MERS, or the Middle East Respiratory Syndrome, is unlikely to cause a SARS-like epidemic based on a number of key differences between the two diseases, according to the largest clinical analysis of the virus yet.

Published in The Lancet Infectious Disease, the study led by Deputy Minister for Public Health from the Kingdom of Saudi Arabia Ziad Memish included an examination of 47 confirmed MERS cases from Saudi Arabia dating between Sept. 2012 and June 2013. In doing so, the researchers discovered a notable difference between apparent vulnerabtility to infection.

SARS first emerged in China in 2002, ultimately killing nearly 800 people before it was contained officially roughly two years later. And while the two diseases share many symptoms, the team found 96 percent of the MERS cases they analyzed occurred in individuals with underlying chronic medical conditions, such as diabetes, high blood pressure, chronic heart disease and chronic renal disease.

"In contrast to SARS, which was much more infectious especially in healthcare settings and affected the healthier and the younger age group, MERS appears to be more deadly with 60% of patients with co-existing chronic illnesses dying, compared with the 1% toll of SARS," Memish said in a press release.

Though he cautions that the current mortality rate of MERS, which scientists say is roughly 50 percent, is "probably spurious" since physicians and researchers are only aware of the most severe cases -- a point co-author Ali Zumla of University College London further stressed.

"The recent identification of milder or asymptomatic cases of MERS in health care workers, children, and family members of contacts of MERS cases indicates that we are only reporting the tip of the iceberg of severe cases and there is a spectrum of milder clinical disease which requires urgent definition," he said.

In the end, Zumla argues, researchers have much to learn yet about the disease, including its source and predisposing factors for susceptibility to infection.

However, in the meantime, he resassured that "infection control measures within hospitals seem to work."