Public Health Risk from Avian Influenza Viruses

ABSTRACT The cocirculation of H5N1 and H9N2 avian influenza viruses in birds in Egypt provides reassortment opportunities between these two viruses. However, little is known about the emergence potential of reassortants derived from Egyptian H5N1 and H9N2 viruses and about the biological properties of such reassortants. To evaluate the potential public health risk of reassortants of these viruses, we used reverse genetics to generate the 63 possible reassortants derived from contemporary Egyptian H5N1 and H9N2 viruses, containing the H5N1 surface gene segments and combinations of the H5N1 and H9N2 internal gene segments, and analyzed their genetic compatibility, replication ability, and virulence in mice. Genes in the reassortants showed remarkably high compatibility. The replication of most reassortants was higher than the parental H5N1 virus in human cells. Six reassortants were thought to emerge in birds under neutral or positive selective pressure, and four of them had higher pathogenicity in vivo than the parental H5N1 and H9N2 viruses. Our results indicated that H5N1-H9N2 reassortants could be transmitted efficiently to mammals with significant public health risk if they emerge in Egypt, although the viruses might not emerge frequently in birds. IMPORTANCE Close interaction between avian influenza (AI) viruses and humans in Egypt appears to have resulted in many of the worldwide cases of human infections by both H5N1 and H9N2 AI viruses. Egypt is regarded as a hot spot of AI virus evolution. Although no natural reassortant of H5N1 and H9N2 AI viruses has been reported so far, their cocirculation in Egypt may allow emergence of reassortants that may present a significant public health risk. Using reverse genetics, we report here the first comprehensive data showing that H5N1-N9N2 reassortants have fairly high genetic compatibility and possibly higher pathogenicity in mammals, including humans, than the parental viruses. Our results provide insight into the emergence potential of avian H5N1-H9N2 reassortants that may pose a high public health risk.

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H5N1 infections in cats – public health implications

Weekly releases (1997–2007) ◽

10.2807/esw.11.15.02942-en ◽

2006 ◽

Vol 11 (15) ◽

Author(s):

Collective Influenza team (ECDC)

Keyword(s):

Public Health ◽

Avian Influenza ◽

Influenza Viruses ◽

Avian Influenza Viruses ◽

Animal Group ◽

Health Implications ◽

Natural Reservoir ◽

Pathogenic Avian Influenza ◽

Low Pathogenic Avian Influenza

The natural reservoir of influenza viruses is generally considered to be wild waterbirds. In this animal group, many species of influenza viruses circulate without seeming to cause much disease, and are therefore known as ‘low pathogenic’ avian influenza viruses

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The Impact of Avian Influenza Viruses on Public Health

Avian Diseases ◽

10.1637/0005-2086-47.s3.914 ◽

2003 ◽

Vol 47 (s3) ◽

pp. 914-920 ◽

Cited By ~ 20

Author(s):

J. M. Katz

Keyword(s):

Public Health ◽

Avian Influenza ◽

Influenza Viruses ◽

Avian Influenza Viruses ◽

The Impact

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Continuous Reassortment of Clade 2.3.4.4 H5N6 Highly Pathogenetic Avian Influenza Viruses Demonstrating High Risk to Public Health

Pathogens ◽

10.3390/pathogens9080670 ◽

2020 ◽

Vol 9 (8) ◽

pp. 670 ◽

Cited By ~ 1

Author(s):

Huanan Li ◽

Qian Li ◽

Bo Li ◽

Yang Guo ◽

Jinchao Xing ◽

...

Keyword(s):

Public Health ◽

High Risk ◽

Avian Influenza ◽

Migratory Birds ◽

Influenza Pandemic ◽

Influenza Viruses ◽

Avian Influenza Viruses ◽

The World

Since it firstly emerged in China in 2013, clade 2.3.4.4 H5N6 highly pathogenic avian influenza viruses (HPAIVs) has rapidly replaced predominant H5N1 to become the dominant H5 subtype in China, especially in ducks. Not only endemic in China, it also crossed the geographical barrier and emerged in South Korea, Japan, and Europe. Here, we analyzed the genetic properties of the clade 2.3.4.4 H5N6 HPAIVs with full genome sequences available online together with our own isolates. Phylogenetic analysis showed that clade 2.3.4.4 H5N6 HPAIVs continuously reassorted with local H5, H6, and H7N9/H9N2. Species analysis reveals that aquatic poultry and migratory birds became the dominant hosts of H5N6. Adaption to aquatic poultry might help clade 2.3.4.4 H5N6 better adapt to migratory birds, thus enabling it to become endemic in China. Besides, migratory birds might help clade 2.3.4.4 H5N6 transmit all over the world. Clade 2.3.4.4 H5N6 HPAIVs also showed a preference for α2,6-SA receptors when compared to other avian origin influenza viruses. Experiments in vitro and in vivo revealed that clade 2.3.4.4 H5N6 HPAIVs exhibited high replication efficiency in both avian and mammal cells, and it also showed high pathogenicity in both mice and chickens, demonstrating high risk to public health. Considering all the factors together, adaption to aquatic poultry and migratory birds helps clade 2.3.4.4 H5N6 overcome the geographical isolation, and it has potential to be the next influenza pandemic in the world, making it worthy of our attention.

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Wipes Coated with a Singlet-Oxygen-Producing Photosensitizer Are Effective against Human Influenza Virus but Not against Norovirus

Applied and Environmental Microbiology ◽

10.1128/aem.01219-14 ◽

2014 ◽

Vol 80 (14) ◽

pp. 4391-4397 ◽

Cited By ~ 3

Author(s):

Katharina Verhaelen ◽

Martijn Bouwknegt ◽

Saskia Rutjes ◽

Ana Maria de Roda Husman ◽

Erwin Duizer

Keyword(s):

Public Health ◽

Influenza Virus ◽

Health Risk ◽

Singlet Oxygen ◽

Human Adenovirus ◽

Influenza Viruses ◽

Murine Norovirus ◽

Human Influenza ◽

Human Influenza Virus ◽

Public Health Risk

ABSTRACTTransmission of enteric and respiratory viruses, including human norovirus (hNoV) and human influenza virus, may involve surfaces. In food preparation and health care settings, surfaces are cleaned with wipes; however, wiping may not efficiently reduce contamination or may even spread viruses, increasing a potential public health risk. The virucidal properties of wipes with a singlet-oxygen-generating immobilized photosensitizer (IPS) coating were compared to those of similar but uncoated wipes (non-IPS) and of commonly used viscose wipes. Wipes were spiked with hNoV GI.4 and GII.4, murine norovirus 1 (MNV-1), human adenovirus type 5 (hAdV-5), and influenza virus H1N1 to study viral persistence. We also determined residual and transferred virus proportions on steel carriers after successively wiping a contaminated and an uncontaminated steel carrier. On IPS wipes only, influenza viruses were promptly inactivated with a 5-log10reduction.Dvalues of infectious MNV-1 and hAdV-5 were 8.7 and 7.0 h on IPS wipes, 11.6 and 9.3 h on non-IPS wipes, and 10.2 and 8.2 h on viscose wipes, respectively. Independently of the type of wipe, dry cleaning removed, or drastically reduced, initial spot contamination of hNoV on surfaces. All wipes transferred hNoV to an uncontaminated carrier; however, the risk of continued transmission by reuse of wipes after 6 and 24 h was limited for all viruses. We conclude that cleaning wet spots with dry wipes efficiently reduced spot contamination on surfaces but that cross-contamination with noroviruses by wiping may result in an increased public health risk at high initial virus loads. For influenza virus, IPS wipes present an efficient one-step procedure for cleaning and disinfecting contaminated surfaces.

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Endemicity of H9N2 and H5N1 avian influenza viruses in poultry in China poses a serious threat to poultry industry and public health

Frontiers of Agricultural Science and Engineering ◽

10.15302/j-fase-2016092 ◽

2016 ◽

Vol 3 (1) ◽

pp. 11 ◽

Cited By ~ 2

Author(s):

Jiao HU ◽

Xiufan LIU

Keyword(s):

Public Health ◽

Avian Influenza ◽

Influenza Viruses ◽

Poultry Industry ◽

Avian Influenza Viruses ◽

H5n1 Avian Influenza

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Epidemiology, Evolution, and Recent Outbreaks of Avian Influenza Virus in China

Journal of Virology ◽

10.1128/jvi.01034-15 ◽

2015 ◽

Vol 89 (17) ◽

pp. 8671-8676 ◽

Cited By ~ 143

Author(s):

Shuo Su ◽

Yuhai Bi ◽

Gary Wong ◽

Gregory C. Gray ◽

George F. Gao ◽

...

Keyword(s):

Public Health ◽

Influenza Virus ◽

Avian Influenza ◽

Avian Influenza Virus ◽

Influenza Viruses ◽

Warning Signs ◽

Avian Influenza Viruses ◽

Recent Increase ◽

And Control

Novel reassortants of H7N9, H10N8, and H5N6 avian influenza viruses (AIVs) are currently circulating in China's poultry flocks, occasionally infecting humans and other mammals. Combined with the sometimes enzootic H5N1 and H9N2 strains, this cauldron of genetically diverse AIVs pose significant risks to public health. Here, we review the epidemiology, evolution, and recent outbreaks of AIVs in China, discuss reasons behind the recent increase in the emergence of novel AIVs, and identify warning signs which may point to the emergence of a potentially virulent and highly transmissible AIV to humans. This review will be useful to authorities who consider options for the detection and control of AIV transmission in animals and humans, with the goal of preventing future epidemics and pandemics.

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A Novel A(H7N2) Influenza Virus Isolated from a Veterinarian Caring for Cats in a New York City Animal Shelter Causes Mild Disease and Transmits Poorly in the Ferret Model

Journal of Virology ◽

10.1128/jvi.00672-17 ◽

2017 ◽

Vol 91 (15) ◽

Cited By ~ 14

Author(s):

Jessica A. Belser ◽

Joanna A. Pulit-Penaloza ◽

Xiangjie Sun ◽

Nicole Brock ◽

Claudia Pappas ◽

...

Keyword(s):

Public Health ◽

United States ◽

New York ◽

New York City ◽

Occupational Exposure ◽

Avian Influenza ◽

York City ◽

Influenza Viruses ◽

Northeastern United States ◽

Avian Influenza Viruses

ABSTRACT In December 2016, a low-pathogenic avian influenza (LPAI) A(H7N2) virus was identified to be the causative source of an outbreak in a cat shelter in New York City, which subsequently spread to multiple shelters in the states of New York and Pennsylvania. One person with occupational exposure to infected cats became infected with the virus, representing the first LPAI H7N2 virus infection in a human in North America since 2003. Considering the close contact that frequently occurs between companion animals and humans, it was critical to assess the relative risk of this novel virus to public health. The virus isolated from the human case, A/New York/108/2016 (NY/108), caused mild and transient illness in ferrets and mice but did not transmit to naive cohoused ferrets following traditional or aerosol-based inoculation methods. The environmental persistence of NY/108 virus was generally comparable to that of other LPAI H7N2 viruses. However, NY/108 virus replicated in human bronchial epithelial cells with an increased efficiency compared with that of previously isolated H7N2 viruses. Furthermore, the novel H7N2 virus was found to utilize a relatively lower pH for hemagglutinin activation, similar to human influenza viruses. Our data suggest that the LPAI H7N2 virus requires further adaptation before representing a substantial threat to public health. However, the reemergence of an LPAI H7N2 virus in the northeastern United States underscores the need for continuous surveillance of emerging zoonotic influenza viruses inclusive of mammalian species, such as domestic felines, that are not commonly considered intermediate hosts for avian influenza viruses. IMPORTANCE Avian influenza viruses are capable of crossing the species barrier to infect mammals, an event of public health concern due to the potential acquisition of a pandemic phenotype. In December 2016, an H7N2 virus caused an outbreak in cats in multiple animal shelters in New York State. This was the first detection of this virus in the northeastern United States in over a decade and the first documented infection of a felid with an H7N2 virus. A veterinarian became infected following occupational exposure to H7N2 virus-infected cats, necessitating the evaluation of this virus for its capacity to cause disease in mammals. While the H7N2 virus was associated with mild illness in mice and ferrets and did not spread well between ferrets, it nonetheless possessed several markers of virulence for mammals. These data highlight the promiscuity of influenza viruses and the need for diligent surveillance across multiple species to quickly identify an emerging strain with pandemic potential.

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