All over the world, millions have been infected with SARS-CoV-2 and it is a known fact that among those infected several were asymptomatic and did not know it. While molecular tests are considered the gold standard, antibody tests are playing an important role in detecting these asymptomatic cases.
By now, almost all of us know that COVID-19 is a respiratory disease and affects different people in different ways. Some develop a mild to moderate self-limiting illness, with symptoms including fever, a dry cough and lethargy, while some infected individuals, particularly those over 60 years of age and with certain underlying co-morbidities, experience severe symptoms that may be fatal.
Role of epidemiological investigations
The world over, health officials have attempted to contain the spread of COVID-19 through intensive epidemiological investigations coupled with isolation of cases and quarantine of close contacts. However, epidemiological data are negligible, as it has been difficult not only to establish the source of infection but also ascertain the possible extent of spread.
The widely used RT-PCR tests would not be useful if these infected individuals have recovered and no longer shed the virus. These tests require technical expertise to perform and also for sample collection as the concentration of virus varies in different region of respiratory tract. A solution to minimize these risks is using serological based tests. It is now well-established that to identify convalescent cases and aid investigations and containment efforts, serological tests are needed. These tests must be deployed appropriately for use in disease surveillance, prognosis, return-to-work screenings, and more.
Antibody testing for effective surveillance
Antibodies are specialized proteins, also known as immunoglobulins that recognize foreign particles (antigens). IgM and IgG antibodies to SARS-CoV-2 develop between 6–15 days post disease onset. IgM is the first immunoglobulin to be produced in response to an antigen and is primarily detected during the early onset of disease, while IgG is the most abundant immunoglobulin and is maintained in the body for a long-term even after clearance of infection.
Besides indicating some level of immunity, the presence of these antibodies could help identify those who have been infected but never realized they had the disease. Early research shows a large number of people may have had mild or no symptoms at all, and this group might be spreading the virus more than previously thought.
Therefore, serology testing for SARS-CoV-2 is at an increased demand in order to better quantify the number of cases, including those that may be asymptomatic or have recovered. Further, it is serologically established that the person is now immune. Most importantly, it can aid in reducing the stress on the frontline warriors. Another upside of these tests is that they are relatively inexpensive, easy-to-use and with results available in few hours.
How can ELISA tests help in this pandemic situation?
In the context of COVID-19, ELISA tests should be used as co-markers to identify, treat, and isolate infected individuals. At the public health level, ELISA allows for the successful implementation of comprehensive testing and surveillance strategies.
The test might also help with convalescent plasma therapy. In this therapy, doctors collect blood from people who have recovered from the disease, and transfuse it to the infected persons. It is believed that the antibodies in the donor’s blood help in the recovery. The ELISA test could help identify people with IgG antibodies who might be able to donate their blood.
Transasia-Erba Group has developed a reliable and automation-friendly ErbaLisa COVID-19 IgG/IgM ELISA kit, allowing for comprehensive and accurate antibody assessment. Our COVID-19 antibody ELISA kits assure the best performance and simple interpretation of results.