Graph-guided multi-task sparse learning model: a method for identifying antigenic variants of influenza A(H3N2) virus

The efficacy for direct immunofluorescence of a commercial conjugate for influenza A virus prepared against whole A/Udorn (H3NS) virus was studied. The conjugate was specific for influenza A virus, but its sensitivity varied depending upon the strain of influenza A tested. Nasopharyngeal aspirates collected from 25 patients during an outbreak of influenza were examined for viral antigen with the conjugates and inoculated onto monkey kidney (MK) cells for virus isolation. Fifteen patients had isolates for influenza A/USSR/90/77 (H1N1); nasopharyngeal secretions were fluorescent antibody positive in 12. Fluorescent antibody was copositive with culture in 11/15 patients (73.3%) and conegative in 9/10 (90%). The one fluorescent antibody-positive, culture-negative patient had negative serology for influenza A and the fluorescent antibody result was considered to be a false positive. At a 1:10 dilution, the conjugate stained nasopharyngeal and MK cells infected with A/USSR (H1N1) 2 to 3+, whereas cells infected with H3N2 virus stained 4+. A conjugate made specifically against the ribonucleoprotein antigen, which is universal to all influenza A strains, may improve the sensitivity of the direct immunofluorescent test.

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Pre-exposure with influenza A virus A/WSN/1933(H1N1) resulted in viral shedding reduction from pigs challenged with either swine H1N1 or H3N2 virus

Veterinary Microbiology ◽

10.1016/j.vetmic.2018.11.008 ◽

2019 ◽

Vol 228 ◽

pp. 26-31 ◽

Cited By ~ 1

Author(s):

Zhao Wang ◽

Jieshi Yu ◽

Milton Thomas ◽

Chithra C. Sreenivasan ◽

Ben M. Hause ◽

...

Keyword(s):

Influenza A Virus ◽

Influenza A ◽

H3n2 Virus ◽

Viral Shedding

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Multiple Influenza A (H3N2) Mutations Conferring Resistance to Neuraminidase Inhibitors in a Bone Marrow Transplant Recipient

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.03667-14 ◽

2014 ◽

Vol 58 (12) ◽

pp. 7188-7197 ◽

Cited By ~ 37

Author(s):

Alireza Eshaghi ◽

Sarah Shalhoub ◽

Paul Rosenfeld ◽

Aimin Li ◽

Rachel R. Higgins ◽

...

Keyword(s):

Influenza Virus ◽

Antiviral Therapy ◽

Influenza A ◽

Antiviral Treatment ◽

Marrow Transplant ◽

Viral Fitness ◽

H3n2 Virus ◽

Resistance Mutations ◽

Depth Analysis ◽

Resistant Strains

ABSTRACTImmunocompromised patients are predisposed to infections caused by influenza virus. Influenza virus may produce considerable morbidity, including protracted illness and prolonged viral shedding in these patients, thus prompting higher doses and prolonged courses of antiviral therapy. This approach may promote the emergence of resistant strains. Characterization of neuraminidase (NA) inhibitor (NAI)-resistant strains of influenza A virus is essential for documenting causes of resistance. In this study, using quantitative real-time PCR along with conventional Sanger sequencing, we identified an NAI-resistant strain of influenza A (H3N2) virus in an immunocompromised patient. In-depth analysis by deep gene sequencing revealed that various known markers of antiviral resistance, including transient R292K and Q136K substitutions and a sustained E119K (N2 numbering) substitution in the NA protein emerged during prolonged antiviral therapy. In addition, a combination of a 4-amino-acid deletion at residues 245 to 248 (Δ245-248) accompanied by the E119V substitution occurred, causing resistance to or reduced inhibition by NAIs (oseltamivir, zanamivir, and peramivir). Resistant variants within a pool of viral quasispecies arose during combined antiviral treatment. More research is needed to understand the interplay of drug resistance mutations, viral fitness, and transmission.

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Natural co-infection of influenza A/H3N2 and A/H1N1pdm09 viruses resulting in a reassortant A/H3N2 virus

Journal of Clinical Virology ◽

10.1016/j.jcv.2015.11.008 ◽

2015 ◽

Vol 73 ◽

pp. 108-111 ◽

Cited By ~ 7

Author(s):

Sareth Rith ◽

Savuth Chin ◽

Borann Sar ◽

Phalla Y ◽

Srey Viseth Horm ◽

...

Keyword(s):

Influenza A ◽

H3n2 Virus

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Bat influenza vectored NS1-truncated live vaccine protects pigs against heterologous virus challenge

10.1101/2020.11.18.389254 ◽

2020 ◽

Author(s):

Jinhwa Lee ◽

Yonghai Li ◽

Yuhao Li ◽

A. Giselle Cino-Ozuna ◽

Michael Duff ◽

...

Keyword(s):

Influenza Virus ◽

Influenza A ◽

Swine Influenza Virus ◽

Swine Influenza ◽

Live Vaccine ◽

H3n2 Virus ◽

Swine Industry ◽

Vaccine Candidates ◽

Virus Challenge ◽

Significant Difference

AbstractSwine influenza is an important disease for the swine industry. Currently used whole inactivated virus (WIV) vaccines can induce vaccine-associated enhanced respiratory disease (VAERD) in pigs when the vaccine strains mismatch with the infected viruses. Live attenuated influenza virus vaccine (LAIV) is effective to protect pigs against homologous and heterologous swine influenza virus infections without inducing VAERD, but has safety concerns due to potential reassortment with circulating viruses. Herein, we used a chimeric bat influenza Bat09:mH3mN2 virus, which contains both surface HA and NA gene open reading frames of the A/swine/Texas/4199-2/1998 (H3N2) and six internal genes from the novel bat H17N10 virus, to develop modified live-attenuated viruses (MLVs) as vaccine candidates which cannot reassort with canonical influenza A viruses by co-infection. Two attenuated MLV vaccine candidates including the virus that expresses a truncated NS1 (Bat09:mH3mN2-NS1-128, MLV1) or expresses both a truncated NS1 and the swine IL-18 (Bat09:mH3mN2-NS1-128-IL-18, MLV2) were generated and evaluated in pigs against a heterologous H3N2 virus using the WIV vaccineb as a control. Compared to the WIV vaccine, both MLV vaccines were able to reduce lesions and virus replication in lungs and limit nasal virus shedding without VAERD, also induced significantly higher levels of mucosal IgA response in lungs and significantly increased numbers of antigen-specific IFN-γ secreting cells against the challenge virus. However, no significant difference was observed in efficacy between the MLV1 and MLV2. These results indicate that bat influenza vectored MLV vaccines can be used as a safe live vaccine to prevent swine influenza.

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Influenza outbreaks in nursing homes with high vaccination coverage in Navarre, Spain, 2011/12

Eurosurveillance ◽

10.2807/ese.17.14.20141-en ◽

2012 ◽

Vol 17 (14) ◽

Author(s):

J Castilla ◽

F Cía ◽

J Zubicoa ◽

G Reina ◽

V Martínez-Artola ◽

...

Keyword(s):

Nursing Homes ◽

Early Detection ◽

Virus Strain ◽

Vaccination Coverage ◽

Influenza A ◽

H3n2 Virus ◽

Hygiene Measures ◽

Influenza Outbreaks

In the 2011/12 season, three influenza outbreaks were studied in nursing homes with high vaccination coverage in Navarre, Spain. Attack rates ranged from 2.9% to 67%. Influenza A/Stockholm/18/2011(H3N2) virus strain was isolated from the three outbreaks. Vaccination should be complemented with other hygiene measures in nursing homes. Early detection of influenza outbreaks in nursing homes can aid in their control.

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Seasonality of Influenza A(H3N2) Virus: A Hong Kong Perspective (1997–2006)

PLoS ONE ◽

10.1371/journal.pone.0002768 ◽

2008 ◽

Vol 3 (7) ◽

pp. e2768 ◽

Cited By ~ 26

Author(s):

Julian W. Tang ◽

Karry L. K. Ngai ◽

Wai Y. Lam ◽

Paul K. S. Chan

Keyword(s):

Hong Kong ◽

Influenza A ◽

H3n2 Virus

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