By Natasha Khan
The deadly coronavirus linked to the Middle East was detected in three-quarters of samples taken from camels across Saudi Arabia, showing it’s widespread in the country and suggesting a way to control transmission.
Antibodies to the Middle East Respiratory Syndrome coronavirus, indicating past infection, were found in 74 percent of blood samples from more than 200 dromedary camels across the nation, a study published today in the microbiology journal mBio found. Nasal and rectal specimens showed genetic sequences of MERS-CoV from active infection in camels matched those in humans.
This survey is the first to show the spread of the pathogen across the biggest Arab economy following studies with smaller samples suggesting camels as a potential source of the virus that’s killed 79 people. While it remains unknown how humans contract the disease, the results highlight the importance of investigating camels’ role in transmission to people.
“What we know now is that camels carry the same MERS virus that infects humans,” Thomas Briese, associate director of Columbia University’s Center for Infection and Immunity and a co-author of the study, said in a statement. That “indicates that they have the potential to transmit the virus directly to humans,” he said.
There have been 182 laboratory-confirmed cases of infections with MERS-CoV including 79 deaths since September 2012, the World Health Organization said Feb. 7.
Countries affected include Jordan, Kuwait, Oman, Qatar, Saudi Arabia, the United Arab Emirates, Tunisia, France, Germany, Italy and the U.K., the Geneva-based WHO said. All cases have a link to the Middle East.
The virus is likely spread via airborne transmission between camels, given that it was more evident in nasal samples, the scientists said. No evidence of MERS-CoV was seen in a similar survey of sheep and goats.
MERS-CoV has been carried by Saudi Arabian camels for more than 20 years, based on blood serum samples dating back to 1992, according to the study. Human cases of the disease may have been around longer than previously thought, and prior to 2012 may have been generically labeled as “unexplained respiratory disease,” the researchers wrote.
The study was reported by a team of scientists from New York-based Columbia University and EcoHealth Alliance, Riyadh-based King Saud University, and the U.S. National Institute of Allergy and Infectious Diseases.
Previous studies have shown bats to be a source of the virus. Subsequent research has focused on camels as intermediate hosts, given humans’ limited contact with bats.