Molecular epidemiology of human enterovirus associated with aseptic meningitis in Shandong Province, China, 2006-2012.

BACKGROUND: Human enteroviruses (HEVs) are common causes of acute meningitis. However, there is limited information about HEV associated with aseptic meningitis in mainland China because it has not been classified as a notifiable disease. OBJECTIVES: To characterize the HEVs associated with sporadic aseptic meningitis in China and to analyze their genetic features. STUDY DESIGN: Cerebrospinal fluid, throat swab and feces specimens were collected from patients with aseptic meningitis in 5 sentinel hospitals in Shandong Province, China between 2006 and 2012. Virological investigation (viral isolation and molecular identification) and phylogenetic analysis were performed. RESULTS: A total of 437 hospitalized patients were reported, and enteroviruses were detected in the specimens from 84 patients (19.2%) and were identified into 17 serotypes. The nine main serotypes were echovirus (E) 30 (27.4%), EV71 (13.1%), coxsackievirus (CV) B1 (9.5%), CVB3 (7.1%), CVB5 (7.1%), E6 (7.1%), E9 (7.1%), CVA9 (6.0%), and CVA10 (3.6%). Monthly distribution of isolated enteroviruses revealed a major peak in summer-fall season and a small second peak in winter constituted totally by EV71. Sequence analysis on VP1 coding region suggested Shandong strains had great genetic divergence with isolates from other countries. CONCLUSIONS: Multiple serotypes were responsible for enterovirus meningitis in mainland China. Aseptic meningitis caused by EV71 and coxsackie A viruses-the predominant pathogens for the hand, foot, and mouth disease-is currently an important concern in mainland China.

Non-polio enteroviruses from acute flaccid paralysis surveillance in Shandong Province, China, 1988-2013.

Enteroviruses (EVs) are important human pathogens associated with various clinical syndromes. This study represents an overview of non-polio enteroviruses (NPEVs) isolated from acute flaccid paralysis (AFP) surveillance in Shandong Province, China from 1988 to 2013. Altogether 792 and 170 NPEV isolates were isolated from stool specimens of 9263 AFP cases and 1059 contacts, respectively. Complete VP1 sequencing and typing on all 962 isolates revealed 53 NPEV types in which echovirus (E) 6 (7.6%), E14 (7.6%), E11 (7.4%), coxsackievirus (CV) B3 (7.4%), E25 (5.6%), CVB5 (4.9%), E7 (4.5%) and EV-A71 (4.4%) were the eight most commonly reported serotypes. Distinct summer-fall seasonality was observed, with June-October accounting for 79.3% of isolation from AFP cases with known month of specimen collection. Increase of isolation of EV-A71 and CVA--the predominant pathogens for the hand, foot, and mouth disease--was observed in recent years. Sequence analysis on VP1 coding region of EV-A71 and E6 suggested Shandong strains had great genetic divergence with isolates from other countries. The results described in this study provide valuable information on the circulation and emergence of different EV types in the context of limited EV surveillance in China.

Genotypic and phenotypic characterization of HIV-1 CRF01_AE env molecular clones from infections in China.

BACKGROUND: Although a great number of HIV-1 pseudoviruses have been generated for neutralization assays, circulating recombinant forms, such as CRF01_AE, are not included. Given the increasing prevalence of CRF01_AE, the establishment of a pool of CRF01_AE env isolates for the evaluation of potential HIV vaccines is needed. MATERIALS AND METHODS: Full-length env genes were cloned from HIV-1 CRF01_AE-infected plasma samples collected in China and used to establish Env-pseudotyped viruses. The neutralization phenotypes of the pseudoviruses were characterized by testing against broadly neutralizing monoclonal antibodies, coreceptor antagonists, and 42 plasma samples that include 3 main prevalent HIV-1 subtypes in China. RESULTS: Thirty-four genetically distinct CRF01_AE env genes were cloned and used to generate pseudotyped viruses. Of the 34 pseudoviruses, 32 used CCR5 as a coreceptor and 2 used CXCR4. The majority of pseudoviruses were resistant to the neutralizing antibodies IgG1b12 and 2G12 and susceptible to 2F5 and 4E10. There was significant variation of the neutralization susceptibility of pseudoviruses against 42 HIV-1-positive plasma samples. Based on their overall neutralization susceptibilities, the 34 CRF01_AE pseudoviruses were classified into 3 tiers: high, medium, and low. CONCLUSION: The CRF01_AE pseudovirus isolates should be included in the panel of pseudoviruses used to assess vaccine-elicited neutralizing antibodies.