Researchers hope to quell the fear that the world might experience another dangerous health pandemic, CBS News reported.

A new study, published Thursday in the journal the Lancet Infectious Diseases, showed Middle Eastern respiratory syndrome (MERS) to have key differences to severe acute respiratory syndrome (SARS).

In almost every case of MERS, 70 infected overseas since September, the patient already had a chronic health condition. This made MERS look stronger than it was because it was killing those who were already sick. SARS infected the healthy and the unhealthy alike.

"Despite sharing some clinical similarities with SARS, there are also some important differences," lead researcher and Deputy Minister for Public Health, Prof Ziad Memish, told BBC News. "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."

The study is the largest to date on MERS and analyzed 47 (46 adults, 1 child) Saudi Arabian patients of the disease from Sept. 1, 2102 to June 15, 2013. According to the World Health Organization (WHO), Saudi Arabia is believed to be the origin of MERS.

Like SARS, MERS is a viral respiratory disease caused by a coronavirus, which is also known to cause the common cold. MERS patients experience fever, cough and shortness of breath. 98 percent of MERS patients were admitted to the hospital with a fever, 83 percent with cough and 72 percent with shortness of breath. 32 percent also had muscle pain and 25 percent had gastrointestinal symptoms like vomiting and diarrhea.

WHO reported 90 cases of MERS as of July 21, 45 of which resulted in death. Patients have been located in Jordan, Qatar, Saudi Arabia and the United Arab Emirates. Other cases were identified in the U.K., France, Germany, Italy and Tunisia, but those patients received the disease directly from the Middle East.

"We want to make sure we can move as quickly as possible if we need to," WHO flu expert Keiji Fukuda said at a news conference in June. "If in the future we do see some kind of explosion or if there is some big outbreak or we think the situation has really changed, we will already have a group of emergency committee experts who are already up to speed so we don't have to go through a steep learning curve."

Memish said the high mortality rate is also likely due to only picking up severe cases.

"We are... missing a significant number of milder or asymptomatic cases, he said. "So far there is little to indicate that MERS will follow a similar path to SARS."