Abstract
Diagnostic tests for identification of people infected with severe acute
respiratory syndrome coronaviruses is crucial in the control and
prevention of SARS-CoVs. Towards the ending of the year 2019, a novel
coronavirus that resembles SARS-CoV called COVID-19 that causes
respiratory disease appeared in China and later spread subsequently
through more than 215 countries including Australia, Japan, Italy,
Germany, South Africa, United Kingdom and the Unites States and has
continue to spread worldwide. The genome of SARS-CoV is 29,727
nucleotides in length, and the genome organization is similar to that of
other COVID-19. Generally, viral infection have been diagnosed in the
laboratory through detection of viral antigens, nucleic acid, specific
antibodies and by isolation and electron microscopy. Coronaviruses were
detected usually from respiratory samples and blood by ELISA,
Immunoflourescence test, Immunoblot and polymerase chain reaction. For
epidemiological purposes the virus have to be cultured prior to other
techniques in order to obtain good results. However, cultural technique
is not recommended for COVID-19. The highest yield for the detection of
SARS-CoVs results from real time polymerase chain reaction (RT-PCR).
Sensitivity and specificity of IgG-IgM rapid diagnostic test (RDT) kits
were acceptable as they are speedy, easy to use and cheap procedures
which contribute to its application in mass testing. However, it cannot
be employed instead of RT-PCR to detect COVID-19, but can be optional
and complementary test. Development of rRT-PCR/IgG-IgM combined test kit
could be helpful to ease diagnosis and the disease management, therefore
more efforts are needed to investigate alternative diagnostics for
coronaviruses.