The unforeseen crisis brought on by the SARS-CoV-2 virus has created a global surge in demand for diagnostic and monitoring tests and a subsequent worldwide shortage in supplies of appropriate testing equipment for COVID-19.
The two organisations that represent the medical technology sector – namely the SA Medical Technology Industry Association (SAMED) and the Southern African Laboratory Diagnostics Association (SALDA) – want to contribute to informed discourse relating to the use of medical technologies, including tests for COVID-19.
In response to the issue of self-administered SARS-CoV-2 test kits, SAMED and SALDA emphasise that safety must be a priority. Following reports that a number of these tests are becoming available in the country, the associations highlight that most of these products would not have been checked or registered by the SAHPRA (South African Health Products Regulatory Authority). Members of the public who might want to use them should be cautioned that the quality and efficacy of these products are unknown. Hence, it is essential that medical responses to COVID-19 – including testing – are implemented by appropriately equipped and trained personnel.
Emphasising this message, Sarah Cohen, SALDA’s executive officer says: “All testing for COVID-19 should be done by healthcare professionals in an accredited laboratory or approved facility, with all the relevant quality control measures in place.”
Avanthi Govender Bester, the chairperson of SAMED says: “Our knowledge about how SARS-CoV-2 is transmitted, how long a person is infectious to others, the building of antibodies and immunity and optimal treatment choices is still limited. All of this relates to how we screen, test, diagnose and monitor the treatment of COVID-19. We have engaged with member companies, health policy makers and healthcare providers to ensure alignment of strategy as it impacts the optimal use of available testing equipment.”
At present, two main types of tests exist for COVID-19: those that detect the presence of a virus; and tests that can detect previous infection and the body’s immune response to the virus.
Cohen says: “Patients suspected of being infected are currently tested with a PCR (polymerase-chain reaction) laboratory-based molecular test. This is the gold standard for testing and must be performed in equipped laboratories by trained staff.”
A PCR test looks for the virus when an individual is suspected of having an infection. Throat or nose swabs are used as samples to test for the virus in a laboratory. If the test shows a positive result, it is an indicator that the patient has the virus and that the individual is likely to be infectious.
However, the test can give a negative result – including a “false negative” – if the test was done during the time (a window period) when the individual’s viral load was too low to be detected.
“The negative results do not rule out infection or that a person can infect others. Based on the current data, patients with COVID-19 are infectious for up to two weeks from the time when they acquire the infection,” says Cohen.
Govender Bester says that in light of international pressures that make the purchase of necessary quantities of tests difficult, SAMED and SALDA urge the health system – and the public – to put the available approved tests to best use. “Foremost, we need to be able to test acute cases – both members of the public and healthcare workers who are most likely to have COVID-19 and exhibit the recognised symptoms.”
SAMED and SALDA await the anticipated release of the National Testing Algorithm by the Health Department, which will also guide the future of the South African testing landscape.
Explaining the second type of test method, Cohen says that it is designed to detect the immune response against the virus. The use of a serological test would allow for the detection of antibodies to SARS-CoV-2 which indicates that a person has had an infection before.
One such test, sometimes referred to as a “rapid test”, entails a finger prick and checking for the presence of antibodies in the person’s blood. This type of test cannot be used for diagnosing an active COVID-19 case. When performed in large portions of a population, these tests could provide valuable information on the diffusion of the infection in the population and could therefore guide authorities on appropriate measures.
In addition, there is a serological laboratory-based test that is done by high-throughput, automatic analysers and qualified, specialist laboratory personnel. This test is performed on blood samples that are collected and sent to laboratories for analysis. In most instances, these tests are of a higher quality and accuracy than the previously mentioned “rapid tests” as results are interpreted by trained medical professionals.
“Testing is an essential tool to stop the spread of the SARS-CoV-2 virus – and other infections we might need to tackle in the future. Developing and manufacturing tests is critical to identifying which patients need treatment and which patients must be isolated. As voices of the South African medical technology industry, SAMED and SALDA are committed to participating in efforts aimed at ensuring that everyone has access to the tools they need to prevent, diagnose and treat the disease,” concludes Govender Bester.
Issued on behalf of SAMED and SALDA by Meropa Communications