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1.
BMC Infect Dis ; 24(1): 585, 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38867171

RESUMO

BACKGROUND: We investigated the presence of Chlamydia psittaci in poultry and the environment in live poultry wholesale markets in Changsha during 2021-2022 and conducted a phylogenetic analysis to understand its distribution in this market. METHODS: In total, 483 samples were analyzed using real-time polymerase chain reaction and 17 C. psittaci-positive samples using high-throughput sequencing, BLAST similarity, and phylogenetic analysis. RESULTS: Twenty-two out of 483 poultry and environmental samples were positive for C. psittaci (overall positivity rate: 4.55%) with no difference in positivity rates over 12 months. Chlamydia psittaci was detected at 11 sampling points (overall positivity rate: 27.5%), including chicken, duck, and pigeon/chicken/duck/goose shops, with pigeon shops having the highest positivity rate (46.67%). The highest positivity rates were found in sewage (12.5%), poultry fecal (7.43%), cage swab (6.59%), avian pharyngeal/cloacal swab (3.33%), and air (2.29%) samples. The ompA sequences were identified in two strains of C. psittaci, which were determined to bear genotype B using phylogenetic analysis. Thus, during monitoring, C. psittaci genotype B was detected in the poultry and environmental samples from the poultry wholesale market in Changsha. CONCLUSIONS: To address the potential zoonotic threat, C. psittaci monitoring programs in live poultry markets should be enhanced.


Assuntos
Chlamydophila psittaci , Filogenia , Doenças das Aves Domésticas , Aves Domésticas , Psitacose , Animais , Chlamydophila psittaci/genética , Chlamydophila psittaci/isolamento & purificação , Chlamydophila psittaci/classificação , China/epidemiologia , Psitacose/microbiologia , Psitacose/veterinária , Psitacose/epidemiologia , Aves Domésticas/microbiologia , Doenças das Aves Domésticas/microbiologia , Doenças das Aves Domésticas/epidemiologia , Galinhas/microbiologia , Patos/microbiologia , Fezes/microbiologia , Reação em Cadeia da Polimerase em Tempo Real
2.
Food Environ Virol ; 14(1): 30-39, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34997459

RESUMO

In routine surveillance for avian influenza viruses (AIVs) in the environments of live poultry markets (LPMs), certain samples were positive for AIVs type A while negative for subtypes (e.g., H5, H7, and H9). However, little attention has been paid to these unsubtyped AIVs samples. To reveal the dynamic distribution and molecular characteristics of AIVs, especially the unsubtyped AIVs, we reported and analyzed 1969 samples collected from the water environments of LPMs in Changsha, China, from January 2014 to November 2018. Our results revealed that 1504 (76.38%) samples were positive for AIV type A. Of these samples, the predominant hemagglutinin (HA) subtype was H9, followed by H5 and H7 (P < 0.05). The positive rate of H5 subtype in water environmental samples exhibited seasonality, which reached a peak in each winter-spring season from January 2014 to March 2017. The positive rates of AIVs (including type A, subtype H9, and mixed subtype H5/H7/H9) in non-central-city regions were higher than that in the central-city regions (P < 0.05). Notably, 161 unsubtyped AIVs samples were detected during the routine surveillance. However, subtyping with the commercial kit further identified eight different HA and seven different neuraminidase subtypes. Analyses unraveled that further subtyped AIVs H1, H6, and H11 had only one basic amino acid (R or K) at the cleavage site and residues Q226 and G228 at the receptor-binding associated sites. Overall, in addition to H5, H7, and H9 subtypes, we should also pay attention to unsubtyped AIVs samples during the routine surveillance for AIVs in the environments of LPMs.


Assuntos
Vírus da Influenza A , Influenza Aviária , Animais , China/epidemiologia , Vírus da Influenza A/genética , Aves Domésticas , Água
3.
Lancet Microbe ; 3(11): e824-e834, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36115379

RESUMO

BACKGROUND: The H3N8 avian influenza virus (AIV) has been circulating in wild birds, with occasional interspecies transmission to mammals. The first human infection of H3N8 subtype occurred in Henan Province, China, in April, 2022. We aimed to investigate clinical, epidemiological, and virological data related to a second case identified soon afterwards in Hunan Province, China. METHODS: We analysed clinical, epidemiological, and virological data for a 5-year-old boy diagnosed with H3N8 AIV infection in May, 2022, during influenza-like illness surveillance in Changsha City, Hunan Province, China. H3N8 virus strains from chicken flocks from January, 2021, to April, 2022, were retrospectively investigated in China. The genomes of the viruses were sequenced for phylogenetic analysis of all the eight gene segments. We evaluated the receptor-binding properties of the H3N8 viruses by using a solid-phase binding assay. We used sequence alignment and homology-modelling methods to study the effect of specific mutations on the human receptor-binding properties. We also conducted serological surveillance to detect the H3N8 infections among poultry workers in the two provinces with H3N8 cases. FINDINGS: The clinical symptoms of the patient were mild, including fever, sore throat, chills, and a runny nose. The patient's fever subsided on the same day of hospitalisation, and these symptoms disappeared 7 days later, presenting mild influenza symptoms, with no pneumonia. An H3N8 virus was isolated from the patient's throat swab specimen. The novel H3N8 virus causing human infection was first detected in a chicken farm in Guangdong Province in December, 2021, and subsequently emerged in several provinces. Sequence analyses revealed the novel H3N8 AIVs originated from multiple reassortment events. The haemagglutinin gene could have originated from H3Ny AIVs of duck origin. The neuraminidase gene belongs to North American lineage, and might have originated in Alaska (USA) and been transferred by migratory birds along the east Asian flyway. The six internal genes had originated from G57 genotype H9N2 AIVs that were endemic in chicken flocks. Reassortment events might have occurred in domestic ducks or chickens in the Pearl River Delta area in southern China. The novel H3N8 viruses possess the ability to bind to both avian-type and human-type sialic acid receptors, which pose a threat to human health. No poultry worker in our study was positive for antibodies against the H3N8 virus. INTERPRETATION: The novel H3N8 virus that caused human infection had originated from chickens, a typical spillover. The virus is a triple reassortment strain with the Eurasian avian H3 gene, North American avian N8 gene, and dynamic internal genes of the H9N2 viruses. The virus already possesses binding ability to human-type receptors, though the risk of the H3N8 virus infection in humans was low, and the cases are rare and sporadic at present. Considering the pandemic potential, comprehensive surveillance of the H3N8 virus in poultry flocks and the environment is imperative, and poultry-to-human transmission should be closely monitored. FUNDING: National Natural Science Foundation of China, National Key Research and Development Program of China, Strategic Priority Research Program of the Chinese Academy of Sciences, Hunan Provincial Innovative Construction Special Fund: Emergency response to COVID-19 outbreak, Scientific Research Fund of Hunan Provincial Health Department, and the Hunan Provincial Health Commission Foundation.


Assuntos
COVID-19 , Vírus da Influenza A Subtipo H3N8 , Vírus da Influenza A Subtipo H9N2 , Influenza Aviária , Influenza Humana , Humanos , Animais , Pré-Escolar , Influenza Aviária/epidemiologia , Vírus da Influenza A Subtipo H3N8/genética , Influenza Humana/epidemiologia , Filogenia , Estudos Retrospectivos , Galinhas , Aves Domésticas , Patos , Mamíferos
4.
Artigo em Zh | MEDLINE | ID: mdl-24358747

RESUMO

OBJECTIVE: To understand the changes of schistosomiasis endemic situation and water body security in the Changsha City section of the Xiangjiang River. METHODS: The prevention and control measures of schistosomiasis, the status of Oncomelania hupensis snails in the marshlands, and the schistosome infection rates of residents on the both sides of the river and boat fishermen were investigated from 2003 to 2012. The schistosome infectivity of the water body was investigate by the method of sentry mice. RESULTS: The snail area decreased from 471 hm(2) in 2003 to 28.81 hm(2) in 2012 with the decline rate of 93.88%. Through the environmental modification, no living snails were found in 9 marshlands among the 11 marshlands, and the density of snails was below 0.006/0.1 m(2) in the other 2 marshlands, but no infected snails were found for 7 years. The original snail habitats of Juzhou scenic area were completely modified and no living snails were found from 2008. In the area, no domestic animals were pastured and the schistosome infectivity of the water body was negative with the sentry mouse method for 10 years. In 2003, the schistosome infection rate was 3.63% in the residents, but no new infections were found in original residents after 2010. CONCLUSION: The endemic situation of schistosomiasis of the Changsha City section of the Xiangjiang River has reached the standards of schistosomiasis transmission controlled and the water body of Juzhou scenic area is safe.


Assuntos
Reservatórios de Doenças/parasitologia , Rios/parasitologia , Esquistossomose/epidemiologia , Caramujos/parasitologia , Adolescente , Adulto , Idoso , Animais , Criança , China/epidemiologia , Feminino , Humanos , Masculino , Camundongos , Pessoa de Meia-Idade , Schistosoma/isolamento & purificação , Schistosoma/fisiologia , Esquistossomose/parasitologia , Caramujos/crescimento & desenvolvimento , Adulto Jovem
5.
Biotechnol Adv ; 27(5): 578-82, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19397989

RESUMO

We investigated the kinetics of hot liquid water (HLW) hydrolysis over a 60-min period using a self-designed setup. The reaction was performed within the range 160-220 degrees C, under reaction conditions of 4.0 MPa, a 1:20 solid:liquid ratio (g/mL), at 500 rpm stirring speed. Xylan was chosen as a model compound for hemicelluloses, and two kinds of agricultural wastes-rice straw and palm shell-were used as typical feedstocks representative of herbaceous and woody biomasses, respectively. The hydrolysis reactions for the three kinds of materials followed a first-order sequential kinetic model, and the hydrolysis activation energies were 65.58 kJ/mol for xylan, 68.76 kJ/mol for rice straw, and 95.19 kJ/mol for palm shell. The activation energies of sugar degradation were 147.21 kJ/mol for xylan, 47.08 kJ/mol for rice straw and 79.74 kJ/mol for palm shell. These differences may be due to differences in the composition and construction of the three kinds of materials. In order to reduce the decomposition of sugars, the hydrolysis time of biomasses such as rice straw and palm shell should be strictly controlled.


Assuntos
Biomassa , Celulose/química , Eliminação de Resíduos/métodos , Xilanos/química , Agricultura , Arecaceae , Desenho de Equipamento , Fagus , Temperatura Alta , Hidrólise , Cinética , Análise dos Mínimos Quadrados , Oryza , Termodinâmica , Água/química
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