Porcine deltacoronavirus: potential for cross-species transmission?
Researchers have found that Porcine deltacoronavirus (PDCoV) efficiently infects cultured cells of other species, including humans and chickens. The discovery raises concerns about the potential for cross-species transmission.
Porcine deltacoronavirus was first identified in 2012 in pigs in China, but it was not associated with disease. It was first detected in the United States in 2014 during a diarrhoea outbreak in Ohio pigs and has since been detected in various countries. Young, infected pigs experience acute diarrhoea and vomiting. The disease can be fatal.
“Before it was found in pigs – including in the Ohio outbreak – it had only been found in various birds,” said study senior author Linda Saif, an investigator in Ohio State’s Food Animal Health Research Program at the Ohio Agricultural Research and Development Center (OARDC).
“We’re very concerned about emerging coronaviruses and worry about the harm they can do to animals and their potential to jump to humans,” said Saif, a distinguished university professor of veterinary preventive medicine.
Emergence of the new virus is concerning veterinary and public-health experts because of its similarity to the life-threating viruses responsible for SARS (severe acute respiratory syndrome) and MERS (Middle East respiratory syndrome) outbreaks.
The potential for a virus to jump from one species to another is highly dependent on its ability to bind to receptors on the cells of the animal or human, said lead researcher Scott Kenney, an assistant professor of veterinary preventive medicine based in the Food Animal Health Research Program at OARDC.
This study looked at a particular cellular receptor called aminopeptidase N that the researchers suspected might be involved.
“We know from other coronaviruses that these receptors on the cells are used and that they’re found in the respiratory and digestive tracts of a number of different animals,” Kenney said. “Now we know that this new virus could go into cells of different species, including humans.”
Saif said it’s important to recognize that, for now, the only known infection in humans and other species is in the laboratory, using cultured cells. Their investigation confirmed that the virus could bind to the receptor in pigs, which was not a big surprise. But it also was able to bind to the receptor in human cells, and to cells from cats and chickens.
“From that point, it’s just a matter of whether it can replicate within the cells and cause disease in those animals and humans,” Kenney said.
Added Saif, “This doesn’t prove that this virus can infect and cause disease in these other species, but that’s something we obviously want to know.”
She said the next step in understanding this virus and its potential for human infection will be a study looking for antibodies in the blood that would serve as evidence that the pig virus has already infected people.
“We now know for sure that porcine deltacoronavirus can bind to and enter cells of humans and birds. Our next step is to look at susceptibility – can sick pigs transmit their virus to chickens, or vice versa, and to humans?” Saif said.
Article: Broad receptor engagement of an emerging global coronavirus may potentiate its diverse cross-species transmissibility by Wentao Li, Ruben J. G. Hulswit, Scott P. Kenney, Ivy Widjaja, Kwonil Jung, Moyasar A. Alhamo, Brenda van Dieren, Frank J. M. van Kuppeveld, Linda J. Saif, and Berend-Jan Bosch, published in PNAS, online 14 May 2018, doi: 10.1073/pnas.1802879115
[SOURCE: THE OHIO STATE UNIVERSITY]