The words “COVID-19 pandemic” and “SARS-CoV-2 virus” have become household names over the past 6 months. Despite its recent discovery, the virus has had a tremendous impact on our lives. As of today, no vaccine or effective treatment has been discovered. While the “Great Lockdown” transitions away from many western nations, the battle against the pandemic has not yet rested. Thus far, two sets of measures have been decisive in combatting the virus. The first set of enforced policies impose a burden on the citizens to follow basic hygiene practices henceforth limiting the further spread of the virus. The execution of the second set of measures concerns the governmental bodies, where they are required to effectively detect, diagnose and track every infected citizen. The latter set of policies call for more practical methods of detection, given the constrained resources of the medical systems.
At the time writing, different types of tests have been executed. The first kind of test which accounts for a vast majority of examinations is called polymerise chain reaction (PCR) testing. The method searches for the viral RNA and is only capable of diagnosis when the patient has been actively infected. The test is performed using a nasopharyngeal swab. The aforementioned procedure, which is a very labour intensive one, results in human errors and incorrect diagnosis. False negatives can be as high as 30%.
The second category of tests is called serologic testing. This kind of test does not specifically search for the virus RNA but the antibodies to COVID-19. The test is carried by using a blood sample. Antibodies are produced by the body when an infection with a specific virus takes place. The antibodies are generally produced one or two weeks after infection and are useful to assess who has been in contact with the virus. This kind of test is less suitable to detect the infection early and are particularly interesting for the epidemiologists who want to build a clearer picture of the general sanitary conditions. The result produced from this test only displays who has been infected, but it does not determine if and for how long immunity has been acquired for this virus.
Other tests are under development, notably, lateral flow assays which look for a biological marker in different samples (urine, blood, saliva,etc.). It works just like a pregnancy test and can be used for in-home testing. Other pharmaceuticals are developing rapid in-clinic antigen testing. In this procedure, the analyzing device uses cartridges where the biological components in each cartridge are used to prove if the patient has SARS-CoV-2 or any of 9 other respiratory diseases.
Depending on the test type and where it is performed, the prices can be high. Furthermore, reagents (2020) are also key components of most tests and are currently in short supply. China and the US are producers and exporters of reagents but both countries have been hit by the pandemic.
In short, tests are in great demand.
Up to now, only a fraction of the population has been tested, and even if testing every person may be useless, having have the capabilities to do so is critical.