic diversity of HPeV in Shanghai, China, during a HPeV screening program in 2008 and 2009. Of 300 stool samples from children under the age of 5 years with acute diarrhea seen at Children's Hospital, Fudan University, Shanghai, China, 165 (55%) were HPeV-positive. The median age of infected children was 3 months. The prevalence of HPeV was high (57%) in infants up to 2 years old but dropped to 30.4% in children between 2 and 5 years old. The prevalence did not differ by sex. Infections were present throughout the year but peaked in July and August. The most predominant genotype was HPeV1. Of the 139 strains, 4 were found in 9 samples: HPeV4 (n = 4), HPeV5 (n = 1), HPeV6 (n = 1), and HPeV8 (n= 3). This study provided useful data on the epidemiology of HPeV infection by documenting the distribution of genotypes, age of infection, and seasonal patterns in Shanghai, China.

Sporadic HFMD (hand foot and mouth disease, HFMD) cases and outbreaks caused by etiologic agents other than EV71 and CA16 have increased globally. We conducted this study to investigate the prevalence and genetic characteristics of enteroviruses, especially the non-EV71 and non-CA16 enteroviruses, causing HFMD in Shanghai. Clinical specimens were collected from patients with a diagnosis of HFMD. A partial length of VP1 was amplified with RT-PCR and subjected to direct sequencing. Phylogenetic analyses were performed using MEGA 5.0. The ages of the HFMD cases ranged from 3 to 96 months, and the male/female ratio was 1.41. The median hospital stay was 2.96 days. Up to 18.0% of patients had neurologic system complications such as encephalitis, meningoencephalitis or meningitis. Of the 480 samples, 417 were positive for enterovirus (86.9%) with RT-PCR. A total of 13 enterovirus genotypes were identified. The most frequent genotypes were CA6 (31.9%), EV71 (30.6%), CA16 (8.8%) and CA10 (7.5%). Infections with CA6, EV71, CA16 and CA10 were prevalent throughout the years of study, while the proportion of CA6 notably increased from Sep. 2012 to Dec. 2013. Phylogenetic analyses showed that EV71 strains belonged to the C4a subgenogroup and CA16 was identified as B1b subgenogroup. The CA6 strains were assigned to genogroup F, whereas the CA10 strains were assigned to genogroup D. Patients infected with CA6 were typically younger, had a shorter hospital stay and had a lower incidence of neurologic system complications when compared to patients infected with EV71. Our study demonstrates that the enterovirus genotypes causing HFMD were diversified, and there was an increasing prevalence of the non-EV71 and non-CA16 enteroviruses from 2012 to 2013. CA6 was the most predominant pathogen causing HFMD from Sep. 2012 to Dec. 2013, and it often caused relatively mild HFMD symptoms. Most severe HFMD cases were associated with EV71 infection.

BackgroundA rapid expansion of hand, foot, and mouth disease (HFMD) outbreaks has occurred and caused deaths in China in recent years, but little is known about the other etiologic agents except enterovirus 71 (EV71) and coxsackievirus A 16 (CA16). The objective of this study is to determine the genotype compositions of enterovirus causing HFMD in Shanghai and identify any associations between enterovirus types and clinical manifestations.MethodsStool specimens were collected from patients hospitalized for treatment of HFMD, from May 2010 to April 2011. Enterovirus was detected by reverse transcription PCR and directly genotyped by sequencing the PCR products. Phylogenetic analysis was based on the VP1 partial gene.ResultsOf 290 specimens, 277 (95.5%) tested positive for enterovirus. The major genotypes were EV71 (63.8%), CA10 (9.0%), CA6 (8.3%), CA16 (6.9%), CA12 (2.4%), and CA4 (1.4%). The EV71 strains belonged to the C4a subtype and CA16 belonged to the B subtype. CA6 was closely related to strains detected in Japan, Taiwan and China, and CA10, CA12 and CA4 were phylogenetically similar to other strains circulating in China. Mean hospital stays and the prevalence of complications in patients with EV71 infection were higher than those in patients in CA6, CA10 or CA16 infection (P < 0.05 for all comparisons). Children with CA12 infection were the youngest, and most likely have the highest risk of complications when compared to the other non-EV71 infection groups.ConclusionsThis study demonstrated a diversified pathogen compositions attributing to HFMD and clinical symptoms differing in enterovirus genotypes. It deserves our attention as early identification of enterovirus genotypes is important for diagnosis and treatment of HFMD patients.

Human caliciviruses (HuCVs), especially noroviruses, are currently the second leading cause of acute diarrhea in children; however, data are limited in Shanghai and other regions of the world regarding the epidemic difference of HuCV infections between inpatients and outpatients. Fecal samples (n = 1110) were collected from children up to age 5 years with acute diarrhea treated as inpatients or outpatients at Children's Hospital of Fudan University in Shanghai, between 2006 and 2011. Human calicivirus was detected and genotyped using an RT-PCR assay for the RdRp gene. Among inpatients, 206 HuCV-positive samples (30.6 %) were detected as positive for norovirus. The predominant norovirus genotype was GII.4 (75.5 %), followed by GII.12 (22.3 %), GII.7 (1.0 %), and GII.b (1.0 %). Among outpatients, 128 samples (29.4 %) were positive for HuCV. Of these, 126 were positive for norovirus and two were positive for sapovirus. The predominant norovirus genotypes causing infections in outpatients were GII.4 (71.8 %) and GII.b (15.6 %), followed by GII.12 (9.5 %), GII.7 (0.8 %), and GII.2 (0.8 %). The GII.4-2006b variant was the predominant subtype both in inpatients and outpatients. Characteristics of the HuCV epidemic differ between inpatients and outpatients. Continued surveillance is vital to determine the molecular prevalence of HuCV and to develop effective vaccines.