Low #Prevalence of #SARS-CoV-2 in Farmed and Free-Ranging White-Tailed #Deer in #Florida

Source: Viruses, https://www.mdpi.com/1999-4915/16/12/1886

Abstract
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has been detected in multiple animal species, including white-tailed deer (WTD), raising concerns about zoonotic transmission, particularly in environments with frequent human interactions. To understand how human exposure influences SARS-CoV-2 infection in WTD, we compared infection and exposure prevalence between farmed and free-ranging deer populations in Florida. We also examined the timing and viral variants in WTD relative to those in Florida’s human population. Between 2020 and 2022, we collected respiratory swabs (N = 366), lung tissue (N = 245), retropharyngeal lymph nodes (N = 491), and serum specimens (N = 381) from 410 farmed and 524 free-ranging WTD. Specimens were analyzed using RT-qPCR for infection and serological assays for exposure. SARS-CoV-2 infection was detected in less than 1% of both northern Florida farmed (0.85%) and free-ranging (0.76%) WTD. No farmed deer possessed virus-neutralizing antibodies, while one free-ranging WTD tested positive for SARS-CoV-2 antibodies (3.45%). Viral sequences in infected WTD matched peaks in human cases and circulating variants, indicating human-to-deer spillover but at a lower frequency than reported elsewhere. Our findings suggest a reduced risk of SARS-CoV-2 spillover to WTD in northern Florida compared to other regions, highlighting the need for further research on transmission dynamics across North America.

____

#abstract #covid #COVID19 #deer #florida #health #research #sarsCov2 #serology #seroprevalence #USA #vaccine

Source: BioRxIV, https://www.biorxiv.org/content/10.1101/2024.11.06.622244v1

Abstract
The current situation with H5N1 highly pathogenic avian influenza virus (HPAI) is causing a worldwide concern due to multiple outbreaks in wild birds, poultry, and mammals. Moreover, multiple zoonotic infections in humans have been reported. Importantly, HPAI H5N1 viruses with genetic markers of adaptation to mammals have been detected. Together with HPAI H5N1, avian influenza viruses H7N9 (high and low pathogenic) stand out due to their high mortality rates in humans. This raises the question of how prepared we are serologically and whether seasonal vaccines are capable of inducing protective immunity against these influenza subtypes. An observational study was conducted in which sera from people born between years 1925-1967, 1968-1977, and 1978-1997 were collected before or after 28 days or 6 months post-vaccination with an inactivated seasonal influenza vaccine. Then, haemagglutination inhibition, viral neutralization, and immunoassays were performed to assess the basal protective immunity of the population as well as the ability of seasonal influenza vaccines to induce protective responses. Our results indicate that subtype-specific serological protection against H5N1 and H7N9 in the representative Spanish population evaluated was limited or nonexistent. However, seasonal vaccination was able to increase the antibody titers to protective levels in a moderate percentage of people, probably due to cross-reactive responses. These findings demonstrate the importance of vaccination and suggest that seasonal influenza vaccines could be used as a first line of defense against an eventual pandemic caused by avian influenza viruses, to be followed immediately by the use of more specific pandemic vaccines.

____

https://etidioh.wordpress.com/2024/11/09/are-we-serologically-prepared-against-an-avian-influenza-pandemic-and-could-seasonal-flu-vaccines-help-us/

#aH5n1 #aH7n9 #abstract #avianInfluenza #AVIANINFLUENZA #birdFlu #h5n1 #health #human #news #pandemicInfluenza #research #seasonalInfluenza #serology #vaccination

Source: US Centers for Disease Control and Prevention, MMWR Morbidity and Mortality Weekly Report, https://www.cdc.gov/mmwr/volumes/73/wr/mm7344a3.htm?s_cid=mm7344a3_e&ACSTrackingID=USCDC_921-DM140166&ACSTrackingLabel=This%20Week%20in%20MMWR%3A%20Vol.%2073%2C%20November%207%2C%202024&deliveryName=USCDC_921-DM140166

Summary

What is already known about this topic?

What is added by this report?

What are the implications for public health practice?

Abstract
Since April 2024, sporadic infections with highly pathogenic avian influenza (HPAI) A(H5) viruses have been detected among dairy farm workers in the United States. To date, infections have mostly been detected through worker monitoring, and have been mild despite the possibility of more severe illness. During June–August 2024, CDC collaborated with the Michigan Department of Health and Human Services and the Colorado Department of Public Health and Environment to implement cross-sectional serologic surveys to ascertain the prevalence of recent infection with HPAI A(H5) virus among dairy workers. In both states, a convenience sample of persons who work in dairies was interviewed, and blood specimens were collected. Among 115 persons, eight (7%; 95% CI = 3.6%–13.1%) had serologic evidence of recent infection with A(H5) virus; all reported milking cows or cleaning the milking parlor. Among persons with serologic evidence of infection, four recalled being ill around the time cows were ill; symptoms began before or within a few days of A(H5) virus detections among cows. This finding supports the need to identify and implement strategies to prevent transmission among dairy cattle to reduce worker exposures and for education and outreach to dairy workers concerning prevention, symptoms, and where to seek medical care if the workers develop symptoms. Timely identification of infected herds can support rapid initiation of monitoring, testing, and treatment for human illness, including mild illness, among exposed dairy workers.

____

https://etidioh.wordpress.com/2024/11/07/serologic-evidence-of-recent-infection-with-highly-pathogenic-avian-influenza-ah5-virus-among-dairy-workers-michigan-and-colorado-june-august-2024-7-of-workers-were-posi/

#aH5n1 #abstract #avianInfluenza #AVIANINFLUENZA #birdFlu #colorado #dairyCow #h5n1 #health #human #michigan #news #occupationalHealth #research #serology #USCDC #USA

#US #CDC #Report on #Missouri #H5N1 #Serology Testing

Source: US Centers for Disease Control and Prevention, Topline Summary of Findings In August 2024, healthcare providers in Missouri had a patient who had gastrointestinal symptoms with a history of chronic respiratory illness. The person was hospitalized and tested for multiple respiratory pathogens, and was positive for influenza A. They recovered from their illness and were discharged. Follow-up surveillance…

https://etidioh.wordpress.com/2024/10/24/us-cdc-report-on-missouri-h5n1-serology-testing/

Source: US Centers for Disease Control and Prevention, https://www.cdc.gov/bird-flu/spotlights/missouri-h5n1-serology-testing.html

Topline Summary of Findings

In August 2024, healthcare providers in Missouri had a patient who had gastrointestinal symptoms with a history of chronic respiratory illness.

The person was hospitalized and tested for multiple respiratory pathogens, and was positive for influenza A.

They recovered from their illness and were discharged.

Follow-up surveillance testing was conducted at the Missouri Department of Health and Senior Services Public Health Laboratory using polymerase chain reaction (PCR) that is part of routine national influenza surveillance. Testing found that the patient tested presumptive positive for avian influenza A(H5) (“H5 bird flu”). There was no history of exposure to infected animals or humans. The specimen was forwarded to CDC as part of routine protocol. CDC confirmed the specimen as H5N1 bird flu and this was reported as a case on September 6, 2024.

Missouri state and local officials performed a lengthy retrospective investigation of everyone who came into close contact with the patient and identified seven people (6 health care workers and one family member) who had symptoms that warranted additional investigation given their potential exposure to this patient.

CDC, in support of this investigation, conducted a series of tests on blood specimens from 6 of these people – and the original patient – to help identify signs of previous infection or exposure to H5N1 well after full resolution of their symptoms. This was not possible for the others, whose suggestive symptoms had completely resolved at the time of interview.

None of the results of this extensive testing and investigation support that human-to-human spread occurred.

The health care workers who were tested showed no signs of previous H5N1 infection. They were all “sero-negative.” This finding rules out person-to-person spread between the MO case patient and any of health care workers tested. The Missouri case and a household contact both had some evidence – though inconsistent – which suggested exposure to – or a previous infection with – H5N1 using these serologic tests.

To date, human-to-human spread of H5 bird flu has not been identified in the United States. CDC believes the immediate risk to the general public from H5N1 bird flu remains low, but people with exposure to infected animals are at higher risk of infection.

Following these tests, CDC continues to assess that the risk that someone who has not had contact with an infected animal will become infected with H5N1 remains low.

(…)

____

https://etidioh.wordpress.com/2024/10/24/us-cdc-report-on-missouri-h5n1-serology-testing/

#aH5n1 #avianInfluenza #clusterOfCases #human #missouri #serology #updates #USCDC #USA

Source: Journal of Virology, https://journals.asm.org/doi/abs/10.1128/jvi.00948-24?af=R

ABSTRACT
Antigenic assessments of SARS-CoV-2 variants inform decisions to update COVID-19 vaccines. Primary infection sera are often used for assessments, but such sera are rare due to population immunity from SARS-CoV-2 infections and COVID-19 vaccinations. Here, we show that neutralization titers and breadth of matched human and hamster pre-Omicron variant primary infection sera correlate well and generate similar antigenic maps. The hamster antigenic map shows modest antigenic drift among XBB sub-lineage variants, with JN.1 and BA.4/BA.5 variants within the XBB cluster, but with fivefold to sixfold antigenic differences between these variants and XBB.1.5. Compared to sera following only ancestral or bivalent COVID-19 vaccinations, or with post-vaccination infections, XBB.1.5 booster sera had the broadest neutralization against XBB sub-lineage variants, although a fivefold titer difference was still observed between JN.1 and XBB.1.5 variants. These findings suggest that antibody coverage of antigenically divergent JN.1 could be improved with a matched vaccine antigen.

____

https://etidioh.wordpress.com/2024/10/04/human-and-hamster-sera-correlate-well-in-identifying-antigenic-drift-among-sars-cov-2-variants-including-jn1/

#abstract #COVID19 #research #sarsCov2 #serology

Source: Journal of Virology, https://journals.asm.org/doi/full/10.1128/jvi.00689-24?af=R

Abstract

The high genetic diversity of influenza viruses means that traditional serological assays have too low throughput to measure serum antibody neutralization titers against all relevant strains. To overcome this challenge, we developed a sequencing-based neutralization assay that simultaneously measures titers against many viral strains using small serum volumes using a workflow similar to traditional neutralization assays. The key innovation is to incorporate unique nucleotide barcodes into the hemagglutinin (HA) genomic segment, and then pool viruses with numerous different barcoded HA variants and quantify the infectivity of all of them simultaneously using next-generation sequencing. With this approach, a single researcher performed the equivalent of 2,880 traditional neutralization assays (80 serum samples against 36 viral strains) in approximately 1 month. We applied the sequencing-based assay to quantify the impact of influenza vaccination on neutralization titers against recent human H1N1 strains for individuals who had or had not also received a vaccine in the previous year. We found that the viral strain specificities of the neutralizing antibodies elicited by vaccination vary among individuals and that vaccination induced a smaller increase in titers for individuals who had also received a vaccine the previous year—although the titers 6 months after vaccination were similar in individuals with and without the previous-year vaccination. We also identified a subset of individuals with low titers to a subclade of recent H1N1 even after vaccination. We provide an experimental protocol (https://doi.org/10.17504/protocols.io.kqdg3xdmpg25/v1) and computational pipeline (https://github.com/jbloomlab/seqneut-pipeline) for the sequencing-based neutralization assays to facilitate the use of this method by others.

https://etidioh.wordpress.com/2024/09/24/high-throughput-sequencing-based-neutralization-assay-reveals-how-repeated-vaccinations-impact-titers-to-recent-human-h1n1-influenza-strains/

#aH1n1 #abstract #h1n1pdm09 #research #seasonalInfluenza #serology #vaccine

2 more #poultry #workers in #Colorado infected with #H5N1 #birdflu: #CDC - Study in #Michigan suggests virus not causing silent infections in people, CBC: https://www.cbc.ca/news/health/h5n1-poultry-workers-1.7270025

Last month, the Michigan Department of Health and Human Services launched a {#serology} study of workers who were around cows sickened by the bird flu. The researchers drew blood from 35 people.