Search

Reassortment can introduce one or more gene segments of influenza A viruses (IAVs) into another, resulting in novel subtypes. Since 2013, a new outbreak of human highly pathogenic avian influenza has emerged in the Yangtze River Delta (YRD) and South-Central regions of China. In this study, using Anhui province as an example, we discuss the possible impact of H7N9 IAVs on future influenza epidemics through a series of gene reassortment events. Sixty-one human H7N9 isolates were obtained from five outbreaks in Anhui province from 2013-2019. Bioinformatics analyses revealed that all of them were characterized by low pathogenicity and high human or mammalian tropism and have introduced novel avian influenza A virus (AIV) subtypes such as H7N2, H7N6, H9N9, H5N6, H6N6, and H10N6 through gene reassortment. In reassortment events, Anhui isolates may donate one or more segments of HA, NA, and the six internal protein-coding genes for the novel subtype AIVs. Our study revealed that H7N9, H9N2, and H5N1 can serve as stable and persistent gene pools for AIVs in the YRD and South-Central regions of China. Novel AIV subtypes might be generated continuously by reassortment. These AIVs may have obtained human-type receptor-binding abilities from their donors and prefer binding to them, which can cause human epidemics through accidental spillover infections. Facing the continual threat of emerging avian influenza, constant monitoring of AIVs should be conducted closely for agricultural and public health. This article is protected by copyright. All rights reserved.

Background: The genome of SARS-CoV-2 has shown considerable variation during its spreading. Monitoring variations in the virus genome to understand the evolution and spread of the virus is extremely important. Methods: Seven SARS-CoV-2 strains (BB127, BB183, HB030, MAS525, HF3028, FY1494, and SZ005) circulating in Anhui Province, China were isolated and sequenced for evolutionary analysis. Five strains were further cultured in vitro and were subjected to viral growth assay, TCID50 assay, and detection of spike protein expression. Next generation sequence (NGS) analysis were applied to investigate the mutation frequencies throughout the whole genome at different time gradients in vitro. Findings: Our observations revealed that in vitro cultured SARS-CoV-2 virus had much higher mutation frequency (up to ~20 times) than that in infected patients, and the mutation in nonstructural protein 14 (nsp14) might increase the genomic mutation frequency. Different strains had various amount of spike protein which may positively correlated with the virus replication capacity but may be influenced by other viral factors. Interpretation: Our study suggested that SARS-CoV-2 has the potential to diversify under favorable conditions. Monitoring viral mutations is not only helpful for better understanding of virus evolution and virulence change, but also the key to prevent virus transmission and disease progression. SARS-CoV-2 genomic variation analysis may also provide potential ideas for more efficient vaccine development and clinical treatment. Funding: This work is funded by Special Project for Emergency Scientific and Technological Research on New Coronavirus Infection (YG, No. YD9110002001), Emergency Research Project of Novel Coronavirus Infection of Anhui Province (Grant numbers 202004a07020002; 202004a07020004), Postdoctoral Research Foundation of China (2020M670084ZX) and the Fundamental Research Funds for the Central Universities (WK9110000166; WK9110000167). Declaration of Interests: We declare no competing interests. Ethics Approval Statement: The study was conformed to the principles of the Declaration of Helsinki and approved by the Ethics Committee of the First Affiliated Hospital of USTC..

Hand, foot, and mouth disease (HFMD), which is a frequently reported and concerning disease worldwide, is a severe burden on societies globally, especially in the countries of East and Southeast Asia. Coxsackievirus A16 (CV-A16) is one of the most important causes of HFMD and a severe threat to human health, especially in children under 5 years of age. To investigate the epidemiological characteristics, spread dynamics, recombinant forms (RFs), and other features of CV-A16, we leveraged the continuous surveillance data of CV-A16-related HFMD cases collected over an 18-year period. With the advent of the EV-A71 vaccine since 2016, which targeted the EV-A71-related HFMD cases, EV-A71-related HFMD cases decreased dramatically, whereas the CV-A16-related HFMD cases showed an upward trend from 2017 to October 2019. The CV-A16 strains observed in this study were genetically related and widely distributed in the mainland of China. Our results show that three clusters (B1a–B1c) existed in the mainland of China and that the cluster of B1b dominates the diffusion of CV-A16 in China. We found that eastern China played a decisive role in seeding the diffusion of CV-A16 in China, with a more complex and variant transmission trend. Although EV-A71 vaccine was launched in China in 2016, it did not affect the genetic diversity of CV-A16, and its genetic diversity did not decline, which confirmed the epidemiological surveillance trend of CV-A16. Two discontinuous clusters (2000–13 and 2014–18) were observed in the full-length genome and arranged along the time gradient, which revealed the reason why the relative genetic diversity of CV-A16 increased and experienced more complex fluctuation model after 2014. In addition, the switch from RFs B (RF-B) and RF-C co-circulation to RF-D contributes to the prevalence of B1b cluster in China after 2008. The correlation between genotype and RFs partially explained the current prevalence of B1b. This study provides unprecedented full-length genomic sequences of CV-A16 in China, with a wider geographic distribution and a long-term time scale. The study presents valuable information about CV-A16, aimed at developing effective control strategies, as well as a call for a more robust surveillance system, especially in the Asia-Pacific region.

Background: SARS-CoV-2 has caused a huge outbreak in China and multiple countries since it emerged in Wuhan, China in December, 2019 The virus caused diseases

Due to the similar clinical symptoms of influenza (Flu) and coronavirus disease 2019 (COVID-19), there is a looming infection threat of concurrent Flu viruses and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). In this work, we introduce a customized isothermal amplification integrated lateral flow strip (LFS) that is capable performing duplex reverse transcription-recombinase polymerase amplification (RT-RPA) and colorimetric LFS in a sequential manner. With customized amplification primer sets targeted to SARS-CoV-2 (opening reading frame 1a/b and nucleoprotein genes) and Flu viruses (Flu A and Flu B), the platform allows the rapid and simultaneous visual screening of SARS-CoV-2 and Flu viruses (Flu A and Flu B) without cross reactivity, false positives, and false negatives. Moreover, it maximally eases the detection, reduces the detection time (1 h), and improves the assay performance to detect as low as 10 copies of the viral RNA. Its clinical application is powerfully demonstrated with 100% accuracy for evaluating 15 SARS-CoV-2-positive clinical samples, 10 Flu viruses-positive clinical samples, and 5 negative clinical samples, which were pre-confirmed by standard qRT-PCR. We envision this portable device can meet the increasing need of online monitoring the serious infectious diseases that substantially affects health care systems worldwide.

Objective Viral nucleic acid detection by real-time reverse transcription polymerase chain reaction (qPCR) is the current standard method for diagnosis of SARS-CoV-2 infection. However, due to low viral load in some COVID-19 patients, false negative results from this method have been repeatedly reported. Method In this study, we compared the sensitivity and specificity of digital PCR (dPCR) in simulated samples and clinical samples with qPCR assay through a series of vigorous tests. Results The results showed that dPCR was more sensitive than qPCR especially for samples with low viral load (≤3 copies). In addition, dPCR had similar specificity as qPCR and could effectively distinguish other human coronaviruses and influenza virus from SARS-CoV-2. More importantly, dPCR was more sensitive than qPCR in detecting the virus in the “negative” samples from recurrent COVID-19 patients. Conclusions In summary, dPCR could serve as a powerful complement to the current qPCR method for SARS-CoV-2 detection, especially for the samples with extremely low viral load, such as recurrent COVID-19 patients.

We isolated Rickettsia japonica from a febrile patient in Lu’an City, China, in 2013. Subsequently, we found an R. japonica seroprevalence of 54.8% (494/902) in the rural population of Anhui Province and an R. japonica prevalence in Haemaphysalis longicornis ticks of 0.5% (5/935). R. japonica and its tick vector exist in China.

In this paper, the eco-unburned permeable bricks were prepared by simulating the actual production, using steel slag as aggregates and multi-solid waste as cementitious materials. The flexural strength, water permeability coefficient, leaching toxicity and environmental sustainability of permeable bricks were determined. The prepared permeable bricks with a size of 200*100*50 mm and an average weight of 2.15 kg had a flexural strength of 4.5 MPa and a water permeability coefficient of 10.5 × 10-2 cm/s. The solid waste utilization rate reached as high as 96%. The partial f-CaO in steel slag particles was effectively digested and the remaining content was only 2.11% by controlling the curing conditions properly. The results of leaching toxicity test confirmed that the unburned permeable brick will not cause secondary pollution. Compared with the permeable bricks prepared from original materials, the SUB-RAW index of the eco-unburned permeable bricks reached 0.303, proving that it was beneficial to the environment. Therefore, the steel slag based eco-unburned permeable bricks developed in this paper can be used in industrial scale production and have broad application prospects.

Pilot and industrial scale tests for the preparation of permeable bricks were carried out in a refractory plant. The permeable bricks were firstly prepared using 82 wt% ceramic waste large aggregate by pilot test. The permeability, flexural strength and apparent porosity of the obtained permeable bricks can reach 3.2×10−2 cm/s, 6.8 MPa and 28%, respectively, and the relationships between these properties were studied. Moreover, industrial scale test was performed based on the best conditions of the pilot test, and 100 permeable bricks having a size of 140 mm × 280 mm × 80 mm were successfully produced using 600 kg of raw materials. The produced permeable brick has a high permeability of 3.0×10−2 cm/s, flexural strength of 6.3 MPa, as well as a relatively high apparent porosity of 26%, which exceed Chinese national standard GB/T 25993-2010. It has been found that a large number of through holes are homogeneously distributed within the permeable brick, which ensures the high permeability. Meanwhile, the binders make the aggregates interconnect with each other, guaranteeing sufficient mechanical strength. In addition, the energy consumption for whole producing process of permeable bricks is relatively low, about 1.4 MJ/kg. Hence, it is completely feasible to achieve industrial production of permeable bricks with good performance by using solid waste, which not only contributes to the construction of the sponge city, but also meets the requirements of cleaner production and brings obvious ecological and economic benefits.

As emerging tick born rickettsial diseases caused byA. phagocytophilumandE. chaffeensis, anaplasmosis and ehrlichiosis have become a serious threat to human and animal health throughout the world. In particular, in China, an unusual transmission of nosocomial cases of human granulocytic anaplasmosis occurred in Anhui Province in 2006 and more recent coinfection case ofA. phagocytophilumandE. chaffeensiswas documented in Shandong Province. Although the seroprevalence of human granulocytic anaplasmosis (former human granulocytic ehrlichiosis, HGE) has been documented in several studies, these data existed on local investigations, and also little data was reported on the seroprevalence of human monocytic ehrlichiosis (HME) in China. In this cross-sectional epidemiological study, indirect immunofluorescence antibody assay (IFA) proposed by WHO was used to detectA. phagocytophilumandE. chaffeensisIgG antibodies for 7,322 serum samples from agrarian residents from 9 provinces/cities and 819 urban residents from 2 provinces. Our data showed that farmers were at substantially increased risk of exposure. However, even among urban residents, risk was considerable. Seroprevalence of HGA and HME occurred in diverse regions of the country and tended to be the highest in young adults. Many species of ticks were confirmed carryingA. phagocytophilumorganisms in China while several kinds of domestic animals including dog, goats, sheep, cattle, horse, wild rabbit, and some small wild rodents were proposed to be the reservoir hosts ofA. phagocytophilum. The broad distribution of vector and hosts of theA. phagocytophilumandE. chaffeensis, especially the relationship between the generalized susceptibility of vectors and reservoirs and the severity of the disease’s clinical manifestations and the genetic variation of Chinese HGA isolates in China, is urgently needed to be further investigated.

Human infection associated with a novel reassortant avian influenza H7N9 virus has recently been identified in China. A total of 132 confirmed cases and 39 deaths have been reported. Most patients presented with severe pneumonia and acute respiratory distress syndrome. Although the first epidemic has subsided, the presence of a natural reservoir and the disease severity highlight the need to evaluate its risk on human public health and to understand the possible pathogenesis mechanism. Here we show that the emerging H7N9 avian influenza virus poses a potentially high risk to humans. We discover that the H7N9 virus can bind to both avian-type (α2,3-linked sialic acid) and human-type (α2,6-linked sialic acid) receptors. It can invade epithelial cells in the human lower respiratory tract and type II pneumonocytes in alveoli, and replicated efficiently in ex vivo lung and trachea explant culture and several mammalian cell lines. In acute serum samples of H7N9-infected patients, increased levels of the chemokines and cytokines IP-10, MIG, MIP-1β, MCP-1, IL-6, IL-8 and IFN-α were detected. We note that the human population is naive to the H7N9 virus, and current seasonal vaccination could not provide protection.

To study on the phylogenetic characterization of the VP1 genes of coxsackievirus A16 (CVA16) causing hand-food-mouth disease (HFMD) isolated from Anhui province in 2014. A total of 413 throat swab specimens from HFMD patients were collected during January to November, 2014 for the isolation and identification of enteroviruses using real-time RT-PCR assays. The VP1 regions of CVA16 isolates were amplified using RT-PCR and sequenced. And the phylogenetic tree was constructed among the VP1 regions of those isolates, the different genotypes and sub-genotypes of CVA16 strains. A total of 97 enteroviruses were isolated from 413 samples, the positive rate was 23.49% (97/413), including seventeen CVA16, seventy six HEV71 and four other enteroviruses. The results of the phylogenetic tree showed that 17.CVA16 strains isolated from Anhui in 2014 clustered within B1b evolution branch of B1 genotype. The nucleotide and amino acid sequence identities were 95.30%-100% and 98.70%-100% among the isolates, respectively, but within B1b branch of 17 strains formed several small transmission chains. The nucleotide acid of 17 CVA16 isolates in Anhui province were closed to the strains isolated from Yunnan, Hunan, Guangdong, Tibet and Jiangsu, especially from Hunan in 2013 and from Shenzhen of Guangdong in 2014, the identity were 96.40%-99.70%. The CVA16 strains isolated from Anhui in 2014 were all belong to genetic subtype B1b of B1 genotype was dominant, and among those isolates, several small virus transmission chains had formed with co-circulating and evolution.

This study investigated the remediation of cadmium-polluted soil using a combination of stainless steel slag and ammonium humate. These remedial agents were added to an artificially polluted garden soil to inhabit cadmium toxicity in soil by changing the physical and chemical properties of soil in a pot experiment. The results showed that the co-application of ammonium humate and stainless steel slag significantly decreased the total and available soil cadmium concentrations, with maximum decreases of 16.30% and 58.04%, respectively. The co-application of an adequate dose of these remedial agents can significantly increase soil pH. The soil organic matter and cation exchange capacity, as well as the amount of soil aggregates, were also significantly increased by the addition ammonium humate, but not stainless steel slag.

Objective To investigate the epidemiological status of anaplasmosis among farmers and domestic animals in Guangde County where the unusual nosocomial human to human transmission of human granulocytic anaplasmosis occurred in Anhui province and the index patient in this event lived, as well as Huaiyuan County and Mingguang City in Anhui province. Methods From April to May in 2009, 596 farmers, 132 goats, 12 dogs and 6 cows was collected from Guangde, Mingguang and Huaiyuan counties and the IgG antibodies against A. phagocytophilum in farmers, goats, dogs and cattle was determined using an immunofluorescence assay (IFA). The A. phagocytophilum 16S rRNA gene was amplified from blood samples from domestic animals using nested PCR, and the genetic diversity of the 16S rRNA gene was analysed. Results The percentage of farmers with IgG antibodies against A. phagocytophilum in the 3 survey counties was 33.7%, and the individual percentages for Guangde, Mingguang and Huaiyuan counties were 76.5%, 59.2% and 10.4%, respectively. The total seroprevalence in dogs, goats and cattle was 33.3%, 0.8% and 0%, respectively. The percentage of samples positive for amplification of the 16S rRNA gene of A. phagocytophilum in goats, dogs and cattle was 33.3%, 25.0% and 0%, respectively. Analysis of the genetic diversity of the 16S rRNA gene showed that there were two genotypes of A. phagocytophilum . Group A was endemic in Guangde County, which is located in the southeast of Anhui province, where the nosocomial human granulocytic outbreak of anaplasmosis in 2006 occurred. Group B was located north of Huaiyuan County. Conclusions We concluded the prevalence of A. phagocytophilum among farmers and domestic animals in Anhui province was demonstrated, and diagnosis and differential diagnosis of zoonotic “rickettsial” infections should be emphasized in clinical practice. A systemic ecological survey should be conducted to reduce the public health threat to humans and animals.

Coxsackievirus A16 (CVA16) is responsible for nearly 50% of all the confirmed hand, foot, and mouth disease (HFMD) cases in mainland China, sometimes it could also cause severe complications, and even death. To clarify the genetic characteristics and the epidemic patterns of CVA16 in mainland China, comprehensive bioinfomatics analyses were performed by using 35 CVA16 whole genome sequences from 1998 to 2011, 593 complete CVA16 VP1 sequences from 1981 to 2011, and prototype strains of human enterovirus species A (EV-A). Analysis on complete VP1 sequences revealed that subgenotypes B1a and B1b were prevalent strains and have been co-circulating in many Asian countries since 2000, especially in mainland China for at least 13 years. While the prevalence of subgenotype B1c (totally 20 strains) was much limited, only found in Malaysia from 2005 to 2007 and in France in 2010. Genotype B2 only caused epidemic in Japan and Malaysia from 1981 to 2000. Both subgenotypes B1a and B1b were potential recombinant viruses containing sequences from other EV-A donors in the 5’-untranslated region and P2, P3 non-structural protein encoding regions.