There have been concerns since the pandemic on how badly the coronavirus affects people. Factors considered include age, underlying illnesses, weight, and a variety of other variables. But what about coronavirus infection among other mammals?

As all existing data indicates that SARS-CoV-2 is a zoonotic disease, one that spreads from animals to humans, as the World Health Organisation (WHO) reports, concerns have also been posed regarding the possible effects of Covid-19 on domesticated pets as well as their human owners.

On 30 November, it was confirmed that at the same period that Johnson was admitted to intensive care, Boris Johnson's dog Dilyn, who resides at 10 Downing Street with the PM and his fiancé Carrie Symonds, 32, was assumed to have acquired the disease.

What do we feel about getting COVID-19 for pets? And is there any proof that this is spreading between pets and humans?

Are pets having the coronavirus?

It is "rare" for an animal to transmit coronavirus, according to official UK government advice. And if it happens, it says, "[animals] appear to have only minor signs and heal within a couple of days."

But it insists that there is no evidence" that the virus spreads between pets or that pets, except in the same household, may spread the virus to humans.

Are there examples of coronavirus infections in pets?

A pet dog in Hong Kong screened 'weak positive' for coronavirus in February and was placed into quarantine. The country's Department of Agriculture, Fisheries and Conservation (AFCD) reported that multiple testing indicated the dog had a "low level" of the virus.

The puppy, a Pomeranian, had not displayed any signs of the disease but its trainer was reported as being afflicted with Covid-19.

A month later, on 31 March, experts say a cat acquired coronavirus in Belgium, but the country's health authorities claimed that it was a "isolated case" and not a "the rule."

The UK saw its first reported case of coronavirus in a pet on 27 July. In the UK, the untreated cat was screened for the virus on 22 July at a laboratory in Weybridge, Surrey.

The animal had shown signs of a respiratory infection, with a nasal discharge and some shortness of breath," Downing Street said. Again, it was not an indication of severe illness in dogs, medical experts said.

But for certain pets afflicted with Covid-19, there have been serious findings. On 31 July, after apparently dealing with signs that could be common to many human sufferers of the infection, the first dog to test positive for Covid-19 in the US died.

Buddy, New York's seven-year-old German shepherd, had been sick since April, at the same time his trainer, Robert Mahoney, had been healing from Covid-19. Since experiencing long-term health complications as a consequence, the puppy was finally euthanized.

What do experts say about transmission between animals and humans?

Christine Middlemiss, chief veterinary officer, affirmed that it was very rare' for a cat to have acquired the virus until the UK saw its first reported pet case in July.

Yvonne Doyle, Public Health England's medical officer, said This is the first case of a positive domestic cat test in the UK for Covid-19, but it should not be a cause for alarm." The research into this event indicates that, and not the other way around the virus was transmitted from humans to livestock.

A paper published by researchers from University College London (UCL) in The Lancet Microbe on June 19 said further study was required on domesticated animals, including pet cats and dogs, that are susceptible to Covid-19.

They related to the finding of the virus in mink farms, where the animals were culled by outbreaks of Covid-19.

About 10 million minks have been killed to date by Denmark, the world's biggest exporter of mink fur, after discovering that the virus infected the species and believing that variant forms of the virus might be spread to wild animals.

Ireland announced on 20 November that it would kill 120,000 of the animals in an offer to escape the same situation as Denmark.

Meanwhile, researchers at the Centre for Genomic Control (CRG) in Barcelona found that humans, ferrets, cats, civets, and dogs are the most vulnerable animals to SARS-CoV-2 infection.

The results published in PLOS Computational Biology showed that, relative to humans, ducks, rats, rabbits, pigs, and chickens have little or no vulnerability to infection.

"Knowing which animals are susceptible to SARS-CoV-2 helps us prevent building up animal reservoirs from which the coronavirus can re-emerge at a later date," says Luis Serrano, ICREA Research Professor, Director of the CRG and senior author of the study.

"Though we also find a potential susceptibility to infection by cats, they don't co-exist with humans in the same conditions as other animals, which may explain why so far there are no known cases of people being infected by their pets," adds Dr. Serrano.

How do you reduce the risk of pets spreading?

The government says the safest way to ensure that you minimize all the risks of spreading the virus to your pet is to: wash your hands. It also urged the people to avoid hugging or cuddling after every interaction with your pet and do not eat food with them if you are self-isolating.

The World Health Organization says: "It is still a safe practice to wash your hands following interaction with pets with soap and water. This protects you against numerous common bacteria that may spread between pets and humans, such as E.coli and Salmonella.

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