EVEN WHILE the world is distracted by air raid sirens and the "shock and awe" launched on the Middle Eastern country, Iraq, international scientists have been locked away in their laboratories, trying to identify the germ that could be causing an emerging infectious disease, described as an atypical pneumonia named Severe Acute Respiratory Syndrome (SARS).
At the beginning of this week, 456 cases of this mystery illness were reported, mushrooming from the 350 cases identified at the end of last week. The death toll reported by the World Health Organisation (WHO) had also quickly moved from 10 at the end of last week to 17 at the beginning of this week.
The scientists suspect that the culprit germ is Paramyxoviridae virus, a family of viruses which includes those causing the mumps, measles and common respiratory illnesses.
The World Health Organisation (WHO) also indicates that this family of viruses includes a sub-family capable of infecting several animal species and was implicated in the 1990s
emergence of severe diseases in people, caused by Hendra and Nipah viruses. The virus jumped directly from animal hosts (horses and pigs) to humans.
Dr. Klaus Stohr, scientist with the WHO's Communicable Disease Surveillance & Response (CSR), said on the weekend, at a press conference in Palais des Nations, that since last Thursday, two more laboratories have identified the Paramyxoviridae virus in specimens from patients with SARS.
He said that the WHO collaborating multi-centre project was turning around data within one week which are normally distributed and digested in months or years.
"More and more laboratories are finding Paramyxoviridae virus. What is promising is that many Paramyxoviridae viruses can be excluded. Hendra and Nipah viruses have not been found nor have mumps and measles. Respiratory syncytial virus was found in few samples.," Dr. Stohr said.
Once the causative germ is detected, Dr. David Heymann, WHO's executive director, Communicable Diseases, says that the next steps include creating a diagnostic test, which may detect infection in the blood or other body secretions.
"Once this had been done, we must use what we call "Koch's postulate" to tell us if we have an organism, and we must be clear that this organism is causing the disease. Then epidemiological studies are needed to determine whether the disease is asymptomatic in some people who have become sick or whether they are healthy and can be removed from the list. There is a whole process of epidemiological investigations after the virus is identified," he said.
The epidemiologists, doing real detective work, trace the illness back to a mysterious illness that sprung up in China last November and believe that they have identified the index (first) case in Hong Kong.
The U.S. Centres for Disease Control (CDC), in tracing the disease's history, said that on February 11, the Chinese Ministry of Health had notified the WHO that between November 16, 2002 and February 9, 305 cases of acute respiratory syndrome of unknown aetiology had occurred in six municipalities in Guangdong province in southern China.
A 47 year-old man who had travelled in mainland China and Hong Kong fell ill on February 26, and was hospitalised shortly after arriving in Hanoi, Vietnam. Healthcare personnel at that hospital fell ill; the patient died on March 13, after he was transferred to an isolation area in Hong Kong.
