It is a viral respiratory disease in humans which is caused by the SARS coronavirus (SARS-CoV). It is a severe, life threatening form of pneumonia. SARS originated in the Guangdong province of southern China in 2002. The infection quickly spread to other countries (a pandemic), and resulted in more than 8,000 cases and 774 deaths before the virus was eventually brought under control.
SARS has flu-like symptoms that usually begins after incubation period of 2-10 days. They include:
Coronaviruses are positive-strand, enveloped RNA viruses that are important pathogens of mammals and birds. This group of viruses cause enteric or respiratory tract infections in a variety of animals, including humans, livestock, and pets.
Polymerase chain reaction (PCR): It can detect genetic material of the SARS-CoV in various specimens like blood, stool, respiratory secretions or body tissues Sampling for Severe Acute Respiratory Syndrome (SARS) diagnostic tests.
ELISA (Enzyme Linked ImmunoSorbant Assay): A test detecting a mixture of IgM and IgG antibodies in the serum of SARS patients yields positive results reliably at around day 21 after the onset of illness.
IFA (Immunofluorescence Assay): A test detecting IgM antibodies in serum of SARS patients yields positive results after about day 10 of illness. This test format is also used to test for IgG. This is a reliable test requiring the use of fixed SARS virus on an immunofluorescence microscope. Positive antibody test results indicate a previous infection with SARS-CoV. Seroconversion from negative to positive or a four-fold rise in antibody titre from acute to convalescent serum indicates recent infection.
Negative antibody test results: No detection of antibody after 21 days from onset of illness seems to indicate that no infection with SARS-CoV took place.
Treatment is mainly supportive and may include:
To avoid spreading the infection, it is important to follow the prevention advice outlined below: