Novel Coronavirus 2019 nCoV Antibody Test

Coronaviruses are the largest family of RNA viruses. They evolved over thousands of years with bats as their hosts, however, they can infect other species of animals as well as humans. In humans, coronaviruses can cause a variety of symptoms, ranging from a simple cold to severe acute respiratory syndrome type 2 (SARS).

In November 2019, a new human strain of the virus, SARS-CoV-2, was initially in the Chinese city of Wuhan. Its rapid spread worldwide prompted the World Health Organization (WHO) in March 2020 to declare a COVID-19 pandemic.

The antibody test is a rapid immunochromatographic flow test that detects molecular produced by the immune system in response to SARS-CoV-2 infection and helps identify people who have been infected relatively recently or in the past even if they are asymptomatic. Blood samples are used to carry out the antibody test, where the detection of three antibody types produced by the human body against the virus, IgA, IgG and IgM, takes place. IgM antibodies provide the first line of defence during the viral infection. IgA antibodies indicate a recent infection and are an indicator of a first immune response. IgG antibodies are essential for the development of long-term immunity.

IgG / IgM antibody detection test

This test is used to determine IgG and IgM antibodies qualitatively and quantitatively against SARS-CoV-2 in serum or blood plasma. Since there is a time lag between the viral infection and the production of antibodies, every negative result obtained must be verified via molecular examination.

The principle behind this technology, is based on the T-line coating of the cassette with CoV recombinant virus antigen, which is recognised and bound to anti-SARS-CoV-2 antibodies and the coating of the control line (C-Line), with a second polyclonal IgG antibody. The antigen is tagged with UCP particles that emit a light signal, when a complex between the antigen and the antibody present in the sample is formed. The analyser reads the signals from the T- and C- lines, calculating their ratio, giving a form of quantification of the concentration of SARS-CoV-2 antibodies present in the sample.

In our laboratory, a designated area has been exclusively designed for this examination with all the protection measures required, while the blood samples are collected by specialized personnel with special equipment. The execution of the examination is done by experienced staff specially trained to answer all the questions of the examinees.