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Berhane, Y.

Publications and source records attributed to Berhane, Y..

4 recordsLinked to original sources

Detection of a reassortant swine- and human-origin H3N2 influenza A virus in farmed mink in British Columbia, Canada

In December 2021, influenza A viruses (IAV) were detected in a population of farmed mink in British Columbia, Canada. Based on genomic sequencing and phylogenetic analysis, these IAVs were subtyped as H3N2s that originated from reassortment of swine H3N2 (clade 1990.4h), human seasonal H1N1 (pdm09), and swine H1N2 (clade 1A.1.1.3). This reassortant has been subsequently observed in swine in several Midwest American states, as well as in swine and turkeys in Ontario, suggesting its spillover into farmed mink in British Columbia was incidental to its broader dissemination in North American swine populations. These detections reaffirm the need for extensive genomic surveillance of IAVs in swine populations to monitor reassortments that might become public health concerns. They also highlight the need for closer surveillance of IAVs in mink to preserve animal health, protect agricultural interests, and monitor potential zoonotic threats.

microbiology↗

Avian influenza virus circulation and immunity in a wild urban duck population prior to and during a highly pathogenic H5N1 outbreak

Highly pathogenic avian influenza (HPAI) H5N1 clade 2.3.4.4b viruses were first detected in St. Johns, Newfoundland, Canada in late 2021, with the virus rapidly spreading across the western hemisphere over the next year. To investigate the patterns of avian influenza virus (AIV) infection and immune responses subsequent to the arrival of H5N1, we sampled the wild urban duck population in St. Johns for a period of 16 months after the start of the outbreak and compared these findings to archived samples. Antibody seroprevalence was relatively stable before the outbreak (2011-2014) at 27.6% and 3.9% for anti-AIV (i.e., NP) and H5-specific antibodies, respectively. During the winter of 2022, AIV-NP and H5-specific antibody seroprevalence both reached 100%, signifying a population-wide infection event. As expected, population-level immunity waned over time, and we found that ducks were seropositive for anti- AIV-NP antibodies for around twice as long as for H5-specific antibodies. The population was H5 seronegative to the latter approximately six months after the initial H5N1 incursion. In late February 2023, H5N1 clade 2.3.4.4b viruses were again detected in the duck population as a result of a second incursion into Newfoundland from Eurasia, which resulted in a second population-wide infection event. We observed a clear relationship of increasing antibody levels with decreasing viral RNA loads that allowed for interpretation of the course of infection and immune response in infected individuals and applied these findings to two cases of resampled ducks to infer infection history. Our study highlights the significance of applying both AIV surveillance and seroprevalence monitoring to provide a better understanding of AIV dynamics in wild populations, which may be crucial following the arrival of 2.3.4.4b H5Nx subtypes to assess the threats they pose to both wild and domestic animals, and to humans.

microbiology↗

Avian influenza viruses in wild birds in Canada following incursion of the highly pathogenic H5N1 virus from Eurasia in 2021/2022

Following detection of novel highly pathogenic avian influenza virus (HPAIV) H5N1 clade 2.3.4.4b in Newfoundland, Canada in late 2021, avian influenza surveillance in wild birds was scaled-up across Canada. Herein, we present results of Canadas Interagency Surveillance Program for Avian Influenza in wild birds during the first year (November 2021 - November 2022) following the incursions of HPAIV from Eurasia. Key objectives of the surveillance program were to (i) detect the presence, distribution and spread of HPAIV and other avian influenza viruses (AIVs), (ii) detect wild bird morbidity and mortality associated with HPAIV, (iii) identify the range of wild bird species infected by HPAIV, and (iv) characterize detected AIV. A total of 6,246 sick and dead wild birds were tested, of which 27.4% were HPAIV positive across 12 taxonomic orders and 80 species. Geographically, HPAIV detections occurred in all Canadian provinces and territories, with the highest numbers in the Atlantic and Central flyways. Temporally, peak detections differed across flyways, though the national peak occurred in April 2022. In an additional 11,295 asymptomatic harvested or live captured wild birds, 5.2% were HPAIV positive across 3 taxonomic orders and 19 species. Whole genome sequencing identified HPAIV of Eurasian origin as most prevalent in the Atlantic flyway, along with multiple reassortants of mixed Eurasian and North American origins distributed across Canada, with moderate structuring at the flyway scale. Wild birds were victims and reservoirs of HPAIV H5N1 2.3.4.4b, underscoring the importance of surveillance encompassing samples from sick and dead, as well as live and harvested birds to provide insights into the dynamics and potential impacts of the HPAIV H5N1 outbreak. This dramatic shift in presence and distribution of HPAIV in wild birds in Canada highlights a need for sustained investment in wild bird surveillance and collaboration across One Health partners.

zoology↗

Outbreak of Highly Pathogenic Avian Influenza Virus H5N1 in Seals in the St. Lawrence Estuary, Quebec, Canada

We describe an unusual mortality event caused by a highly pathogenic avian influenza virus (HPAI) H5N1 clade 2.3.4.4b involving harbor (Phoca vitulina) and grey (Halichoerus grypus) seals in the St. Lawrence Estuary, Quebec, Canada. Fifteen (56%) of the seals submitted for necropsy were considered to be fatally infected by H5N1 containing fully Eurasian (EA) or Eurasian/North American genome constellation. Concurrently, presence of large numbers of bird carcasses infected with H5N1 at haul-out sites most likely contributed to the spill-over of infection to the seals. Histologic changes included meningoencephalitis (100%), fibrinosuppurative alveolitis, and multi-organ acute necrotizing inflammation. This is the first report of fatal H5N1 infection in pinnipeds in Canada, raising concerns about the expanding host of this virus, potential for establishment of a marine mammal reservoir, and the public health risks associated with spillover to mammals.

pathology↗