Survey of fur-farmed animals reveals 125 viruses, including new and potentially leaky ones

Animals farmed for their fur, including raccoon dogs, foxes, minks and muskrats, may be important reservoirs and sources of emerging viruses, including those that are at high risk of infecting people, wildlife and livestock, Chinese researchers say. Reported yesterday Nature.

Researchers from the Shanghai Institute of Infectious Diseases and Biosafety led the analysis of metagenomic mRNA from 697 intestinal, lung and liver samples from 461 animals. (412 from fur and livestock farms, 49 from the wild) Deaths caused by the infection were discovered across China.

“Cross-species transmission of viruses from animals to humans can drive infectious disease outbreaks and sometimes lead to global pandemics,” the study authors wrote. “Because overlap between wild animals and humans is often limited, secondary contact with livestock may be a route by which zoonotic viruses can be transmitted to humans.”

However, current virus research is biased towards domestic animals such as pigs. “Importantly, fur animals such as foxes, civets and mink have been suggested as potential hosts for a variety of human viruses, including influenza A viruses (IAVs), SARS-CoV and SARS-CoV-220-23, and an outbreak of H5N1 IAV has recently been reported in farmed mink in Europe,” the researchers added.

39 types of viruses that may be leaked

The team identified 125 viruses, including 36 new (previously uncharacterized) and 39 with a high potential risk of interspecies transmission, including to humans. Most fur-farming animals harbored between 2 and 23 viruses associated with vertebrates.

In particular, 19 potentially high-risk viruses were detected in Shandong province, which has a large number of fur animal farms.

Sixty percent of the viruses expanded their known host range, including seven coronaviruses found in 66 fur-farming animals. The team noted that a novel canine respiratory coronavirus infected raccoon dogs and that the bat coronavirus HKU5 spread to minks, whose lungs contained high amounts of the coronavirus.

Three IAV subtypes (H1N2, H5N6, and H6N2) were detected in the lungs of guinea pigs, minks, and muskrats, respectively. Guinea pigs also harbored several zoonotic viruses that can be transmitted between animals and humans, including Japanese encephalitis virus and mammalian orthoreovirus.

“Most of the potentially high-risk viruses (n = 29) were collected in eastern China, with a detection rate of 40.5%,” the researchers wrote. “It is particularly noteworthy that 19 potentially high-risk viruses were detected in Shandong Province, which has a large number of fur animal farms.”

“An important transmission hub”

Viruses that showed evidence of frequent host jumping included 11 viruses already identified in humans, 15 viruses not identified in humans but identified in at least two mammalian taxa, and 13 potentially novel high-risk viruses.

Among the animals studied, raccoon dogs and minks were found to carry the highest potential risk of the virus, followed by Guinea pigs, rabbits, arctic foxes. Coronaviridae and Paramyxoviridae viruses commonly infect multiple animal species., and Sedoreoviridae viruses.

These data also highlight the potential transmission of viruses between farmed and wild animals, and from humans to farmed animals, indicating that fur farming represents an important hub for the transmission of viral zoonotic diseases.

“Of particular concern is Apistrellas Bat coronavirus HKU5-like virus (subgenus Melbecovirus) was detected in the lungs and intestines of two farmed mink on a single farm associated with a pneumonia outbreak, the authors wrote. [coronaviruses] It forms a relatively closely related lineage to viruses previously reported only in bats, where it has a history of recombination.”

In lung samples, the most abundant viruses were from the Paramyxoviridae, Coronaviridae, and Caliciviridae families, whereas in the intestine, the most abundant viruses were from the Coronaviridae, Sedreoviridae, and Astroviridae families.

“These data also highlight the potential transmission of viruses between farmed and wild animals, and from humans to farmed animals, indicating that fur farming represents an important hub for the transmission of viral zoonotic diseases,” the researchers wrote.

The team called for more extensive and regular monitoring of fur-farmed animals to identify potential routes of virus transmission between species and flag viruses that could infect humans, wildlife or livestock.