In a new report in Emerging Infectious Diseases — a journal of the U.S. Centers for Disease Control and Prevention — an international team of researchers said a 100 percent genetic match for MERS was discovered in an insect-eating bat in close proximity to the first known case of the disease in Saudi Arabia.
 

The discovery points to the likely animal origin for the disease, according to the team investigators from Columbia University's Mailman School of Public Health, the EcoHealth Alliance, and the Ministry of Health of the Kingdom of Saudi Arabia.
 

"There have been several reports of finding MERS-like viruses in animals. None were a genetic match," said W. Ian Lipkin, M.D. "In this case we have a virus in an animal that is identical in sequence to the virus found in the first human case. Importantly, it's coming from the vicinity of that first case."
 

MERS was first identified last September and continues to spread. Close to 100 cases have been reported worldwide, 70 from Saudi Arabia. To identify the bat as the source of the virus, investigators spent six weeks conducting field expeditions and collected more than 1,000 samples from seven bat species in regions where cases of MERS were identified in Bisha, Unaizah, and Riyadh.
 

Bats are known to carry viruses that can cause human disease including rabies, Hendra, Nipah, Marburg, and SARS. In some instances the infection may spread directly from bats to humans, but it can also occur as a result of inhaling viral particles, eating contaminated food, or through another animal that can pass the virus from bats to humans.
 

"There is no evidence of direct exposure to bats in the majority of human cases of MERS," said Ziad Memish, M.D., Deputy Minister of Health, Kingdom of Saudi Arabia. "Given that human-to-human transmission is inefficient, we speculate that an as-yet-to-be determined intermediate host plays a critical role in human disease."
 

In the coming days, the group plans to report on results of its investigation into the possible presence of MERS in camels, sheep, goats, and cattle.