Outbreak of Highly Pathogenic Avian Influenza A(H5N1) Virus in Seals, St. Lawrence Estuary, Quebec, Canada1.

We describe an unusual mortality event caused by a highly pathogenic avian influenza (HPAI) A(H5N1) virus clade 2.3.4.4b involving harbor (Phoca vitulina) and gray (Halichoerus grypus) seals in the St. Lawrence Estuary, Quebec, Canada, in 2022. Fifteen (56%) of the seals submitted for necropsy were considered to be fatally infected by HPAI H5N1 containing fully Eurasian or Eurasian/North American genome constellations. Concurrently, presence of large numbers of bird carcasses infected with HPAI H5N1 at seal haul-out sites most likely contributed to the spillover of infection to the seals. Histologic changes included meningoencephalitis (100%), fibrinosuppurative alveolitis, and multiorgan acute necrotizing inflammation. This report of fatal HPAI H5N1 infection in pinnipeds in Canada raises concerns about the expanding host of this virus, the potential for the establishment of a marine mammal reservoir, and the public health risks associated with spillover to mammals.Nous décrivons un événement de mortalité inhabituelle causé par un virus de l'influenza aviaire hautement pathogène A(H5N1) clade 2.3.4.4b chez des phoques communs (Phoca vitulina) et gris (Halichoerus grypus) dans l'estuaire du Saint-Laurent au Québec, Canada, en 2022. Quinze (56%) des phoques soumis pour nécropsie ont été considérés comme étant fatalement infectés par le virus H5N1 de lignées eurasiennes ou de réassortiment eurasiennes/nord-américaines. Un grand nombre simultané de carcasses d'oiseaux infectés par le H5N1 sur les sites d'échouement a probablement contribué à la contamination de ces phoques. Les changements histologiques associés à cette infection incluaient : méningo-encéphalite (100%), alvéolite fibrinosuppurée et inflammation nécrosante aiguë multi-organique. Cette documentation soulève des préoccupations quant à l'émergence de virus mortels, à la possibilité d'établissement de réservoirs chez les mammifères marins, et aux risques pour la santé publique associés aux propagations du virus chez les mammifères.

Patient Satisfaction with the Implementation of Telehealth in Ambulatory Care during the COVID-19 Pandemic: A Single Institution Experience.

Background: COVID-19 has reduced the capacity for delivering essential health services due to lockdown restrictions. Telehealth is an effective alternative option to improve healthcare access. However, there remain implementation challenges to patient adoption in resource-limited settings such as Ethiopia. Therefore, the purpose of this study was to assess patient satisfaction following the implementation of telehealth in ambulatory settings during the COVID-19 pandemic. Methods: A cross-sectional study was conducted at Ayder Comprehensive Specialized Hospital in the Tigray region of Northern Ethiopia. Patients who used the telehealth service were invited to participate in a patient satisfaction survey. All statistical analyses were performed using STATA Version 14.1. Result: A total of 149 patients have participated in the survey. Out of the total participants, 129 (86.6%) found that telehealth is easy to understand and overall satisfaction for telehealth was 87.9%. About two-thirds of the patients (97, 65.1%) reported that the telehealth visit is just as good as a traditional visit. The vast majority of participants (148, 98.6%) stated that they would definitely or probably use telehealth again and would recommend it to others. The majority of respondents (137, 91.9%) followed the recommendations provided. Conclusion: Patients have a high level of satisfaction with the use of telehealth during the COVID-19 pandemic. About two-thirds of patients said the telehealth visit was just as good as a traditional visit. The majority of patients followed the recommendations given to them by the healthcare providers and stated that they would definitely or probably use telehealth in the future and would recommend it to others. This high level of patient satisfaction with telehealth implementation suggests that the service could be considered in low-income countries as well.

Antimicrobial Use-Related Problems Among Hospitalized Pediatric Patients: A Prospective Observational Study.

Introduction: Antimicrobials are among the most commonly misused medications, leading to antimicrobial resistance, and therefore demand more attention. There are limited studies documenting "antimicrobial use-related problems" in developing countries, especially in pediatric patients. Objectives: This study aimed to evaluate the prevalence of antimicrobial use-related problems and risk factors among hospitalized pediatric patients. Materials and Methods: A hospital-based prospective observational study was conducted in Ayder comprehensive specialized hospital (ACSH) in the Tigray region, Ethiopia. The participants of the study were pediatric patients aged ≤15 years who were admitted with a diagnosis of infectious disease between September 2019 and November 2019. Results: A total of 232 pediatric patients were included in the study. Of these, 59.5% of the patients were male and the mean age (SD) of the patients was 5.8 (5.2) years. Of the 232 patients surveyed, a total of 177 antimicrobial use-related problems were identified. One or more antimicrobial use-related problems have occurred in more than half of the patients (53.9%). The commonest antimicrobial use problems were unnecessary antimicrobial therapy (22.8%) followed by need additional antimicrobial therapy (16.4%). In a multivariate logistic regression model, patients with comorbidities (Adjusted odds ratio (AOR): 1.84, 95% confidence interval (CI): 1.04-3.27) and hospital stays exceeding one week (AOR=1.88, 95% CI: 1.08-3.26) were predictors of antimicrobial use-related problems. Conclusion: Antimicrobial use-related problems were found in a significant proportion of pediatric patients. Addressing these issues necessitates collaborative efforts, emphasizing targeted education, strengthened antimicrobial stewardship, ensuring responsible antimicrobial use and enhancing pediatric care.

Recurring Trans-Atlantic Incursion of Clade 2.3.4.4b H5N1 Viruses by Long Distance Migratory Birds from Northern Europe to Canada in 2022/2023.

In December 2022 and January 2023, we isolated clade 2.3.4.4b H5N1 high-pathogenicity avian influenza (HPAI) viruses from six American crows (Corvus brachyrhynchos) from Prince Edward Island and a red fox (Vulpes vulpes) from Newfoundland, Canada. Using full-genome sequencing and phylogenetic analysis, these viruses were found to fall into two distinct phylogenetic clusters: one group containing H5N1 viruses that had been circulating in North and South America since late 2021, and the other one containing European H5N1 viruses reported in late 2022. The transatlantic re-introduction for the second time by pelagic/Icelandic bird migration via the same route used during the 2021 incursion of Eurasian origin H5N1 viruses into North America demonstrates that migratory birds continue to be the driving force for transcontinental dissemination of the virus. This new detection further demonstrates the continual long-term threat of H5N1 viruses for poultry and mammals and the subsequent impact on various wild bird populations wherever these viruses emerge. The continual emergence of clade 2.3.4.4b H5Nx viruses requires vigilant surveillance in wild birds, particularly in areas of the Americas, which lie within the migratory corridors for long-distance migratory birds originating from Europe and Asia. Although H5Nx viruses have been detected at higher rates in North America since 2021, a bidirectional flow of H5Nx genes of American origin viruses to Europe has never been reported. In the future, coordinated and systematic surveillance programs for HPAI viruses need to be launched between European and North American agencies.

Influenza A(H5N1) Virus Infections in 2 Free-Ranging Black Bears (Ursus americanus), Quebec, Canada.

Wholly Eurasian highly pathogenic avian influenza H5N1 clade 2.3.4.4b virus was isolated from 2 free-ranging black bears with meningoencephalitis in Quebec, Canada. We found that isolates from both animals had the D701N mutation in the polymerase basic 2 gene, previously known to promote adaptation of H5N1 viruses to mammal hosts.

Second-Line Antiretroviral Treatment Outcomes and Predictors in Tigray Region, Ethiopia.

Introduction: Ethiopia has one of the highest HIV burdens in sub-Saharan Africa. Despite the fact that second-line antiretroviral therapy (ART) has been available for more than ten years, studies on its effectiveness are scarce. Objective: To assess treatment outcomes and predictors of unfavorable outcomes in HIV patients receiving second-line ART at Ayder Comprehensive Specialized Hospital and Mekelle Hospital. Materials and Methods: An institution-based retrospective cohort study was conducted in two hospitals in Tigray Region, Ethiopia. We evaluated 192 patients aged ≥15 years who were switched to second-line from November 2009 to May 2020 after failure of first-line ART. The primary outcome was the time from the initiation of second-line ART to the occurrence of unfavorable treatment outcomes (treatment failure, death, and loss to follow-up). We performed Kaplan-Meier survival estimates to calculate the cumulative incidence rates of unfavorable outcomes. Results: The mean age (SD) at the initiation of second-line ART was 39 (10.03) years, and the median CD4 cell count was 121 cells/microL. During a median follow-up of 4.6 years, 24 (12.5%) patients had died, 11 (5.7%) patients were lost to follow up, and 47 (24,4%) patients were experienced treatment failure. The incidence rates for unfavorable outcomes were 7.8 per 100 patients/years. Predictors for unfavorable outcomes were body mass index (BMI) <18.5 (adjusted hazard ratio [aHR] = 2.51, 95% confidence interval (CI): 1.27-4.95) and CD4 counts ≤100 cells/microL (aHR = 1.74, 95% CI: 1.09-2.79). Despite the failure of second-line ART, none of the patients received third-line ART. Conclusion: The incidence rate of unfavorable treatment outcomes for second-line ART was found to be high. A low BMI and a low baseline CD4 count were significant predictors of unfavourable outcomes and should be given special consideration in HIV care. A third-line ART regimen should also be considered for people who have failed second-line ART.

Rapid evolution of A(H5N1) influenza viruses after intercontinental spread to North America.

Highly pathogenic avian influenza A(H5N1) viruses of clade 2.3.4.4b underwent an explosive geographic expansion in 2021 among wild birds and domestic poultry across Asia, Europe, and Africa. By the end of 2021, 2.3.4.4b viruses were detected in North America, signifying further intercontinental spread. Here we show that the western movement of clade 2.3.4.4b was quickly followed by reassortment with viruses circulating in wild birds in North America, resulting in the acquisition of different combinations of ribonucleoprotein genes. These reassortant A(H5N1) viruses are genotypically and phenotypically diverse, with many causing severe disease with dramatic neurologic involvement in mammals. The proclivity of the current A(H5N1) 2.3.4.4b virus lineage to reassort and target the central nervous system warrants concerted planning to combat the spread and evolution of the virus within the continent and to mitigate the impact of a potential influenza pandemic that could originate from similar A(H5N1) reassortants.

Characterization of neurotropic HPAI H5N1 viruses with novel genome constellations and mammalian adaptive mutations in free-living mesocarnivores in Canada.

The GsGd lineage (A/goose/Guangdong/1/1996) H5N1 virus was introduced to Canada in 2021/2022 through the Atlantic and East Asia-Australasia/Pacific flyways by migratory birds. This was followed by unprecedented outbreaks affecting domestic and wild birds, with spillover into other animals. Here, we report sporadic cases of H5N1 in 40 free-living mesocarnivore species such as red foxes, striped skunks, and mink in Canada. The clinical presentations of the disease in mesocarnivores were consistent with central nervous system infection. This was supported by the presence of microscopic lesions and the presence of abundant IAV antigen by immunohistochemistry. Some red foxes that survived clinical infection developed anti-H5N1 antibodies. Phylogenetically, the H5N1 viruses from the mesocarnivore species belonged to clade 2.3.4.4b and had four different genome constellation patterns. The first group of viruses had wholly Eurasian (EA) genome segments. The other three groups were reassortant viruses containing genome segments derived from both North American (NAm) and EA influenza A viruses. Almost 17 percent of the H5N1 viruses had mammalian adaptive mutations (E627 K, E627V and D701N) in the polymerase basic protein 2 (PB2) subunit of the RNA polymerase complex. Other mutations that may favour adaptation to mammalian hosts were also present in other internal gene segments. The detection of these critical mutations in a large number of mammals within short duration after virus introduction inevitably highlights the need for continually monitoring and assessing mammalian-origin H5N1 clade 2.3.4.4b viruses for adaptive mutations, which potentially can facilitate virus replication, horizontal transmission and posing pandemic risks for humans.

Clinical and economic burden of healthcare-associated infections: A prospective cohort study.

INTRODUCTION: Healthcare-associated infections (HAIs) have become a serious public health problem. Despite the fact that implementing evidence-based infection control strategies could prevent HAIs and save billions of dollars, Ethiopia lacks national surveillance studies on the rate, economic, and clinical burden of HAIs. OBJECTIVE: To assess the clinical and economic burden of HAIs in hospitalized patients at Ayder comprehensive specialized hospital. MATERIALS AND METHODS: A prospective cohort study design was conducted in patients with and without HAIs. A review of medical records, interviews, and patient bills was used to extract necessary information. The patients in the two arms were matched based on age, sex, Charlson comorbidity index, and ward type. Measurable factors were compared between infected and uninfected patients using the paired ttest or McNemar's test, as appropriate. Logistic regression was used to identify predictors of in-hospital mortality. Stata 14.1 was used to conduct all analyses. RESULTS: A total of 408 patients, 204 with HAIs and 204 without HAIs were included in the study. In-hospital mortality was higher in patients with HAI (14.7% vs 7.8%, P = 0.028). Patients with HAI stayed an average of 8.3 days longer than controls (18.85 vs 10.59, P<0.001). The average direct medical costs for patients with HAI were 3033 Ethiopian birrs (ETB) higher than controls (4826 vs 1793, P<0.001). The presence of HAIs (AOR: 2.22, 95% CI: 1.13-4.39) and admission to intensive care units (AOR: 3.39, 95% CI: 1.55-7.40) were significant predictors of in-hospital mortality. CONCLUSION: HAIs have a significant impact on in-hospital mortality, the length of extra hospital stays, and extra costs for medical care. Patients admitted to intensive care units and those with HAIs were found to be significant predictors of in-hospital mortality. Interventions must be implemented to prevent HAIs, especially in patients admitted to intensive care units.

Phylogenetic Inference of the 2022 Highly Pathogenic H7N3 Avian Influenza Outbreak in Northern Mexico.

The Mexican lineage H7N3 highly pathogenic avian influenza virus (HPAIV) has persisted in Mexican poultry since its first isolation in 2012. To date, the detection of this virus has gradually expanded from the initial one state to 18 states in Mexico. Despite the HPAIV H7N3 outbreak occurring yearly, the transmission pathways have never been studied, disallowing the establishment of effective control measures. We used a phylogenetic approach to unravel the transmission pathways of 2022 H7N3 HPAIVs in the new outbreak areas in Northern Mexico. We present genetic data of H7N3 viruses produced from 18 poultry farms infected in the spring of 2022. Our results indicate that the virus responsible for the current outbreak in Northern Mexico evolved from the Mexican lineage H7N3 HPAIV discovered in 2012. In the current outbreak, we identified five clusters of infection with four noticeably different genetic backgrounds. It is a cluster IV-like virus that was transmitted into one northern state causing an outbreak, then spreading to another neighboring northern state, possibly via a human-mediated mechanical transmission mechanism. The long-distance transmission event highlights the necessity for the more rigorous enforcement of biosafety measures in outbreaks. Additionally, we examined the evolutionary processes shaping the viral genetic and antigenic diversities. It is imperative to enhance active surveillance to include birds, the environment, and humans to detect HPAI in domestic poultry at an earlier point and eliminate it.

A threat from both sides: Multiple introductions of genetically distinct H5 HPAI viruses into Canada via both East Asia-Australasia/Pacific and Atlantic flyways.

From 2016 to 2020, high pathogenicity avian influenza (HPAI) H5 viruses circulated in Asia, Europe, and Africa, causing waves of infections and the deaths of millions of wild and domestic birds and presenting a zoonotic risk. In late 2021, H5N1 HPAI viruses were isolated from poultry in Canada and also retrospectively from a great black-backed gull (Larus marinus), raising concerns that the spread of these viruses to North America was mediated by migratory wild bird populations. In February and April 2022, H5N1 HPAI viruses were isolated from a bald eagle (Haliaeetus leucocephalus) and broiler chickens in British Columbia, Canada. Phylogenetic analysis showed that the virus from bald eagle was genetically related to H5N1 HPAI virus isolated in Hokkaido, Japan, in January 2022. The virus identified from broiler chickens was a reassortant H5N1 HPAI virus with unique constellation genome segments containing PB2 and NP from North American lineage LPAI viruses, and the remaining gene segments were genetically related to the original Newfoundland-like H5N1 HPAI viruses detected in November and December 2021 in Canada. This is the first report of H5 HPAI viruses' introduction to North America from the Pacific and the North Atlantic-linked flyways and highlights the expanding risk of genetically distinct virus introductions from different geographical locations and the potential for local reassortment with both the American lineage LPAI viruses in wild birds and with both Asian-like and European-like H5 HPAI viruses. We also report the presence of some amino acid substitutions across each segment that might contribute to the replicative efficiency of these viruses in mammalian host, evade adaptive immunity, and pose a potential zoonotic risk.

Isolation and Characterization of Novel Reassortant Influenza A(H10N7) Virus in a Harbor Seal, British Columbia, Canada.

We isolated a novel reassortant influenza A(H10N7) virus from a harbor seal in British Columbia, Canada, that died from bronchointerstitial pneumonia. The virus had unique genome constellations involving lineages from North America and Eurasia and polymerase basic 2 segment D701N mutation, associated with adaptation to mammals.

Evolutionary Dynamics of Mexican Lineage H5N2 Avian Influenza Viruses.

We have demonstrated for the first time a comprehensive evolutionary analysis of the Mexican lineage H5N2 avian influenza virus (AIV) using complete genome sequences (n = 189), from its first isolation in 1993 until 2019. Our study showed that the Mexican lineage H5N2 AIV originated from the North American wild bird gene pool viruses around 1990 and is currently circulating in poultry populations of Mexico, the Dominican Republic, and Taiwan. Since the implementation of vaccination in 1995, the highly pathogenic AIV (HPAIV) H5N2 virus was eradicated from Mexican poultry in mid-1995. However, the low pathogenic AIV (LPAIV) H5N2 virus has continued to circulate in domestic poultry populations in Mexico, eventually evolving into five distinct clades. In the current study, we demonstrate that the evolution of Mexican lineage H5N2 AIVs involves gene reassortments and mutations gained over time. The current circulating Mexican lineage H5N2 AIVs are classified as LPAIV based on the amino acid sequences of the hemagglutinin (HA) protein cleavage site motif as well as the results of the intravenous pathogenicity index (IVPI). The immune pressure from vaccinations most likely has played a significant role in the positive selection of antigenic drift mutants within the Mexican H5N2 AIVs. Most of the identified substitutions in these viruses are located on the critical antigenic residues of the HA protein and as a result, might have contributed to vaccine failures. This study highlights and stresses the need for vaccine updates while emphasizing the importance of continued molecular monitoring of the HA protein for its antigenic changes compared to the vaccines used.

Comparative Susceptibility of Madin-Darby Canine Kidney (MDCK) Derived Cell Lines for Isolation of Swine Origin Influenza A Viruses from Different Clinical Specimens.

Madin-Darby canine kidney (MDCK) cells are commonly used for the isolation of mammalian influenza A viruses. The goal of this study was to compare the sensitivity and suitability of the original MDCK cell line in comparison with MDCK-derived cell lines, MDCK.2, MDCK SIAT-1 and MDCK-London for isolation of swine-origin influenza A viruses (IAV-S) from clinical specimens. One-hundred thirty clinical specimens collected from pigs in the form of nasal swabs, lung tissue and oral fluids that were positive by PCR for the presence of IAV-S RNA were inoculated in the cell cultures listed above. MDCK-SIAT1 cells yielded the highest proportion of positive IAV-S isolations from all specimen types. For nasal swabs, 58.62% of the specimens were IAV-S positive in MDCK-SIAT1 cells, followed by MDCK-London (36.21%), and conventional MDCK and MDCK.2 cells (27.5%). For lung specimens, 59.38% were IAV-S positive in MDCK-SIAT1 cells, followed by MDCK-London (40.63%), and conventional MDCK and MDCK.2 cells (18.75-31.25%). Oral fluids yielded the lowest number of positive virus isolation results, but MDCK-SIAT1 cells were still had the highest rate (35%) of IAV-S isolation, whereas the isolation rate in other cells ranged from 5-7.5%. Samples with lower IAV-S PCR cycle threshold (Ct) values were more suitable for culturing and isolation. The isolated IAV-S represented H1N1-ß, H1N2-α, H1N1pdm and H3N2 cluster IV and cluster IVB viruses. The result of the current study demonstrated the importance of using the most appropriate MDCK cells when isolating IAV-S from clinical samples.

Heterogeneity of Early Host Response to Infection with Four Low-Pathogenic H7 Viruses with a Different Evolutionary History in the Field.

Once low-pathogenic avian influenza viruses (LPAIVs) of the H5 and H7 subtypes from wild birds enter into poultry species, there is the possibility of them mutating into highly pathogenic avian influenza viruses (HPAIVs), resulting in severe epizootics with up to 100% mortality. This mutation from a LPAIV to HPAIV strain is the main cause of an AIV's major economic impact on poultry production. Although AIVs are inextricably linked to their hosts in their evolutionary history, the contribution of host-related factors in the emergence of HPAI viruses has only been marginally explored so far. In this study, transcriptomic sequencing of tracheal tissue from chickens infected with four distinct LP H7 viruses, characterized by a different history of pathogenicity evolution in the field, was implemented. Despite the inoculation of a normalized infectious dose of viruses belonging to the same subtype (H7) and pathotype (LPAI), the use of animals of the same age, sex and species as well as the identification of a comparable viral load in the target samples, the analyses revealed a heterogeneity in the gene expression profile in response to infection with each of the H7 viruses administered.

Outbreak of Rabbit Hemorrhagic Disease Virus 2 Infections, Ghana.

In September 2019, high mortality in commercial rabbits was reported in the Greater Accra Region of Ghana. Rabbit hemorrhagic disease virus 2 phylogenetically related to isolates from 2015-2017 outbreaks in the Netherlands was confirmed as the causative agent. The virus has not yet been detected in native rabbits in Ghana.

Evaluation of mobile real-time polymerase chain reaction tests for the detection of severe acute respiratory syndrome coronavirus 2.

The coronavirus disease 2019 (COVID-19) pandemic, caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), calls for prompt and accurate diagnosis and rapid turnaround time for test results to limit transmission. Here, we evaluated two independent molecular assays, the Biomeme SARS-CoV-2 test, and the Precision Biomonitoring TripleLock SARS-CoV-2 test on a field-deployable point-of-care real-time PCR instrument, Franklin three9, in combination with Biomeme M1 Sample Prep Cartridge Kit for RNA 2.0 (M1) manual extraction system for rapid, specific, and sensitive detection of SARS-COV-2 in cell culture, human, and animal clinical samples. The Biomeme SARS-CoV-2 assay, which simultaneously detects two viral targets, the orf1ab and S genes, and the Precision Biomonitoring TripleLock SARS-CoV-2 assay that targets the 5' untranslated region (5' UTR) and the envelope (E) gene of SARS-CoV-2 were highly sensitive and detected as low as 15 SARS-CoV-2 genome copies per reaction. In addition, the two assays were specific and showed no cross-reactivity with Middle Eastern respiratory syndrome coronavirus (MERS-CoV), infectious bronchitis virus (IBV), porcine epidemic diarrhea virus (PEDV), transmissible gastroenteritis (TGE) virus, and other common human respiratory viruses and bacterial pathogens. Also, both assays were highly reproducible across different operators and instruments. When used to test animal samples, both assays equally detected SARS-CoV-2 genetic materials in the swabs from SARS-CoV-2-infected hamsters. The M1 lysis buffer completely inactivated SARS-CoV-2 within 10 min at room temperature enabling safe handling of clinical samples. Collectively, these results show that the Biomeme and Precision Biomonitoring TripleLock SARS-CoV-2 mobile testing platforms could reliably and promptly detect SARS-CoV-2 in both human and animal clinical samples in approximately an hour and can be used in remote areas or health care settings not traditionally serviced by a microbiology laboratory.

Genetic and Antigenic Characterization of Avian Avulavirus Type 6 (AAvV-6) Circulating in Canadian Wild Birds (2005-2017).

We describe for the first time the genetic and antigenic characterization of 18 avian avulavirus type-6 viruses (AAvV-6) that were isolated from wild waterfowl in the Americas over the span of 12 years. Only one of the AAvV-6 viruses isolated failed to hemagglutinate chicken red blood cells. We were able to obtain full genome sequences of 16 and 2 fusion gene sequences from the remaining 2 isolates. This is more than double the number of full genome sequences available at the NCBI database. These AAvV-6 viruses phylogenetically grouped into the 2 existing AAvV-6 genotype subgroups indicating the existence of an intercontinental epidemiological link with other AAvV-6 viruses isolated from migratory waterfowl from different Eurasian countries. Antigenic maps made using HI assay data for these isolates showed that the two genetic groups were also antigenically distinct. An isolate representing each genotype was inoculated in specific pathogen free (SPF) chickens, however, no clinical symptoms were observed. A duplex fusion gene based real-time assay for the detection and genotyping of AAvV-6 to genotype 1 and 2 was developed. Using the developed assay, the viral shedding pattern in the infected chickens was examined. The chickens infected with both genotypes were able to shed the virus orally for about a week, however, no significant cloacal shedding was detected in chickens of both groups. Chickens in both groups developed detectable levels of anti-hemagglutinin antibodies 7 days after infection.

Susceptibility of turkeys, chickens and chicken embryos to SARS-CoV-2.

The susceptibility of turkeys, chickens and chicken embryos to SARS-CoV-2 was evaluated by experimental infection. Turkeys and chickens were inoculated using a combination of intranasal, oral and ocular routes. Both turkeys and chickens did not develop clinical disease or seroconvert following inoculation. Viral RNA was not detected in oral swabs, cloacal swabs or in tissues using quantitative real-time RT-PCR. In addition, chicken embryos were inoculated by various routes including the yolk sac, intravenous, chorioallantoic membrane and allantoic cavity. In all instances, chicken embryos failed to support replication of the virus. SARS-CoV-2 does not affect turkeys or chickens in the current genetic state and does not pose any potential risk to establish an infection in both species of domestic poultry.

Development of A recombinant nucleocapsid based indirect ELISA for the detection of antibodies to avian metapneumovirus subtypes, A, B, and C.

Nucleocapsid (N) protein is the most highly expressed of all avian metapneumovirus (aMPV) viral proteins and stimulates a substantial immune response in infected animals. Codon optimized recombinant N (rec-N) protein from aMPV subtypes A, B, and C were expressed using the baculoviral expression system in Trichoplusia ni (Tni) insect cells. A mixture of purified rec-N antigens from each subtype was used as a coating antigen and was evaluated in indirect ELISA (iELISA) to assess antibody response in serum samples collected from experimentally infected chickens and turkeys with different aMPV subtypes. Also, archived field serum samples that were collected from different poultry submissions were used. Receiver operating characteristic (ROC) analysis was performed using chicken and turkey serum samples that were confirmed by indirect fluorescent antibody (IFA) test for serostatus (positive n = 270, negative n = 610). The ROC analysis showed sensitivity and specificity of 97 % at a cut-off value of 0.25. The rec-N iELISA was compared with a commercial whole virus-based APV kit. The rec-N iELISA showed comparable results in detecting antibody response in aMPV infected chicken sera but was more sensitive in detecting early antibody response in aMPV infected turkey serum samples. Our results further confirm the presence of aMPV antibodies in Canadian domestic poultry populations. The developed aMPV-rec N iELISA offers a safe and valuable alternative to whole virus-based iELISA for serodiagnosis and seroepidemiological surveillance of the disease in domestic poultry.