Nature couldn't have found a better time to joke with humanity that is at war with itself. A masked microscopic pathogen has received as much or more media attention than any sworn macro enemy of state since November 2002 till date. That stealthy virus causes the much-feared disease called SARS. Severe Acute Respiratory Syndrome (SARS) is a pneumonia-like acute respiratory disease that is caused by an insidious virus whose identity is yet to be confirmed. It was first reported from the Guangdong province of China and probably cruised across the world in travelers' respiratory tracts. Global cumulative number of cases of the disease is reported to be 1408 including 53 deaths since 16th November 2002 to 27th March 2003 in Asia, North America and Europe. These figures are as per the latest (27th March 2003) updated 'cumulative number of reported cases (SARS)' of WHO. (1)
Moderate to high fever greater than 100.4Â°F (38Â°C) marks the onset of the disease. The patient sometimes additionally gets chills, headache, malaise, and body aches, and mild respiratory symptoms. As the disease progresses, the patient may experience a dry, nonproductive cough after 3 to 7 days. The cough may be accompanied by or lead to anoxia or lack of oxygen in the blood.
Two types of SARS patients have been identified:
1. A more fortunate 90 percent of patients develop characteristic symptoms and after 6 to 7 days of disease progression there is spontaneous resolution of symptoms and these patients feel better. Experts argue that this is probably due to better immunological responses (antibody production) by the patient's body.
2. A less fortunate 10 percent of patients develop severe respiratory and fever symptoms that progresses to acute respiratory distress syndrome. Many of them may need mechanical ventilation. It has also been noted that those who succumb to the disease have other accompanying severe illnesses. (2)
As a policy, national public health authorities report to WHO on the areas in which local chain or chains of transmission are occurring. These areas are defined as 'Affected Areas'. China, the country said to be the origin of SARS has the largest number of cases i.e. 806 of which 34 have died. 792 cases, including 31 deaths, reported from Guangdong Province cover the period 16 November 2002 to 28 February 2003. The cases in China were compiled from investigations as well as hospital reports and may include suspect as well as probable cases of SARS.
Hong Kong Special Administrative Region of China reported 367 cases with 10 deaths. One death attributed to Hong Kong occurred in a case medically transferred from Viet Nam. Taiwan province reported 6 cases with no deaths. The affected areas are Guangdong, Hong Kong, Shanxi and Taiwan.
Other affected areas are Singapore, Toronto (Canada) and Hanoi (Viet Nam). Singapore has the highest number of SARS cases after China, with 78 cases of which 2 have died. Viet Nam reported 38 cases with 2 deaths, while Canada reported 28 cases with 3 deaths. Germany reported 4 SARS cases. Romania, Thailand and UK reported 3 cases each, Italy, Ireland and Switzerland reported 2 each and France reported 1 case.
45 cases have been reported in the U.S. However, the status of local transmission has yet to be determined. Due to differences in the case definitions being used at a national level probable cases are reported by all countries except the U.S.A. The U.S. is reporting suspect cases under investigation. According to WHO, as SARS is a diagnosis of exclusion the status of a reported case may change over time. This means that previously reported cases may be discarded after further investigation and follow-up.
Not A Pandemic
Experts have determined that close contacts of SARS cases, particularly health care workers and family members are more prone to developing similar symptoms. Transmission is usually through direct contact with respiratory secretions and body fluids of patients with SARS. Top German scientist Bernhard Fleisher, head of Hamburg's Bernhard Nocht Institute for Tropical Medicine (BNI) believes that this disease will not become a global epidemic and is not "as contagious and does not spread as easily as first assumed". (3) WHO experts also believe that this disease won't become a pandemic.
On March 25, U.S. Centers for Disease Control and Prevention (CDC) announced that its scientists had detected a previously unrecognized coronavirus in 2 patients with SARS. Microbiologists at the University of Hong Kong reported on 27th March 2003 that they had identified a virus that is close to the coranavirus detected by CDC as the SARS pathogen. Coronaviruses are a family of virus that is the second leading cause of colds in humans. They have been earlier reported to cause upper respiratory infections in premature infants. (4)
Other laboratories in Hong Kong, Germany and Singapore are proposing the causative pathogen to be a new virus from the family of polymyxovirus that are known to cause respiratory illness, measles and mumps. (5) Experts at WHO are confident that coronavirus is the SARS culprit but are wondering if the polymyxovirus is a helper virus or just a co-infection with no role in SARS. Researchers in China and Hong Kong are working on the diagnostics, while some scientists have even suggested antivirals like ribavirin as potential treatment for SARS.
The CDC has activated its Emergency Operations Center (EOC) in the wake of SARS. The EOC is distributing health alert notices to travelers who may have been exposed to cases of SARS and assisting state and local health departments in investigating possible cases of SARS in the United States. EOC is also providing safe specimen-handling guidelines to laboratories and is analyzing laboratory specimens to identify a cause for SARS. EOC has deployed more than a dozen CDC medical officers, epidemiologists, infection control specialists, and pathologists to support the World Health Organization in the global investigation. (4)
SARS has impacted international air and sea travel in a major way, and travel is being more supervised if not officially restricted. Screening of persons traveling from the affected areas to other parts of the world to quarantine those found to be infected is recommended by experts at WHO. Isolation of suspected cases have lead to closure of some schools and other institutions in affected areas. Restrictions for hospital visitors have been tightened. The WHO also recommended new measures to prevent travel related spread of SARS in its latest update on 27th March 2003.
What is evident from the information available on this new mysterious disease is the tremendous amount of co-operation and communication that is on-going between experts at China and Hong Kong with experts in other parts of the world and particularly with WHO and CDC. The exhaustive press briefing by experts at WHO on 23rd March 2003 also proves this point. The world would have one major health crisis archived should expert predictions that SARS is likely to abate in the next few weeks becomes reality.
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Last updated on: 27/08/2010