Circulation of reassortant influenza A(H7N9) viruses in poultry and humans, Guangdong Province, China, 2013.

Influenza A(H7N9) virus emerged in eastern China in February 2013 and continues to circulate in this region, but its ecology is poorly understood. In April 2013, the Guangdong Provincial Center for Disease Control and Prevention (CDC) implemented environmental and human syndromic surveillance for the virus. Environmental samples from poultry markets in 21 city CDCs (n=8,942) and respiratory samples from persons with influenza-like illness or pneumonia (n=32,342) were tested; viruses isolated from 6 environmental samples and 16 patients were sequenced. Sequence analysis showed co-circulation of 4 influenza A(H7N9) virus strains that evolved by reassortment with avian influenza A(H9N2) viruses circulating in this region. In addition, an increase in human cases starting in late 2013 coincided with an increase in influenza A H7 virus isolates detected by environmental surveillance. Co-circulation of multiple avian influenza viruses that can infect humans highlights the need for increased surveillance of poultry and potential environmental sources.This study was financially supported by 12th five-year-major-projects of China’s Ministry of Public Health. Grant No: 2012zx10004-213 and by the PREDICT Surveillance Animal Human Interface Project of GVF. Grant No: Gvf: 06-09-057-02.This is the accepted version. It'll be replaced with the final pdf when it's available

Effect of live poultry market interventions on influenza A(H7N9) virus, Guangdong, China

Since March 2013, three waves of human infection with avian influenza A(H7N9) virus have been detected in China. To investigate virus transmission within and across epidemic waves, we used surveillance data and whole-genome analysis of viruses sampled in Guangdong during 2013–2015. We observed a geographic shift of human A(H7N9) infections from the second to the third waves. Live poultry market interventions were undertaken in epicenter cities; however, spatial phylogenetic analysis indicated that the third-wave outbreaks in central Guangdong most likely resulted from local virus persistence rather than introduction from elsewhere. Although the number of clinical cases in humans declined by 35% from the second to the third waves, the genetic diversity of third-wave viruses in Guangdong increased. Our results highlight the epidemic risk to a region reporting comparatively few A(H7N9) cases. Moreover, our results suggest that live-poultry market interventions cannot completely halt A(H7N9) virus persistence and dissemination

Production of reactive oxygen species and its role in mediating the abiotic transformation of organic carbon in sandy soil under vegetation restoration

Abstract The significant impact of vegetation restoration on the turnover of organic carbon (OC) is mainly attributed to biological processes. However, the contribution of abiotic processes associated with reactive oxygen species (ROS) during vegetation restoration has remained largely overlooked. Therefore, we systematically explored ROS distribution and production mechanisms in sandy soil and their corresponding effects on OC oxidation through field monitoring and incubation experiments. The cumulative concentrations of hydroxyl radicals (•OH) produced within 24 h varied in different soils undergoing vegetation restoration, ranging from 2.36 to 22.05 μmol kg‒1, which were derived from the Fenton-like reaction of hydrogen peroxide (H2O2) and biotic-induced Fe(II). In addition, during the oxidation of reductive SOC, H2O2 can be formed and react with Fe(II) to generate •OH. Further, •OH significantly induced the abiotic transformation of OC, accounting for 15.93%‒25.80% of carbon dioxide (CO2) efflux. Specifically, 1 mol •OH can induce the production of 0.01–0.02 mol CO2 for particulate organic carbon (POC) and 0.03‒0.23 mol CO2 for mineral-associated organic carbon (MOC), as demonstrated by chemical quenching and sterilisation experiments. This indicated that MOC was more sensitive to •OH attacks. Collectively, our findings provide insights into the accumulation of ROS in sandy soils during vegetation restoration, with •OH playing a key role in SOC oxidation, as well as the patterns of SOC turnover and its response to changes in the soil environment. Graphical Abstrac

Self-driven directional dehydration enabled eco-friendly manufacture of chrome-free leather

Abstract Manufacture of eco-friendly chrome-free leather is of great significance for realizing sustainable development of leather industry. Conventional tanning theory believes that it is impossible to convert raw hide to leather without the utilization of cross-linking agent (e.g., chrome salts) among collagen fibers in raw hide. Here, we developed a brand-new leather manufacture strategy that relied on the composite dehydration media enabled self-driven directional dehydration mechanism to accomplish chrome-free leather manufacture for the first time, rather than followed the classic cross-linking mechanism that has been obeyed for more than one century in leather industry. We demonstrated that the essence of leather making is to regulate the water content in raw hide rather than to form cross-linkage among collagen fibers. The composite dehydration media comprised of anhydrous ethanol and molecular sieves (3A activated zeolite powder) successfully guaranteed continuous self-driven directional dehydration of raw hide by establishing stable water concentration gradient between raw hide and ethanol, which significantly increased the dispersity of collagen fibers in raw hide (with the water content reduced from 56.07% to 5.20%), thus obtaining chrome-free leather that is more ecological than chrome-tanned leather due to the elimination of any tanning agent. The as-prepared chrome-free leather exhibited outstanding tear force (174.86 N), tensile strength (24.56 N mm−2), elongation at break (53.28%) and dry-thermal stability, superior to chrome-tanned leather. Notably, the used composite dehydration media was recyclable for chrome-free leather manufacture, therefore facilitating an environmentally benign leather manufacture process. Our investigations are expected to open up a new conceptual leather making strategy that is applicable for realizing substantial manufacture of eco-friendly leather. Graphical abstrac

Temporal trends of influenza A (H1N1) virus seroprevalence following 2009 pandemic wave in Guangdong, China: three cross-sectional serology surveys.

BackgroundTo evaluate the temporal trends of seroprevalence to pH1N1 among the Guangdong population following 2009 H1N1 pandemic wave, we conducted three cross-sectional serology surveys in 2010.Methodology/principal findingsThree surveys were carried out consecutively in 2010 from January 8 to January 24, from March 15 to April 10 and from August 23 to September 4. Sample populations comprising of 4725, 4727, and 4721 subjects respectively were randomly selected for study in these three surveys. The level of antibodies against pH1N1 was evaluated by hemagglutination inhibition assay. In survey 1, the seroprevalence of pH1N1 among all the subjects is 25.1%, declining to 18.4% in survey 2 and increasing to 21.4% in survey 3. Among vaccinated subjects, the seroprevalence was 49.0%, 53.0%, and 49.4% in the three consecutive surveys, showing no significant differences. In contrast, among non-vaccinated subjects, the seroprevalence declined significantly from 22.8% (survey 1) to 14.3% (survey 2) and subsequently increased to 18.1% (survey 3). The multivariate logistic regression analysis revealed that seroprevalence to pH1N1 in non-vaccinated individuals correlated with the investigated order of the surveys, age, and region (all PConclusions/significanceIn Guangdong, the seroprevalance to pH1N1 decreased initially and then rebounded modestly during the first 9 months following the 2009 pandemic wave. Our results suggest that the prevalence of pH1N1 is still correlated with age and population density during the post-pandemic period. An early end to the free pH1N1 vaccination program might be another important reason for the slight rebound in seroprevalance. Our study findings can help the Guangdong authorities to make evidence-based decisions about a long-term vaccination strategy and boost immunity in specific population groups (such as children and people living in the capital-city) to prevent further transmission in the future

Serologic survey of the pandemic H1N1 2009 virus in Guangdong Province, China: a cross sectional study.

BACKGROUND: Relying on surveillance of clinical cases limits the ability to understand the full impact and severity of an epidemic, which urges a deep insight into the serological evidence of infection and transmission feature of pandemic H1N1 2009 (pH1N1) virus in Guangdong province. METHODS: In this cross-sectional serological survey, serum samples were collected by multi-stage stratified random sampling in Jan 2010. Antibody titers were measured by hemagglutination inhibition (HI) assay. Age-specific and region-specific prevalence were calculated based on the results of HI assay (positive, HI titer≥1:40). RESULTS: A total of 4,319 serum samples had been collected from subjects without vaccination with pH1N1 vaccine. The seroprevalence was 22.82% (985/4,319). By contrast, there was a marked spatial heterogeneity in prevalence. The seroprevalence was 27.3% in large city, 21.4% in medium cities, higher than that of 20.2% in rural areas. The seroprevalence was highest in 11-20 age group (32.8%), however, in those above 60 years of age group, which was 12.6%, lower than other age groups. On the other hand, antibody titers to pH1N1 virus were highest in school children, which were followed by a gradual decrease in adult. However, in the elderly groups from cities, especially from large city, the antibody titer to pH1N1 increased significantly and reached a much higher level. CONCLUSION: Our results showed that the prevalence for pH1N1 was correlated with age and population density. Preexisting antibody may have protected the very old from pH1N1 infection, while original antigenic sin and immunosenescence may have contributed to greater severity once infected. These should be considered when studying the pathogenesis and transmission of influenza virus and formulating strategies on vaccination and treatment

Evolution and Transmission of Respiratory Syncytial Group A (RSV-A) Viruses in Guangdong, China 2008-2015

Respiratory syncytial viruses (RSV) including subgroups A (RSV-A) and B (RSV-B) are an important cause of acute respiratory tract infections worldwide. RSV-A include major epidemic strains. Fundamental questions concerning the evolution, persistence and transmission of RSV-A are critical for disease control and prevention, yet remain unanswered. In this study, we generated 64 complete G gene sequences of RSV-A strains collected between 2008 and 2015 in Guangdong, China. Phylogenetic analysis was undertaken by incorporating 572 publicly available RSV-A sequences. Current data indicate that genotypes GA1, GA4 and GA5 are endemic with limited epidemic activity. In contrast, the GA2 genotype which likely originated in 1980 has spread rapidly and caused epidemics worldwide. By analyzing GA2 genotype sequences across epidemic seasons within Guangdong, we find that RSV-A epidemics in Guangdong are caused by a combination of virus importation and local persistence, although the magnitude of the latter is likely overestimated due to infrequent sampling in other regions. Our results provide new insights into RSV-A evolution and transmission at global and local scales and highlights the rapid and wide spread of genotype GA2 compared to other genotypes. In order to control RSV transmission and outbreak, both local persistence and external introduction should be taken into account when designing optimal strategie

Temporal trends of 2009 H1N1 seroprevalence by influencing factors among the non-vaccinated subjects, Guangdong, 2010.

<p>CI:Confidence Interval;</p>*<p>compared with survey1,P<0.05(by Chi-square);</p>#<p>compared with survey2, P<0.05(by Chi-square);</p

Temporal trends of 2009 H1N1 seroprevalence by demographic characterstics among the vaccinated subjects,Guangdong, 2010.

<p>CI:Confidence Interval;</p>*<p>compared with survey1,P<0.05(by Chi-square);</p>#<p>compared with survey2, P<0.05(by Chi-square);</p