COVID-19 Rapid Test At Home
Testing is one of the most critical strategies in the management of the COVID-19 pandemic. It enables timely diagnosis, quick access to healthcare, and immediate isolation to help curb the spread of SARS-CoV-2. You should be tested if you experience symptoms and/or had an exposure to a person who might be infected with the virus regardless of your vaccination status.
With the introduction of at-home rapid antigen test kits, testing have become more accessible and convenient than ever. These kits are relatively more convenient than laboratory-based tests and point-of-care tests as they offer a simple procedure and quick results at the comfort of your own home. They are completely portable, easy to store and available for use whenever and wherever needed. Rapid antigen tests can be purchased online or from pharmacies without prescription regardless of your vaccination and symptom status. Below you can find information on at-home COVID-19 rapid antigen tests, when to use them, and how to use them.
How do at-home COVID-19 rapid antigen tests work?
These tests detect an active COVID-19 infection by identifying SARS-CoV-2- specific protein fragments in a nasal or throat samples. As self-testing kits that detect SARS-CoV-2 antibodies are not currently available, these kits cannot inform the person on a former infection. The overall accuracy of an at-home rapid antigen test is shaped by several factors such as the sensitivity, the specificity, and the sample integrity of the test, the user’s timing, viral load, symptoms and application of the instructions.
How do at-home COVID-19 rapid antigen tests compare to PCR tests?
Despite the convenience of at-home rapid antigen tests, lab-based molecular testing is widely accepted as the golden standard to confirm or dismiss a potential infection with the SARS-CoV-2 virus. Polymerase chain reaction (PCR) tests are one of the most used molecular lab tests. They use selective primers that match a section of SARS-CoV-2 genetic material to amplify a DNA sequence which enables the identification of a present COVID-19 infection. PCR constitutes the most accurate and sensitive method of monitoring SARS-CoV-2. Still, PCR and similar molecular tests take some time to deliver results which can postpone diagnosis, isolation, and access to care. Moreover, the requirement of laboratory equipment and professional personnel contributes to higher costs, overcrowding of healthcare institutions, and higher risks of exposure to SARS-CoV-2 of the healthcare personnel.
Although rapid antigen tests are relatively less sensitive and requires a high viral load to deliver accurate results, research shows that they can successfully detect whether there is a level of the virus that somebody could infect somebody else with. Moreover, unlike molecular lab tests they do not require the use of laboratory equipment, allows for self-testing, and delivers results within 15-30 minutes. While they do not replace PCR testing as the golden standard in any way, rapid antigen tests made it easier for people to monitor themselves by allowing people to easily test for a current infection wherever they are and whenever they need.
When is the best time to test?
Timing of the sample collection linked to exposure to the virus and symptom onset is one of the most influential factors that shape the overall accuracy of the test. This is especially true for rapid antigen tests. The accuracy of the results depends highly on when you take the test and whether you have a high enough viral load for detection at the time of testing. Research demonstrated that if you take a test immediately after exposure to SARS-CoV-2, you might get a false negative result due to very low viral load concentration. Therefore, experts recommend taking a test 2-3 days after suspected or known exposure to the virus. Conversely, if you wait too long to take a test after a suspected or known exposure to SARS-CoV-2, you might miss the highest level of viral concentration. In this case, you might get a faint line indicating a positive result given that you still have an active infection. On the other hand, as the infection status can quickly change, it is recommended to test immediately before a planned event, activity or gathering especially if it includes people who are vulnerable against SARS-CoV-2.
How to use an at-home COVID-19 rapid antigen test
Rapid antigen tests are suitable for self-testing. Each test has a simple set of instructions to be followed by the user. Typically, the user is required to collect nasal or saliva specimen with a non-invasive nasal or oral swab. Then, the user places the swab into a solution, puts some of the solution to the designated area on the test kit, and waits for the result.
Additional points to consider in order to ensure the maximum accuracy include:
– The user should read the results only within the amount of time specified in the instructions. Any interpretation before or after that period may be inaccurate.
– To prevent contamination, the user should make sure to perform the test on a clean surface with clean hands.
– All the components of the kit should be stored under conditions specified in the instructions.
– The expiration date of the kit should be checked before use.
– The tests are designed for single-use. The device should not be reused.
Below you can watch the video about how to use RapidForTM SARS-CoV-2 Rapid Antigen Test Kit (Self-test).
Serial testing
Serial self-testing is when a person tests themselves multiple times or on a routine basis to confirm or rule out a SARS-CoV-2 infection. Performing serial self-testing is known to enhance sensitivity, specificity, and overall accuracy. Indeed, experts argue that testing negative twice when you are infected by SARS-CoV-2 is much less probable than testing negative once. In other words, the biggest shortcoming of at-home rapid antigen tests can be reduced through routine testing.
If you have a negative result but are concerned about being infected due to your symptoms and/or probable or confirmed exposure to the virus, experts recommend quarantining yourself and performing serial testing. Performing routine testing until day six should give reliable information on your infection status. Likewise, performing routine testing with the last test taken as close to the planned event as possible ensures the detection of a potential SARS-CoV-2 infection and prevents you from unknowingly transmitting it. Serial testing is also essential for the self- testing of people who frequently work or live within environments with a high risk of SARS-CoV-2 exposure. Finally, it is useful for people who are in contact with people who are particularly vulnerable against the virus. Some rapid antigen test kits instruct this type of serial testing. In this case, multiple devices may be present in the package and the number of days in-between tests may be specified in the instructions.
