When the Covid-19 pandemic struck, Professor Gregory Gray of the Global Health Institute at Duke University commissioned a graduate student from his lab to develop a cross-species coronavirus test to help prevent the next disaster.
The idea was to deploy the tool, once its accuracy has been validated, to look back on test samples from human patients to look for signs of coronavirus that could have started crossing animals.
The findings of Gray and his colleague, published Thursday in Clinical Infectious Diseases, showed that a canine coronavirus was present in a group of patients mostly children admitted to hospital with pneumonia in Malaysia in 2017 and 2018.
The team suspects the dog virus caused their illness, rather than just being present in patients’ airways – but cannot conclusively prove it.
Given the genetic makeup of the virus, it is unlikely that it is currently circulating among humans.
“What we’re advocating… is a greater application of pan-species diagnostics to find five different viral families that we think are the most problematic for causing epidemics in humans,” Gray told AFP.
Coronaviruses have been under-studied for many years because they were primarily associated with the common cold.
This changed after the SARS and MERS epidemics of 2002 and 2012, which caused civets and camels respectively.
Most scientists believe that the SARS-CoV-2 virus that causes Covid also has a zoonotic origin.
Gray asked Lishan Xiu, a Chinese doctoral student and researcher, to do a pan-species test for coronavirus, which he did by finding where the genetic sequences of different members of this family aligned.
They used the tool on nasal swab tests taken from pneumonia patients at hospital in Sarawak, Malaysia, and found that eight of the 301 samples appeared to have canine virus.
– ‘We miss the boat’ –
The discovery was surprising and to confirm it, they teamed up with leading virologist Anastasia Vlasova from Ohio State University, who was able to further develop the virus and sequence its entire genome.
From there, they determined that the virus, which they named CCoV-HuPn-2018, was primarily of canine origin, but it also contained feline and porcine components.
# photo1 It has shown mutations consistent with adaptation to human-to-human transmission, but it’s unclear how long that evolution might take – maybe decades, maybe never, Gray said.
All of the patients recovered from their pneumonia and were discharged home.
“But being admitted with pneumonia usually means you’re sick enough, the clinician is worried about you,” Gray added.
The fact that the team was able to detect the canine virus in humans in what was essentially a small pilot study, along with recent similar findings from other research groups, could point to a much larger problem, he said. -He underlines.
“We’re missing the boat here,” Gray said.
“If we put in place surveillance of hog, poultry and cattle workers, we will be amazed at how challenged their immune systems are.
“That doesn’t mean they’re going to be the game that lights up the next pandemic, but it would be a good resource to study. “
© 2021 AFP