SARS

SARS
Synonyms	Severe acute respiratory syndrome
Field	Infectious disease, Pulmonology
Symptoms	Fever, cough, shortness of breath, pneumonia
Complications	Acute respiratory distress syndrome, Respiratory failure
Onset	2–10 days post exposure
Causes	Severe acute respiratory syndrome coronavirus (SARS-CoV)
Risks	Close contact with infected individual, healthcare work
Diagnosis	PCR, antibody tests, chest X-ray
Differential	Influenza, Common cold, Pneumonia from other causes
Prevention	Quarantine, Hand washing, Infection control
Treatment	Supportive care, Mechanical ventilation, Antivirals
Medication	Ribavirin, Corticosteroids (used but efficacy uncertain)
Prognosis	Case fatality rate ~9.6%
Frequency	8,098 cases (2002–2004 outbreak)
Deaths	774 confirmed

SARS. Severe acute respiratory syndrome is a viral respiratory disease caused by a coronavirus known as SARS-CoV. The illness emerged in late 2002 and sparked a major multinational outbreak that was contained by mid-2004. It is characterized by severe pneumonia and a significant mortality rate, particularly among the elderly and those with underlying health conditions.

Overview

Severe acute respiratory syndrome is caused by a novel coronavirus identified as SARS-CoV, a member of the genus Betacoronavirus. The disease gained global notoriety following its initial detection in Foshan, Guangdong province, China. The international response was coordinated by the World Health Organization, which issued a global alert and facilitated collaborative research. The outbreak demonstrated the potential for a novel zoonotic pathogen to cause severe societal and economic disruption, leading to lasting changes in global public health infrastructure and outbreak response protocols.

Causes and transmission

The causative agent is the Severe acute respiratory syndrome coronavirus, an RNA virus whose natural reservoir is believed to be horseshoe bats. The virus is thought to have passed through an intermediate host, such as the civet cat, in wet markets before spilling over into humans. Primary transmission occurs via respiratory droplets produced when an infected person coughs or sneezes. Transmission typically requires close personal contact, and superspreading events were a notable feature of the outbreak, particularly in healthcare settings like the Prince of Wales Hospital in Hong Kong.

Symptoms and diagnosis

Initial symptoms are often flu-like and include high fever, muscle pain, headache, and general discomfort. This typically progresses to a dry cough and shortness of breath, which may develop into low blood oxygen and Pneumonia. Diagnosis involves a combination of clinical evaluation and laboratory testing. Confirmation is achieved through RT-PCR tests on respiratory or stool samples, or through ELISA and IFA serological tests that detect antibodies. Imaging via chest X-ray or computed tomography often shows characteristic patterns of pulmonary infiltrates.

Treatment and prevention

No specific antiviral treatment has proven universally effective. Management primarily involves supportive care, including supplemental oxygen and ventilatory support for respiratory failure. During the outbreak, various agents like Ribavirin and corticosteroids were used empirically, though their efficacy remains debated. Prevention centered on classic infection control measures: rapid identification and isolation of cases, quarantining contacts, strict hand hygiene, and the use of personal protective equipment such as N95 masks. Travel advisories and airport screening were also implemented internationally.

Epidemiology and history

The outbreak is believed to have originated in Guangdong in November 2002, though initial reporting was limited. The disease spread internationally in February 2003 when an infected doctor from Guangdong stayed at the Metropole Hotel in Hong Kong, seeding outbreaks in Vietnam, Singapore, and Canada. Major affected areas included Beijing, Taipei, and Toronto. The World Health Organization declared a global alert in March 2003 and issued travel advisories. Collaborative efforts led by the World Health Organization and agencies like the Centers for Disease Control and Prevention and the Public Health Agency of Canada eventually contained the outbreak by July 2003, with a final tally of 8,098 probable cases and 774 deaths across 29 countries.

Society and culture

The SARS outbreak had profound societal impacts, causing widespread fear, economic losses in affected regions like Toronto and Hong Kong, and significant disruptions to travel and commerce. It exposed weaknesses in international disease surveillance and reporting systems, leading to revisions of the International Health Regulations. The crisis spurred major investments in public health preparedness and influenced the development of protocols later used during the H1N1 pandemic and the COVID-19 pandemic. The outbreak has been the subject of numerous books, documentaries, and studies on crisis management and epidemiological response.

Category:Viral diseases Category:Zoonoses Category:Epidemics