Basics of SARS Virus

SARS corona virus, sometimes shortened to SARS-CoV, is the virus that causes severe acute respiratory syndrome (SARS). It is a positive and single stranded RNA virus belonging to a family of enveloped corona viruses. Its genome is one of the largest among RNA viruses. Corona Virus was first identified in the 1960s, and was named after the crown-like projections on the surface of the virus. They cause respiratory infections in both humans and animals.

Structure:

SARS coronavirus is a single stranded RNA virus belonging to a family of enveloped corona viruses. The virus has 13 known genes and 14 known proteins. These viruses have large spherical particles with bulbous surface projections that form a corona around particles. The envelop of the virus contains lipid and appears to consist of a distinct pair of electron dense shells. The internal component of the shell is a single-stranded helical ribonucleoprotein. There are also long surface projections that protrude from the lipid envelop. The size of these particles are about 80–90 nm.

Major SARS Outbreaks

SARS caused a global outbreak in 2002, spreading from Hong Kong to more than 30 different countries around the world and killing around 800 people.

Although it has not been eradicated its spread was fully contained in 2003. In 2003, a Chinese-American businessman died in Vietnam from a severe flu-like illness. Soon after, reports of a new disease, then termed “atypical pneumonia,” made headlines around the world. As the number of reported cases increased, the World Health Organization (WHO) issued a global warning regarding the disease, now called Severe Acute Respiratory Syndrome (SARS).

While research was going on in developing medicine against the virus, in a recent outbreak in 2012 September, Health experts reportedly identified a new Sars-like virus in a London hospital. This new virus is different from any coronaviruses that have previously been identified in humans. There was also reported small number of other cases of serious respiratory illness in the Middle East.

WHO guidelines

The WHO Guidelines for the Global Surveillance of SARS 2004 makes the below major recommendations and measures to fight against SARS –

• All countries undertake an analysis of their risk of SARS emergence or introduction and develop a contingency plan for the detection and management of SARS should it recur in epidemic form.
• It recommends Bio safety Level 3 as the minimum containment level to work with live SARS-CoV.
• The diagnosis should be expedited with assistance of WHO in investigation of SARS alerts as appropriate, including facilitating access to laboratory services.
• WHO also urges countries to maintain a thorough inventory of laboratories working with and/or storing live SARS coronavirus and to ensure that necessary bio safety standards are in place.
• National public health authorities should report every laboratory-confirmed case of SARS to WHO.
• Patient(s) should be immediately isolated
• Inpatient contacts should be isolated or cohorted away from unexposed patients and transmission-based precautions instituted. They should be placed on active fever surveillance.
• Contacts of persons under investigation for SARS should be traced and placed on twice daily fever monitoring until SARS has been ruled out as the cause of the illness.