Study shows MERS-CoV present in dromedary camels
Chantal Reusken, a researcher with the National Institute for Public Health and the Environment in Bilthoven, the Netherlands, and his colleagues gathered 349 blood serum samples from various livestock animals in multiple countries to test for MERS-CoV antibodies. The results of the study were announced on Thursday. It was the first reported animal serological study for MERS-CoV.
While MERS-CoV antibodies were not found in cows, sheep and goats from the Netherlands and Spain, the antibodies were found in all 50 serum samples taken from dromedary camels in the Oman. Antibodies for MERS-CoV were also found in 14 percent of serum samples taken from dromedary camels from the Canary Islands.
"The dromedary camels that we tested from the Middle East (Oman) were more often positive and had much higher levels of antibodies to MERS-CoV than the dromedary camels from Spain," the authors said. "The best way to explain this is that there is a MERS-CoV-like virus circulating in dromedary camels, but that the behavior of this virus in the Middle East is somehow different to that in Spain."
Recent research showed that the MERS-CoV can replicate in the cell lines of bats. Since the virus is not likely transmitting directly from bats to humans, given the shy and nocturnal habits of most bats, dromedary camels may be more likely candidates for transmission of the disease.
"As new human cases of MERS-CoV continue to emerge, without any clues about the sources of infection except for people who caught it from other patients, these new results suggest that dromedary camels may be one reservoir of the virus that is causing MERS-CoV in humans," the authors said. "Dromedary camels are a popular animal species in the Middle East, where they are used for racing, and also for meat and milk, so there are different types of contact of humans with these animals that could lead to transmission of a virus."
Reusken and his colleagues said future research efforts should focus on animal studies in the Middle East to find the virus that triggers MERS-CoV antibodies in dromedary camels.
In a linked comment to the study, Vincent Munster, a doctor with the U.S. National Institute of Allergy and Infectious Diseases' Rocky Mountain Laboratories, said that in the absence of treatment options for MERS-CoV, blocking animal-to-human transmission and human-to-human transmission could be the most cost-effective method to prevent further human fatalities.