The source of the Middle East Respiratory Syndrome (MERS) has officially been linked a species of bats located in Saudi Arabia.
The virus is a 100% genetic match found in Eqyptian Tomb Bats, according to the report released by the Center of Disease Control and Prevention.
"There have been several reports of finding MERS-like viruses in animals. None were a genetic match. 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," W. Ian Lipkin, MD, director of the Center for Infection and Immunity and a co-author of the study, said in a news release.
The MERS virus was found in September of 2012, with 100 cases reported worldwide. However, 70 of the case are from Saudi Arabia. The cause of the virus was unknown until the recent study was published:
Over a six-week period during field expeditions in October 2012 and April 2013, the researchers collected more than 1,000 samples from seven bat species in regions where cases of MERS were identified in Bisha, Unaizah, and Riyadh. Extensive analysis was performed using polymerase chain reaction and DNA sequencing revealed the presence of a wide range of alpha and beta coronaviruses in up to a third of bat samples. One fecal sample from an Egyptian Tomb Bat (Taphozous perforatus) collected within a few kilometers of the first known MERS victim's home contained sequences of a virus identical to those recovered from the victim.
According to the news release, infection may have spread by infected aerosols or ingestion of contaminated food.
"There is no evidence of direct exposure to bats in the majority of human cases of MERS," Ziad Memish, MD, Deputy Minister of Health, Kingdom of Saudi Arabia, and lead author of the study, said in a news release. "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."
Researchers are continuing to look into the cause of the virus, and are investigating possible presence of MERS in camels, sheep, goats and cattle.
