A team of international researchers may have finally confirmed what scientists have wondered since the SARS virus sparked a global pandemic in 2003: Where it comes from.
In a study published in Nature Wednesday, researchers revealed the "strongest evidence to date" that the virus responsible for Severe Acute Respiratory Syndrome originated in Chinese horseshoe bats. Though experts have suspected bats as the source of the SARS virus for several years, they were stumped by how the infection leapt from the nocturnal animals to humans.
In order to learn more about the original SARS virus, Chinese researchers took genetic samples from a colony of horseshoe bats in Kunming for a year. Partnering with researchers in Australia, Singapore and the United States, the team discovered at least seven distinct strains of a SARS-like coronavirus and were able to isolate a live form of the virus.
What they found next suggests the SARS virus did not need to be transferred to an intermediate host in order for it to infect humans.
Instead, as the team notes, direct bat-to-human transmission is "plausible" since the SARS-like virus sample is capable of binding directly to human cell receptors.
"Even though our team reported that bats are natural reservoirs of SARS-like coronaviruses in 2005, we have been searching for this missing link for 10 years, and finally we've found it," Dr. Zhengli Shi, co-senior author of the study, said in a written statement.
The findings present some serious concerns for public health control, especially in light of the recent reports of a SARS-like virus in the Middle East. Since there were several distinct strains of the SARS-like virus in a single group of horseshoe bats, it's likely that the viruses are common among bats in Asia, researchers concluded.
"Even worse, we don't know how lethal these viruses would be if such an outbreak erupted," co-author Peter Daszak, who also serves as president of the New York-based EcoHealth Alliance, said in the statement.
While the team was able to isolate a live virus, which would make developing a vaccine possible, other similar SARS-like strains that have yet to be evaluated could crop up. Daszak recommends that people be cautious during their interactions with bats.
"Let's give them the natural space for their habitat, conserve them, and avoid hunting and trading in bats -- this is good for conservation and good for our health," Daszak told the Agence France-Presse.