Coronavirus Confirmed as Cause of SARS

April 16, 2003 -- After weeks of speculation, a new form of a coronavirus never before seen in humans has been confirmed as the cause of SARS (severe acute respiratory syndrome). The World Health Organization (WHO) made the formal announcement today after scientists completed experiments that replicated SARS in monkeys infected with the coronavirus.

"The pace of SARS research has been astounding," says David Heymann, MD, executive director of WHO's communicable diseases programs, in a news release. "Because of an extraordinary collaboration among laboratories from countries around the world, we now know with certainty what causes SARS."

Conclusive identification of the cause of SARS is a critical step that will now allow researchers to turn their resources toward developing a vaccine or other treatments as well as refine diagnostic tests already in use.

"Now we can move away from methods like isolation and quarantines and move aggressively towards modern intervention strategies including specific treatments and eventually vaccination," says Heymann.

Researchers at the CDC first announced they had identified a coronavirus as the potential cause of SARS on March 24. Soon afterwards, several international laboratories confirmed those findings.

Two known strains of coronaviruses are known to cause the common cold and respiratory infections in humans, and other strains cause more serious illnesses in animals. But the virus identified as the cause of SARS appears to be a previously unknown member of the coronavirus family.

Although researchers had widely accepted this new coronavirus as the primary cause of SARS in recent weeks, a series of conditions known as Koch's postulates had to be met before it could be officially recognized as the cause. Those conditions include: finding the virus in all cases of the disease, isolating the virus and culturing it in the lab from an infected tissue sample, reproducing the disease in a previously healthy host, and identifying the virus in the infected host.

Researchers at Erasmus Medical Center in Rotterdam, Netherlands recently completed the latter two requirements by infecting monkeys with the coronavirus who later developed SARS. Laboratory tests then confirmed the presence of the coronavirus in the affected lung tissue.

The WHO credits unprecedented international cooperation among the 13-member laboratory network established after the SARS epidemic began for finding the coronavirus, now known as the "SARS virus," in record time. The network includes laboratories from China, Canada, France, Germany, Hong Kong, Japan, Netherlands, Singapore, the United Kingdom, and the U.S.

Since the SARS outbreak began in the Guangdong province of China in November 2002, 3,293 cases of SARS have been reported worldwide, including 159 deaths.