Serologic Evidence of Occupational Exposure to Avian Influenza Viruses at the Wildfowl/Poultry/Human Interface

Ecological interactions between wild aquatic birds and outdoor-housed poultry can enhance spillover events of avian influenza viruses (AIVs) from wild reservoirs to domestic birds, thus increasing the related zoonotic risk to occupationally exposed workers. To assess serological evidence of AIV infection in workers operating in Northern Italy at the wildfowl/poultry interface or directly exposed to wildfowl, serum samples were collected between April 2005 and November 2006 from 57 bird-exposed workers (BEWs) and from 7 unexposed controls (Cs), planning three sample collections from each individual. Concurrently, AIV surveillance of 3587 reared birds identified 4 AIVs belonging to H10N7, H4N6 and H2N2 subtypes while serological analysis by hemagglutination inhibition (HI) assay showed recent infections caused by H1, H2, H4, H6, H10, H11, H12, and H13 subtypes. Human sera were analyzed for specific antibodies against AIVs belonging to antigenic subtypes from H1 to H14 by using HI and virus microneutralization (MN) assays as a screening and a confirmatory test, respectively. Overall, antibodies specific to AIV-H3, AIV-H6, AIV-H8, and AIV-H9 were found in three poultry workers (PWs) and seropositivity to AIV-11, AIV-H13—still detectable in October 2017—in one wildlife professional (WP). Furthermore, seropositivity to AIV-H2, accounting for previous exposure to the “extinct” H2N2 human influenza viruses, was found in both BEWs and Cs groups. These data further emphasize the occupational risk posed by zoonotic AIV strains and show the possible occurrence of long-lived antibody-based immunity following AIV infections in humans.

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Antibodies to Highly Pathogenic A/H5Nx (Clade 2.3.4.4) Influenza Viruses in the Sera of Vietnamese Residents

Pathogens ◽

10.3390/pathogens10040394 ◽

2021 ◽

Vol 10 (4) ◽

pp. 394

Author(s):

Tatyana Ilyicheva ◽

Vasily Marchenko ◽

Olga Pyankova ◽

Anastasia Moiseeva ◽

Tran Thi Nhai ◽

...

Keyword(s):

Influenza Virus ◽

Avian Influenza ◽

Wide Spectrum ◽

Influenza Viruses ◽

Serum Samples ◽

Socialist Republic ◽

Highly Pathogenic ◽

Virus Variant ◽

Human Sera ◽

Hemagglutinin Inhibition

To cause a pandemic, an influenza virus has to overcome two main barriers. First, the virus has to be antigenically new to humans. Second, the virus has to be directly transmitted from humans to humans. Thus, if the avian influenza virus is able to pass the second barrier, it could cause a pandemic, since there is no immunity to avian influenza in the human population. To determine whether the adaptation process is ongoing, analyses of human sera could be conducted in populations inhabiting regions where pandemic virus variant emergence is highly possible. This study aimed to analyze the sera of Vietnamese residents using hemagglutinin inhibition reaction (HI) and microneutralization (MN) with A/H5Nx (clade 2.3.4.4) influenza viruses isolated in Vietnam and the Russian Federation in 2017–2018. In this study, we used sera from 295 residents of the Socialist Republic of Vietnam collected from three groups: 52 samples were collected from households in Nam Dinh province, where poultry deaths have been reported (2017); 96 (2017) and 147 (2018) samples were collected from patients with somatic but not infectious diseases in Hanoi. In all, 65 serum samples were positive for HI, at least to one H5 virus used in the study. In MN, 47 serum samples neutralizing one or two viruses at dilutions of 1/40 or higher were identified. We postulate that the rapidly evolving A/H5Nx (clade 2.3.4.4) influenza virus is possibly gradually adapting to the human host, insofar as healthy individuals have antibodies to a wide spectrum of variants of that subtype.

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Testing human sera for antibodies against avian influenza viruses: Horse RBC hemagglutination inhibition vs. microneutralization assays

Journal of Clinical Virology ◽

10.1016/j.jcv.2008.04.013 ◽

2008 ◽

Vol 43 (1) ◽

pp. 73-78 ◽

Cited By ~ 63

Author(s):

Ghazi Kayali ◽

Sharon F. Setterquist ◽

Ana W. Capuano ◽

Kendall P. Myers ◽

James S. Gill ◽

...

Keyword(s):

Avian Influenza ◽

Hemagglutination Inhibition ◽

Influenza Viruses ◽

Avian Influenza Viruses ◽

Human Sera

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The Multifaceted Zoonotic Risk of H9N2 Avian Influenza

Veterinary Sciences ◽

10.3390/vetsci5040082 ◽

2018 ◽

Vol 5 (4) ◽

pp. 82 ◽

Cited By ~ 22

Author(s):

Elizabeth Pusch ◽

David Suarez

Keyword(s):

Avian Influenza ◽

Severe Pneumonia ◽

Cell Receptor ◽

Influenza Viruses ◽

Effective Vaccine ◽

Upper Respiratory Tract ◽

Zoonotic Risk ◽

Occupationally Exposed ◽

Upper Respiratory ◽

Almost All

Poultry-adapted H9N2 avian influenza viruses (AIVs) are commonly found in many countries in Asia, the Middle East, Africa, and Europe, and although classified as low pathogenic viruses, they are an economically important disease. Besides the importance of the disease in the poultry industry, some H9N2 AIVs are also known to be zoonotic. The disease in humans appears to cause primarily a mild upper respiratory disease, and doesn’t cause or only rarely causes the severe pneumonia often seen with other zoonotic AIVs like H5N1 or H7N9. Serologic studies in humans, particularly in occupationally exposed workers, show a large number of people with antibodies to H9N2, suggesting infection is commonly occurring. Of the four defined H9N2 poultry lineages, only two lineages, the G1 and the Y280 lineages, are associated with human infections. Almost all of the viruses from humans have a leucine at position 226 (H3 numbering) of the hemagglutinin associated with a higher affinity of binding with α2,6 sialic acid, the host cell receptor most commonly found on glycoproteins in the human upper respiratory tract. For unknown reasons there has also been a shift in recent years of poultry viruses in the G1 and Y280 lineages to also having leucine instead of glutamine, the amino acid found in most avian viruses, at position 226. The G1 and Y280 poultry lineages because of their known ability to infect humans, the high prevalence of the virus in poultry in endemic countries, the lack of antibody in most humans, and the shift of poultry viruses to more human-like receptor binding makes these viruses a human pandemic threat. Increased efforts for control of the virus, including through effective vaccine use in poultry, is warranted for both poultry and public health goals.

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A comprehensive retrospective study of the seroprevalence of H9N2 avian influenza viruses in occupationally exposed populations in China

PLoS ONE ◽

10.1371/journal.pone.0178328 ◽

2017 ◽

Vol 12 (6) ◽

pp. e0178328 ◽

Cited By ~ 12

Author(s):

Xin Li ◽

Bai Tian ◽

Zhou Jianfang ◽

Chen Yongkun ◽

Li Xiaodan ◽

...

Keyword(s):

Retrospective Study ◽

Avian Influenza ◽

Influenza Viruses ◽

Avian Influenza Viruses ◽

Occupationally Exposed

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H7N9 Avian Influenza A Virus and the Perpetual Challenge of Potential Human Pandemicity

mBio ◽

10.1128/mbio.00445-13 ◽

2013 ◽

Vol 4 (4) ◽

Cited By ~ 37

Author(s):

David M. Morens ◽

Jeffery K. Taubenberger ◽

Anthony S. Fauci

Keyword(s):

Avian Influenza ◽

Influenza A ◽

Opportunity To Learn ◽

Public Health Research ◽

Influenza Viruses ◽

Human Adaptation ◽

Avian Influenza Viruses ◽

Human Interface ◽

Clinical Syndromes ◽

Avian Influenza A Virus

ABSTRACT The ongoing H7N9 influenza epizootic in China once again presents us questions about the origin of pandemics and how to recognize them in early stages of development. Over the past ~135 years, H7 influenza viruses have neither caused pandemics nor been recognized as having undergone human adaptation. Yet several unusual properties of these viruses, including their poultry epizootic potential, mammalian adaptation, and atypical clinical syndromes in rarely infected humans, suggest that they may be different from other avian influenza viruses, thus questioning any assurance that the likelihood of human adaptation is low. At the same time, the H7N9 epizootic provides an opportunity to learn more about the mammalian/human adaptational capabilities of avian influenza viruses and challenges us to integrate virologic and public health research and surveillance at the animal-human interface.

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Avian influenza viruses at the animal human interface: Progress and challenges in under resourced countries

International Journal of Infectious Diseases ◽

10.1016/j.ijid.2016.11.064 ◽

2016 ◽

Vol 53 ◽

pp. 24

Author(s):

G. Cattoli

Keyword(s):

Avian Influenza ◽

Influenza Viruses ◽

Avian Influenza Viruses ◽

Human Interface

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Epidemiological investigation of avian influenza in regions of Northern Greece

Journal of the Hellenic Veterinary Medical Society ◽

10.12681/jhvms.15369 ◽

2018 ◽

Vol 53 (2) ◽

pp. 132

Author(s):

J. PAPANIKOLAOU (I. ΠΑΠΑΝΙΚΟΛΑΟΥ) ◽

M. KOUMBATI-ARTOPIOU (Μ. ΚΟΥΜΠΑΤΗ-ΑΡΤΟΠΟΙΟΥ)

Keyword(s):

Avian Influenza ◽

Egg Production ◽

Virus Isolation ◽

Wild Birds ◽

Influenza Viruses ◽

Surveillance Program ◽

Avian Influenza Viruses ◽

Serum Samples ◽

Northern Greece ◽

Serological Tests

The results of an avian influenza viruses surveillance program in chicken and turkey industrial flocks, as well as in some wild birds from regions of N. Greece during 1999-2000 are presented in this paper. For this purpose, avian influenza virus isolation was attempted by inoculation of samples from chickens and wild birds into embryonated chicken eggs. The samples originated from 35-60 week-old layers and breeders with mild respiratory signs and drop in egg production. 34 wild birds (sparrows, chaffinchs, gulls), that were brought dead to the laboratory of Veterinary Research Institute of Thessaloniki, were also examined in order to investigate the cause of their death. At the same time, 720 serum samples from 30 chicken and 6 turkey flocks were examined by Agar Gel Immunodiffusion (AGID) test. During the same period and in the framework of a surveillance program for avian influenza viruses in Greece, 2580 paired serum samples from chicks were tested by AGID test. Chicks were imported from Italy, where a Highly Pathogenic Avian Influenza was in progress during 1999-2000. All virus isolation attempts and serological tests were negative.

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