A study of the relationship between #human #infection with #avian #influenza A #H5N6 and environmental avian influenza viruses in #Fujian, #China (BMC Infect Dis., abstract)

[Source: US National Library of Medicine, full page: (LINK). Abstract, edited.]

BMC Infect Dis. 2019 Sep 2;19(1):762. doi: 10.1186/s12879-019-4145-6.

A study of the relationship between human infection with avian influenza a (H5N6) and environmental avian influenza viruses in Fujian, China.

Chen P1, Xie JF1,2, Lin Q2, Zhao L2, Zhang YH2, Chen HB2, Weng YW1,2, Huang Z2, Zheng KC3,4.

Author information: 1 College of Public Health, Fujian Medical University, No. 88, Jiaotong Road, Taijiang District, Fuzhou, 350000, China. 2 Fujian Center for Disease Control and Prevention, Fujian Provincial Key Laboratory of Zoonosis Research, Fuzhou, 350001, China. 3 College of Public Health, Fujian Medical University, No. 88, Jiaotong Road, Taijiang District, Fuzhou, 350000, China. kingdadi9909@126.com. 4 Fujian Center for Disease Control and Prevention, Fujian Provincial Key Laboratory of Zoonosis Research, Fuzhou, 350001, China. kingdadi9909@126.com.

 

Abstract

BACKGROUND:

Avian influenza A (H5N6) virus poses a great threat to the human health since it is capable to cross the species barrier and infect humans. Although human infections are believed to largely originate from poultry contaminations, the transmissibility is unclear and only limited information was available on poultry environment contaminations, especially in Fujian Province.

METHODS:

A total of 4901 environmental samples were collected and tested for Avian Influenza Virus (AIV) from six cities in Fujian Province through the Fujian Influenza Surveillance System from 2013 to 2017. Two patient-related samples were taken from Fujian’s first confirmed H5N6 human case and his backyard chicken feces in 2017. Chi-square test or Fisher’s exact probability test was used to compare the AIV and the viral subtype positive rates among samples from different Surveillance cities, surveillance sites, sample types, and seasons. Phylogenetic tree analysis and molecular analysis were conducted to track the viral transmission route of the human infection and to map out the evolutions of H5N6 in Fujian.

RESULTS:

The overall positive rate of the H5 subtype AIVs was 4.24% (208/4903). There were distinctive differences (p < 0.05) in the positive rates in samples from different cities, sample sites, sample types and seasons. The viruses from the patient and his backyard chicken feces shared high homologies (99.9-100%) in all the eight gene segments. Phylogenetic trees also showed that these two H5N6 viruses were closely related to each other, and were classified into the same genetic clade 2.3.4.4 with another six H5N6 isolates from the environmental samples. The patient’s H5N6 virus carried genes from H6N6, H5N8 and H5N6 viruses originated from different areas. The R294K or N294S substitution was not detected in the neuraminidase (NA). The S31 N substitution in the matrix2 (M2) gene was detected but only in one strain from the environmental samples.

CONCLUSIONS:

The H5 subtype of AIVs has started circulating in the poultry environments in Fujian Province. The patient’s viral strain originated from the chicken feces in his backyard. Genetic reassortment in H5N6 viruses in Fujian Province was indicated. The H5N6 viruses currently circulating in Fujian Province were still commonly sensitive to Oseltamivir and Zanamivir, but the resistance against Amantadine has emerged.

KEYWORDS: Avian influenza a (H5N6) virus; Environmental contamination; Phylogenetic analysis

PMID: 31477028 PMCID: PMC6719373 DOI: 10.1186/s12879-019-4145-6 [Indexed for MEDLINE] Free PMC Article

Keywords: Avian Influenza; H5N6; H5N8; H6N6; Reassortant strain; Human; Poultry; Fujian; China.

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Published by

Giuseppe Michieli

I am an Italian blogger, active since 2005 with main focus on emerging infectious diseases such as avian influenza, SARS, antibiotics resistance, and many other global Health issues. Other fields of interest are: climate change, global warming, geological and biological sciences. My activity consists mainly in collection and analysis of news, public services updates, confronting sources and making decision about what are the 'signals' of an impending crisis (an outbreak, for example). When a signal is detected, I follow traces during the entire course of an event. I started in 2005 my blog ''A TIME'S MEMORY'', now with more than 40,000 posts and 3 millions of web interactions. Subsequently I added an Italian Language blog, then discontinued because of very low traffic and interest. I contributed for seven years to a public forum (FluTrackers.com) in the midst of the Ebola epidemic in West Africa in 2014, I left the site to continue alone my data tracking job.