'THE CLINICAL PICTURE OF SARS'

1.     Definition

SARS is a condition of unknown etiology probably caused by a corona virus, that has been described in patients in Asia, Canada & Europe.

2.     Etiological Agent

A novel corona virus, for which CDC recently completed genome sequencing is believed to be responsible for global Epidemic of SARS. (This virus is different from the known bird and pig corona virus.)

3.    How SARS Spreads?

The primary way that SARS appears to spread is by close person-to- person  contact. Most cases of SARS have involved people who cared for or lived with someone with SARS, or had direct contact with infectious material (for example, respiratory secretions) from a person who has SARS. Potential ways in which SARS can spread include touching the skin of other people or objects that are contaminated with infectious droplets and then touching their own eye(s), nose, or mouth. This can happen when someone who is sick with SARS coughs or sneezes droplets onto themselves, other people, or nearby surfaces. It is also possible that SARS can spread by other ways that are currently not known.

4.      Age of Onset       

Identified in adults aged 25-70 years. Few cases have been reported among children < 15 years.

5.     Clinical Features

Incubation period is typically 2-7 days. The illness begins with prodrome of Fever (>100.4% /38^o  C). Fever is often high, sometimes associated with chills & rigors. There may be other accompanying symptoms like headache, malaise & myalgia. At the onset of illness, some persons have mild respiratory symptoms. Typically, rash neurological or gastrointestinal symptoms are absent; however some patients have reported diarrhea during the febrile prodrome.

After 3-7 days, a lower respiratory phase begins with the onset of dry, nonproductive cough, dyspnoea, which may be accompanied by or progress to hypoxemia. In 10-20% of cases, respiratory illness is severe enough to require intubation and mechanical ventilation.
 

6.    Case Fatality Rate

Defined by WHO is approx 3%.

7.    The latest case definition criteria is as follows

1) Clinical criteria

2) Lab Criteria

3)  Epidemiologic Criteria