On September 28, three cats of a confirmed case of new coronary pneumonia in Nangang District, Harbin were euthanized because of positive nucleic acid. On September 29, an expert told The Paper that the current cat infection incident in Harbin is likely to be an occasional infection after pets are exposed to the new coronavirus, and pets will continue to pollute the environment and cause continued transmission.
Should "euthanize cats with nucleic acid positive" be "also known as euthanasia" is also a focus of attention from netizens. How to deal with pets after they are infected with the new coronavirus? Is there any other way to keep your pets around besides euthanasia? In response to the above issues, The Paper interviewed Lu Xuexin, an expert from the Institute of Virology Prevention and Control of the Chinese Center for Disease Control and Prevention, to explain the doubts.
Cats are very susceptible to the new coronavirus
At noon on September 28, a confirmed case of new coronavirus in Harbin posted on Weibo that he was a confirmed patient and was actively cooperating with the treatment in the hospital, and no symptoms will be cured soon. But her community notified her that because the staff tested her three cats for nucleic acid and the result was positive, all three cats were euthanized.
According to the Beijing News on the 28th, on September 21, the patient was isolated due to a confirmed infection with COVID-19. During her treatment in the hospital, she equipped the cat with enough water and food, and community staff regularly came to her home to help take care of her. Community staff entered her home three times to test her living environment, and also took anal swab samples for three cats. Previously, the local animal epidemic prevention department had performed two anal swab tests on the cat, and the test results were all positive.
In fact, there have been many reports of animals being infected with the new coronavirus. The three cats with positive nucleic acid tests in Harbin are not the first.
The infections of these animals are mostly discovered through environmental monitoring or traceability of the new coronavirus. By conducting nucleic acid testing of the new coronavirus for nasopharyngeal swabs or excrements of animals, it is confirmed that the new coronavirus is positive.
Previously, the British magazine Nature website reported that when researchers from the US Department of Agriculture conducted a study on the serum samples of some white-tailed deer in the northeastern United States, they found that one-third of the sampled white-tailed deer had new coronavirus-related antibodies in their bodies, indicating that they had been infected with the new coronavirus.
The latest data from the US Department of Agriculture shows that as of now, there are nearly 300 confirmed cases of new crown in the United States, among which the top three animals in the number of confirmed cases are cats, dogs and tigers.
On March 31 last year, Academician Chen Hualan from the Harbin Veterinary Research Institute of the Chinese Academy of Agricultural Sciences and the National Center for Animal Disease Prevention and Control of the Chinese Academy of Agricultural Sciences and others published a related research article "Susceptibility of ferrets, cats, dogs, and different domestic animals to SARS-coronavirus-2" in the preprint bioRxiv. This article systematically studied ferrets, cats, dogs, ducks, and pigs and other animals vaccinated with the new coronavirus. They found that ferrets and cats are very susceptible to the new coronavirus, and dogs are less susceptible to the dogs, while livestock, including pigs, chickens and ducks, are not sensitive to the virus.
"At present, sufficient data has not been accumulated about the new coronavirus, and it is not possible to confirm whether the new coronavirus can be transmitted circulating between humans and animals. However, in the current cat infection incident in Harbin, it is very likely that the occasional infection of pets after they are exposed to the new coronavirus. Pets will continue to pollute the environment and continue to cause transmission." Lu Xuexin, an expert from the Institute of Virology Prevention and Control of the Chinese Center for Disease Control and Prevention, told The Paper.
Virals in animals need to accumulate enough mutations to spread to humans
Lu Xuexin believes that there are two main possibilities for the discovery of new coronavirus in animal groups under natural conditions. One is the continuous transmission of infection among animals, and the other is the occasional infection caused by surrounding environment pollution. In the former case, some types of viruses can be transmitted circulating between humans and animals, such as rabies virus, while the other viruses have species limitations and require sufficient mutations to spread to humans.
It was confirmed at the epidemic press conference held in Harbin that the virus that caused the local epidemic in Harbin this time is the Delta mutant strain. The delta mutant strain of the new coronavirus is more contagious. Will it be more likely to cause circulating transmission between humans and animals?
Lu Xuexin told The Paper that according to current virus research, there are already coronaviruses of their own species in animals such as cats and dogs. Delta's is more adaptive mutant strains after it spreads from animals to humans, which are more adaptable to humans than to animals.
According to Jiupai News on September 28, the community staff of the confirmed case responded to the matter that cats are different from humans. There is no place to treat cats. If the cats are not treated, the room is all positive, so the patient cannot come back, and the person in the unit where the patient is located cannot come back. There is no scientific conclusion yet on whether cats can cause human infection. A positive nucleic acid test for cats indicates that there is a possibility of virus transmission.
During the virus epidemic investigation and tracing process, are pets included? Lu Xuexin said that pet monitoring has not been included in the norms in the epidemic investigation. Many reported cases have proved that pet infection is present. The next step should be to continue to conduct research and judgment and include this method in the epidemiological investigation and tracing.
Lack of management measures for animals after they are infected with the new coronavirus
On the evening of September 28, the patient posted on Weibo again saying that the cat is "dead", and thanks everyone for speaking out for her.
The euthanasia of cats infected with the new coronavirus is currently the law that can be based on is Article 42 of the "Law of the People's Republic of China on the Prevention and Control of Infectious Diseases". This article clearly states that when an infectious disease breaks out or spreads, local people's governments at or above the county level shall immediately organize forces to prevent and control according to the prevention and control plan, and cut off the transmission route of infectious diseases. If necessary, the following emergency measures may be taken and announced after the decision of the people's government at the next level, including the control or culling of infected wild animals, livestock and poultry..
But under what circumstances does pet cats perform euthanasia? Who will execute it? Are there any other measures? my country currently has no management measures for animals after they are infected with the new coronavirus.
"Due to the complexity and diversity of animals and pets, the formulation of this detailed rules is extremely challenging." Lu Xuexin said that the epidemic prevention and control work should be carried out under the principle of comprehensively measuring the control of humans as the main body, and the prevention and control of animals should be carried out under the principle of protecting animal welfare as much as possible.
In other countries, there will be more operating guidelines for pets infected with the new coronavirus. The US CDC has stated in the "Guidelines for the Prevention and Control of Temporary Infections in Treating Companion Animals During COVID-19 Response" released by the official website (hereinafter referred to as the "Guidelines") that if the pet owner currently has respiratory symptoms or is suspected or has confirmed the new coronavirus, it is not recommended to visit a veterinary clinic. Consider whether telemedicine consultation is appropriate. If possible, healthy friends or family members from outside the family should bring the animals to the veterinary clinic. The clinic should take all appropriate precautions to minimize contact with the person who brings the animals to the clinic. If an animal is in an emergency, the animal should not be taken into consideration.
The above "Guidelines" provide detailed suggestions for pets that confirm positive for the new coronavirus, home isolation and veterinary clinics. For example, veterinary clinics or hospitals that care for sick pets that test positive for the new coronavirus should have rooms that can isolate the animals of the new coronavirus positive for the new coronavirus from other patient groups.
The centralized isolation of infected pets and the feasibility of pets being vaccinated with the new crown vaccine is not very feasible
In the Weibo posts of confirmed patients in Harbin, many netizens have put forward many suggestions on how to deal with pets infected with the new crown virus, including centralized isolation of infected pets and vaccinating pets with the new crown vaccine.
However, in Lu Xuexin's view, it is not feasible to centrally isolate infected pets.
"It is uncertain whether an animal will develop after being infected with the new coronavirus. It may be carried for a long time, or it may be transiently infected. These are difficult to guide isolation measures. In addition, there are diverse species of animals and different habits. The contact and communication between animal groups or different animals has caused many loopholes in management, and unified management is too difficult." Lu Xuexin explained that if an infection occurs, pet owners can be urged to isolate the animals and prevent transmission. Large-scale isolation is not feasible.
Like the prevention of rabies, will pets need to be vaccinated with the new crown vaccine in the future? Lu Xuexin said that with the development and changes of the new crown epidemic, the new crown virus has been mutating and becoming more complex and severe. At present, it should be better to vaccinate people as soon as possible and establish an immune barrier.
Lu Xuexin believes that vaccination of animal new crown vaccine is only a possible way of prevention and control, but from a scientific point of view, it will not play a role in the current prevention and control of the new crown.