OmniVira

H5N1 clade 2.3.4.4b dynamics in experimentally infected calves and cows.

Nico Joel Halwe1 Konner Cool2 Angele Breithaupt3 Jacob Schön1 Jessie D Trujillo2 Mohammed Nooruzzaman4 Taeyong Kwon2 Ann Kathrin Ahrens1 Tobias Britzke3 Chester D McDowell2 Ronja Piesche1 Gagandeep Singh2 Vinicius Pinho Dos Reis1 Sujan Kafle2 Anne Pohlmann1 Natasha N Gaudreault2 Björn Corleis5 Franco Matias Ferreyra6 Mariano Carossino7,8 Udeni B R Balasuriya7,8 Lisa Hensley9 Igor Morozov2 Lina M Covaleda4 Diego G Diel4 Lorenz Ulrich1 Donata Hoffmann1 Martin Beer10 Juergen A Richt11
Affiliations 11 institutions
  1. Institute of Diagnostic Virology, Friedrich-Loeffler-Institut, Greifswald - Insel Riems, Germany.
  2. Department of Diagnostic Medicine/Pathobiology, College of Veterinary Medicine, Kansas State University, Manhattan, KS, USA.
  3. Department of Experimental Animal Facilities and Biorisk Management, Friedrich-Loeffler-Institut, Greifswald - Insel Riems, Germany.
  4. Department of Population Medicine and Diagnostic Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY, USA.
  5. Institute of Immunology, Friedrich-Loeffler-Institut, Greifswald - Insel Riems, Germany.
  6. Veterinary Diagnostic Laboratory, College of Veterinary Medicine, Kansas State University, Manhattan, KS, USA.
  7. Louisiana Animal Disease Diagnostic Laboratory, School of Veterinary Medicine, Louisiana State University, Baton Rouge, LA, USA.
  8. Department of Pathobiological Sciences, School of Veterinary Medicine, Louisiana State University, Baton Rouge, LA, USA.
  9. Zoonotic and Emerging Disease Research Unit, National Bio and Agro-Defense Facility, Agricultural Research Service, United States Department of Agriculture, Manhattan, KS, USA.
  10. Institute of Diagnostic Virology, Friedrich-Loeffler-Institut, Greifswald - Insel Riems, Germany. [email protected].
  11. Department of Diagnostic Medicine/Pathobiology, College of Veterinary Medicine, Kansas State University, Manhattan, KS, USA. [email protected].
PMID39321846 DOI10.1038/s41586-024-08063-y Year2025 Journal Nature Languageeng Statusppublish

Abstract

In March 2024, highly pathogenic avian influenza virus (HPAIV) clade 2.3.4.4b H5N1 infections were reported in dairy cows in Texas, USA1. Rapid dissemination to more than 380 farms in 14 states followed2. Here we provide results of two independent clade 2.3.4.4b experimental infection studies evaluating the oronasal susceptibility to and transmission of a US H5N1 bovine isolate, genotype B3.13 (H5N1 B3.13), in calves, and the susceptibility of lactating cows following direct mammary gland inoculation of either H5N1 B3.13 or a current EU H5N1 wild bird isolate, genotype euDG (H5N1 euDG). Inoculation of the calves resulted in moderate nasal replication and shedding with no severe clinical signs or transmission to sentinel calves. In dairy cows, infection resulted in no nasal shedding, but severe acute infection of the mammary gland with necrotizing mastitis and high fever was observed for both H5N1 isolates. Milk production was rapidly and markedly reduced and the physical condition of the cows was severely compromised. Virus titres in milk rapidly peaked at 109 50% tissue culture infectious dose (TCID50) per ml, but systemic infection did not ensue. Notably, the adaptive mutation E627K emerged in the viral polymerase basic protein 2 (PB2) after intramammary replication of H5N1 euDG. Our data suggest that in addition to H5N1 B3.13, other HPAIV H5N1 strains have the potential to replicate in the udder of cows and that milk and milking procedures, rather than respiratory spread, are likely to be the primary routes of H5N1 transmission between cattle.

Supporting text Virus Host Location
Cattle Diseases 47 Influenza A Virus, H5N1 Subtype 300 Orthomyxoviridae Infections 228 Animals 1948 Cattle 126 Disease Susceptibility 21 Female 289 Genotype 137 Lactation 6 Mammary Glands, Animal 4 Milk 14 Nose 8 Texas 14 Virus Replication 191 Virus Shedding 51

Evidence records

6 total
Zoonotic Surveillance
4 records · 3 evidence types
Evidence type Virus Isolation
2 records
OVE8416 Virus Isolation
Key finding

Infectious H5N1 B3.13 virus was recovered from milk of experimentally infected dairy cows, reaching titres of 10^9 TCID50 per ml.

Virus
Influenza A virus H5N1
Host
domestic cattle Bos taurus Experimental system
Location
Not specified
Supporting text

In dairy cows, infection resulted in no nasal shedding, but severe acute infection of the mammary gland with necrotizing mastitis and high fever was observed for both H5N1 isolates. Virus titres in milk rapidly peaked at 10^9 50% tissue culture infectious dose (TCID50) per ml, but systemic infection did not ensue.

Sample type
milk
OVE8417 Virus Isolation
Key finding

Infectious H5N1 euDG virus was recovered from milk of experimentally infected dairy cows, reaching titres of 10^9 TCID50 per ml.

Virus
Influenza A virus H5N1
Host
domestic cattle Bos taurus Experimental system
Location
Not specified
Supporting text

In dairy cows, infection resulted in no nasal shedding, but severe acute infection of the mammary gland with necrotizing mastitis and high fever was observed for both H5N1 isolates. Virus titres in milk rapidly peaked at 10^9 50% tissue culture infectious dose (TCID50) per ml, but systemic infection did not ensue.

Sample type
milk
Evidence type Viral Detection
1 records
OVE8413 Viral Detection
Key finding

Moderate nasal replication and viral shedding of H5N1 B3.13 were detected in experimentally inoculated calves.

Virus
Influenza A virus H5N1
Host
domestic cattle Bos taurus Experimental system
Location
Not specified
Supporting text

Here we provide results of two independent clade 2.3.4.4b experimental infection studies evaluating the oronasal susceptibility to and transmission of a US H5N1 bovine isolate, genotype B3.13 (H5N1 B3.13), in calves. Inoculation of the calves resulted in moderate nasal replication and shedding with no severe clinical signs or transmission to sentinel calves.

Method
experimental inoculation | viral detection of shedding
Sample type
nasal samples
Evidence type Reservoir Ecology
1 records
OVE8419 Reservoir Ecology
Key finding

Milk and milking procedures, rather than respiratory spread, were identified as the main ecological routes of H5N1 transmission among cattle due to viral replication in the udder of cows.

Virus
Influenza A virus H5N1
Host
domestic cattle Bos taurus Natural host
Location
Not specified
Supporting text

Our data suggest that in addition to H5N1 B3.13, other HPAIV H5N1 strains have the potential to replicate in the udder of cows and that milk and milking procedures, rather than respiratory spread, are likely to be the primary routes of H5N1 transmission between cattle.

Method
experimental infection study
Sample type
milk | udder tissue
Experimental Infection
1 records · 1 evidence types
Evidence type Host Range Experiment
1 records
OVE8412 Host Range Experiment
Key finding

Lactating cows experimentally inoculated intramammarily with the H5N1 euDG genotype were susceptible, with intramammary replication and high virus titres in milk.

Virus
Influenza A virus H5N1
Host
domestic cattle Bos taurus Experimental system birds Aves Natural host
Location
Not specified
Supporting text

the susceptibility of lactating cows following direct mammary gland inoculation of either H5N1 B3.13 or a current EU H5N1 wild bird isolate, genotype euDG (H5N1 euDG). Infection resulted in no nasal shedding, but severe acute infection of the mammary gland with necrotizing mastitis and high fever was observed for both H5N1 isolates. Virus titres in milk rapidly peaked at 10^9 TCID50 per ml.

Method
direct mammary gland inoculation | virus titration in milk | pathology assessment | TCID50 quantification
Sample type
milk | mammary gland tissue
Experimental system
live animal intramammary gland inoculation challenge
Functional Mechanism
1 records · 1 evidence types
Evidence type Molecular Adaptation
1 records
OVE8418 Molecular Adaptation
Key finding

After replication of H5N1 euDG in the bovine mammary gland, the adaptive polymerase mutation PB2 E627K emerged, indicating host-specific molecular adaptation.

Virus
Influenza A virus H5N1
Host
Not specified
Location
Not specified
Supporting text

Notably, the adaptive mutation E627K emerged in the viral polymerase basic protein 2 (PB2) after intramammary replication of H5N1 euDG.

Genes or proteins
PB2
Mutations
E627K
Mechanism types
replication adaptation | host-range expansion