A new strain of coronavirus which originated in dogs is infecting children, new research suggests.

A study of Clinical Infectious Diseases in the US shows that coronavirus can be transmitted to humans from domestic pets, sparking concerns among scientists of further health crises in the future.

Study Co author Dr Anastasia Vlasova, of The Ohio State University, said: "At this point, we don't see any reasons to expect another pandemic from this virus.

“But I can't say that’s never going to be a concern."

Linked to breathing difficulties

The new disease evolved from a coronavirus that affects dogs to infect humans, and may contribute to respiratory symptoms.

Analysis found that the virus may contribute to respiratory symptoms after some participants in the study suffered with breathing difficulties, while one young patient developed pneumonia.

Project leader Professor Gregory Gray, of Duke University, North Carolina, analysed the archived nasal swabs of 301 people treated in a hospital in Sarawak in East Malaysia in 2018.

Eight of these patients, all but one of them children, were found to have been infected with the new coronavirus, named CCoV-HuPn-2018, with one of the patients aged just five and a half months old.

All eight patients recovered from the virus and were discharged after four to six days, following oxygen therapy to help them breathe.

The US research team identified the novel canine coronavirus using a molecular diagnostic tool that they created last year to detect Covid-19.

Dr Vlasova grew the virus in her lab from one of the clinical specimens, which came from a child, and by reconstructing its genome, the team were able to confirm the canine coronavirus.

However, it is not yet clear if the virus poses a serious threat, but researchers are concerned animal to human infections will become more frequent.

Prof Gray said: "How common this virus is, and whether it can be transmitted efficiently from dogs to humans or between humans, nobody knows.

"What is more important is these coronaviruses are likely spilling over to humans from animals much more frequently than we know.

"We are missing them because most hospital diagnostic tests only pick up known human coronaviruses."

"We need to conduct such virus discovery work among people with pneumonia and also among people who have intense exposure to animals so that we get early warning of a new virus which may become a future pandemic virus."

The researchers stressed that better surveillance of areas where animals and humans intersect are needed to help mitigate the threat of outbreaks in the future.

Dr Gray added: “If we really want to mitigate the threat, we need better surveillance where humans and animals intersect, and among people who are sick enough to get hospitalised for novel viruses.

“Diagnostic tools like his have the potential to identify other viruses new to humans before they can cause a pandemic.

"These pathogens don't just cause a pandemic overnight, it takes many years for them to adapt to the human immune system and cause infection, and then to become efficient in human-to-human transmission.

“We need to look for these pathogens and detect them early."

Research ongoing

The researchers plan to study the new virus further to determine how harmful it is, or could become, to humans.

At the moment, it is unknown if the virus can be passed from person to person, or how well the human immune system can fight it off.

Dr Vlasova said: "We don’t really have evidence right now that this virus can cause severe illness in adults."

She noted that only one of the infected patients was an adult, adding: “I cannot rule out the possibility that at some point this new coronavirus will become a prevalent human pathogen.

“Once a coronavirus is able to infect a human, all bets are off."

When a virus alters its genetic makeup enough to go from infecting an animal to people, a combination of factors determine how well it replicates and spreads.

It must first enter the human body and recognise something on the surface of the cells, then bind to them. Around half of the genes of the canine coronavirus are similar to those of Covid-19.

The virus causes different symptoms in dogs, including gastrointestinal problems, while infected people experience a respiratory illness.

The potential threat posed by the viruses of dogs or cats, which also suffer illnesses from coronaviruses, has not been studied widely, but researchers are now calling for better monitoring

Dr Vlasova added: “Monitoring animal viruses is a way of protecting public health.

"We primarily put the emphasis on studying emerging disease in humans – not animals. That is a big flaw in the current approach."