Abstract:
Countries globally are affected by the COVID-19
pandemic, with nearly two million cases and 120 000
deaths occurring within 4 months of the discovery of
the severe acute respiratory syndrome coronavirus-2 in
December 2019 in China. Accurate diagnoses of cases is
key in managing the pandemic by identification, isolation
and treatment of patients and defining the epidemiology
of the virus. By mid-January
2020, a scientist from China
published the full genome of the virus, which facilitated
the development of accurate molecular diagnostic assays.
By the end of January 2020, the WHO, in collaboration
with laboratories in Asia, Europe and the USA, published
several real-time
reverse transcriptase PCR (rtRT-PCR)
protocols that allowed identification of cases and
development of commercial assays. Clinical investigations
facilitated development of accurate case definition and
guidance for laboratories on the optimum specimens and
procedures for diagnoses. Currently, laboratory-based
rtRT-PCR
is the recommended test for diagnoses of acute
cases to ensure patients can be identified and isolated
and to facilitate the public health response. However,
due to delays in diagnoses, severe shortage of tests and
laboratory capacity, point-of-
care
molecular or antigen
tests are becoming more attractive. Although serological tests are not suitable for diagnoses of acute cases,
they are important to define epidemiological questions,
including attack rate in the population, and to identify
immune individuals. This review aimed to summarise the
current available information for diagnoses of cases and
to aid laboratories and healthcare workers to select the
best assays and procedures.
