Xiaorong Peng

A Decline in HIV and Syphilis Epidemics in Chinese Female Sex Workers (2000-2011): A Systematic Review and Meta-Analysis

Background Female sex workers (FSWs) play an important role in transmitting HIV and syphilis from high-risk groups to the general population. However, the trends in HIV and syphilis epidemics in Chinese FSWs in the period after 2000 are unclear to date. Methods The Preferred Reporting Items for Systematic Reviews and Meta-Analyses Statement was followed. Seven databases were searched for published peer-reviewed articles. The incidence of HIV and syphilis in FSWs in different time periods, provinces and workplaces in China were separately pooled by meta-analysis. Correlation analysis was conducted between HIV and syphilis incidence and study time, respectively. Results After 1,662 articles were screened, 190 published papers were included in the final analysis. Estimated HIV prevalence was 0.284% (95% CI: 0.080–0.488%) in the period 2000–2002, 0.211% (95% CI: 0.149–0.273%) in 2003–2005, 0.242% (95% CI: 0.190–0.294%) in 2006–2008 and 0.041% (95% CI: 0.024–0.058%) in 2009–2011. The corresponding syphilis prevalence was 9.669% (95% CI: 7.810–11.529%), 4.970% (95% CI: 4.384–5.556%), 4.404% (95% CI: 4.032–4.775%) and 3.169% (95% CI: 2.738–3.600%), respectively. Spearman rank correlation coefficients were −0.165 (p = 0.002) between HIV prevalence and study time, and −0.209 (p = 0.000) between syphilis prevalence and study time. The combined HIV prevalence was 0.318% (95% CI: 0.156–0.479%) in medium and high-tier workplaces and 0.393% (95% CI: 0.176–0.610%) in low-tier workplaces. The corresponding syphilis prevalence was 3.216% (95% CI: 2.192–4.240%) and 13.817% (95% CI: 10.589–17.044%), respectively. Conclusions Our data suggested a decline in HIV and syphilis epidemics in FSWs in China on a national level during the study period (2000–2011). FSWs in low-tier workplaces should be given more attention in the future to ensure they are included in prevention programs for HIV and sexually transmitted diseases.

Multiple amino acid substitutions involved in the adaptation of avian-origin influenza A (H10N7) virus in mice.

AbstractTo identify substitutions that are possibly associated with the adaptation of avian-origin H10N7 virus to mammals, adaptation of the H10N7 virus in mouse lung was carried out by serial lung-to-lung passage. Genomic analysis of the mouse-adapted virus revealed amino acid changes in the PB2 (E627K), PA (T97I), and HA (G409E) proteins, and this virus was more virulent in mice than the wild-type virus. Our results suggest that these substitutions are involved in the enhancement of the replication efficiency of avian-origin H10N7 virus, resulting in severe disease in mice. Continued poultry surveillance of these substitutions in H10N7 viruses is required.

Amino acid substitutions occurring during adaptation of an emergent H5N6 avian influenza virus to mammals.

Avian influenza viruses (AIVs) are known to cross species barriers, and emergent highly pathogenic H5N6 AIVs pose a serious threat to human health and the poultry industry. Here, we serially passaged an H5N6 virus 10 times in BALB/c mice. The pathogenicity of the wild-type 6D2 (WT-6D2) and mammal-adapted 6D2 strain (MA-6D2) were compared. The viral titer in multiple organs and the death rate for MA-6D2 were significantly higher than for WT-6D2. We provide evidence that the mutations HA A150V, NA R143K and G147E, PB2 E627K, and PA A343T may be important for adaptation of H5N6 AIVs to mammals.

Isolation and characterization of a novel H10N2 avian influenza virus from a domestic duck in Eastern China.

During the surveillance for avian influenza viruses (AIVs) in live poultry markets (LPMs) in Eastern China, in 2013, an H10N2 AIV was isolated from a domestic duck. Phylogenetic analysis showed that this strain received its genes from H10, H1 and H7 AIVs of wild birds in China. The virulence of this strain was examined in chickens and mice, and was found to be low pathogenic in chickens but demonstrated moderate pathogenicity in mice. These results suggest that active surveillance of AIVs in LPMs should be used in an early warning system for avian influenza outbreaks.

Amino acid substitutions involved in the adaptation of a novel highly pathogenic H5N2 avian influenza virus in mice.

BackgroundH5N2 avian influenza viruses (AIVs) can infect individuals that are in frequent contact with infected birds. In 2013, we isolated a novel reassortant highly pathogenic H5N2 AIV strain [A/duck/Zhejiang/6DK19/2013(H5N2) (6DK19)] from a duck in Eastern China. This study was undertaken to understand the adaptive processes that led enhanced replication and increased virulence of 6DK19 in mammals. 6DK19 was adapted to mice using serial lung-to-lung passages (10 passages total). The virulence of the wild-type virus (WT-6DK19) and mouse-adapted virus (MA-6DK19) was determined in mice. The whole-genome sequences of MA-6DK19 and WT-6DK19 were compared to determine amino acid differences.FindingsAmino acid changes were identified in the MA-DK19 PB2 (E627K), PB1 (I181T), HA (A150S), NS1 (seven amino acid extension “WRNKVAD” at the C-terminal), and NS2 (E69G) proteins. Survival and histology analyses demonstrated that MA-6DK19 was more virulent in mice than WT-6DK19.ConclusionOur results suggest that these substitutions are involved in the enhanced replication efficiency and virulence of H5N2 AIVs in mammals. Continuing surveillance for H5N2 viruses in poultry that are carrying these mutations is required.

Characterization of Novel Reassortant Influenza A (H5N2) Viruses Isolated from Poultry in Eastern China, 2015

Recently, novel variants of H5 highly pathogenic avian influenza viruses (AIVs) have been frequently isolated from poultry and wild birds in Asia, Europe and North America. Live poultry markets (LPMs) play an important role in the dissemination of influenza viruses. Four H5N2 AIVs were isolated from poultry during surveillance of AIVs in LPMs in Eastern China, in 2015. Whole-genome sequencing, combined with phylogenetic and antigenic analyses were performed to characterize these viruses. These H5N2 viruses had undergone extensive reassortment resulting in two genetic groups of viruses in poultry. These viruses exhibited slightly pathogenicity in mice, and replicated without prior adaptation. The continued circulation of these novel H5N2 viruses may represent a threat to human health.

Molecular characterization of a novel reassortant H7N6 subtype avian influenza virus from poultry in Eastern China, in 2016.

During the surveillance for avian influenza viruses (AIVs) in live poultry markets in Eastern China, in 2016, a novel reassortant H7N6 AIV was isolated from a chicken. Phylogenetic analysis showed that this strain received its genes from H9N2, H7N9 and H5N6 AIVs infecting poultry in China. This strain showed moderate pathogenicity in mice and was able to replicate in mice without prior adaptation. Considering that this novel reassorted H7N6 virus was isolated from poultry in this study, it is possible that chickens play an important role in the generation of novel reassorted H7N6 AIVs.

Genetic and molecular characterization of a novel reassortant H2N8 subtype avian influenza virus isolated from a domestic duck in Zhejiang Province in China.

The circulation of the H2 subtype influenza viruses in domestic animals increases the risk of human exposure to these viruses. An H2N8 avian influenza virus (AIV) was isolated from a domestic duck during AIV surveillance of poultry in live poultry markets (LPMs) in Zhejiang Province, Eastern China, in 2013. The phylogenetic trees suggested that this strain is a novel reassortant virus derived from multiple AIV subtypes from aquatic birds and poultry in Eastern Asia. Although this reassortant strain exhibited low pathogenicity in mice, it was able to replicate in the lungs of the mice without prior adaptation. Continued surveillance of domestic ducks in LPMs is required for early detection of AIV outbreaks in poultry and humans.

Molecular characterization of a novel reassortant H1N2 influenza virus containing genes from the 2009 pandemic human H1N1 virus in swine from eastern China

Pandemic outbreaks of H1N1 swine influenza virus have been reported since 2009. Reassortant H1N2 viruses that contain genes from the pandemic H1N1 virus have been isolated in Italy and the United States. However, there is limited information regarding the molecular characteristics of reassortant H1N2 swine influenza viruses in eastern China. Active influenza surveillance programs in Zhejiang Province identified a novel H1N2 influenza virus isolated from pigs displaying clinical signs of influenza virus infection. Whole-genome sequencing was performed and this strain was compared with other influenza viruses available in GenBank. Phylogenetic analysis suggested that the novel strain contained genes from the 2009 pandemic human H1N1 and swine H3N2 viruses. BALB/c mice were infected with the isolated virus to assess its virulence in mice. While the novel H1N2 isolate replicated well in mice, it was found to be less virulent. These results provide additional evidence that swine serve as intermediate hosts or ‘mixing vessels’ for novel influenza viruses. They also emphasize the importance of surveillance in the swine population for use as an early warning system for influenza outbreaks in swine and human populations.

Isolation and molecular characterization of reassortant H11N3 subtype avian influenza viruses isolated from domestic ducks in Zhejiang Province in China

In July 2013, six H11N3 subtype avian influenza viruses (AIVs) were isolated from domestic ducks in Zhejiang Province in Eastern China. These strains were characterized by whole genome sequencing with subsequent phylogenetic analysis and genetic comparison. Phylogenetic analysis of all eight viral genes showed that these strains clustered in the AIV Eurasian lineage, and these strains received their genes from H11, H7, and H1 AIVs in Eastern China. These strains were found to be minimally pathogenic in mice, and were able to replicate in mice without prior adaptation. Continued surveillance is needed considering the important role of domestic ducks in AIV reassortment.