RAPID ANTIGEN TESTS
How should I feel about a rapid antigen test?
Rapid antigen tests have been marketed for a full year. Their levels of sensitivity and accuracy have reached a very competent level, although they are not yet comparable to the gold standard of testing, the PCR test. It is important to know that a rapid antigen test only detects the virus if the amount of the virus in your body is very high: usually four or five days after developing symptoms. Individuals may, however, be infectious before they have developed any symptoms, as well as several weeks after they have developed symptoms, and the antigen test is not capable of detecting this.
Can I use the rapid antigen test to test myself at home?
Rapid COVID-19 antigen tests have now reached the Estonian market. These tests have been designed by the manufacturer for home use. More than ten compliant rapid antigen tests for self-testing at home have reached the European Union market, and more are about to arrive. Therefore we advise non-professional users (anyone who is not a medical professional) to prefer those tests which are market as ‘for self testing’ and which have the notified body’s four-figure identification code next to the CE label. These tests have passed proper compliance assessments, while also being subject to manufacturer liability and coming equipped with user instructions which are designed for non-professional users. The information on the packaging and the user instructions must be fully translated into Estonian.
At the start of this summer only rapid antigen tests for professional use were available on the Estonian market. Labelling them ‘for professional use’ means that these tests are meant only for use by healthcare professionals or under the control of healthcare professionals. Their use for self-testing by non-professionals is not prohibited, but the fact should be kept in mind that, in such cases, the tests are not being used for their intended purpose. Potential mistakes which could be made when taking or interpreting the test reduce the reliability of the test, and non-professional users are likelier to get false positive or false negative results.
How can a SARS-CoV-2 rapid antigen test be taken?
In some cases, attempts have been made to sell tests which have been designed only for professional use, describing them as tests which are suitable for self-testing. The Health Board would like to caution buyers to be careful about purchases in order to avoid mistakenly buying a rapid test for medical professionals for home use. Should this occur, the consumer may return the test to the seller.
Which rapid antigen tests should I use?
Non-professional users should prefer the domestic antigen tests (for self testing) which are available on the Estonian market.
Healthcare providers are advised to use verified rapid antigen tests which have been tested in European Union member states. The Health Security Committee regularly issues an updated list of tests which meet the minimum requirements, where such tests are in use in member states and where the results of such tests are mutually acknowledged across member states. These lists can be found on the following website: https://ec.europa.eu/health/sites/default/files/preparedness_response/docs/covid-19_rat_common-list_en.pdf (PDF)
What should I do if I decide to use a rapid antigen test?
Before taking the test, carefully read the packaging leaflet. Firstly ensure that you have collected the sample properly, exactly as described in the user instructions. The collection of a nonlaryngeal sample is an uncomfortable procedure which very often causes tear flow. It is more comfortable to collect the sample from the sidewalls of the nose, but proper contact with the mucosa on the sidewalls is very important in this case. If you fail to collect the sample properly, you will not receive a reliable test result.
Collect the sample in a room which is not used for having means, which is properly ventilated, and where surfaces can be cleaned and disinfected. Make sure that no individuals who are not involved in the process are present in the room, as the collection of the sample is a potentially infectious process. Before using the test, clean your hands and any surfaces which you are going to use. Make sure that you also clean those surfaces after completing the test, as well as your hands.
What if I test positive?
A positive test result means that it is very likely that you are infectious, and you should immediately stay home and call your family physician or the family physician advisory line (1220 or +372 634 6630 also for calls from abroad). Unless decided otherwise by the physician, the rapid antigen test result should be confirmed by a PCR test for your positive test result to be registered in the Health Information System. In this case, you will be officially entitled to a certificate for sick leave, and you will also be exempted in the future from the obligation to self-isolate, as you will already have had the disease. You must also let your close contacts know that they are required to self-isolate at home.
What if I test negative?
If you are sure that the sample was collected properly, you have no symptoms which are characteristic of COVID-19, and you are not aware of having come into close contact with individuals who have been infected with COVID-19, you may carry on with your normal life. You should still take all precautions to prevent getting infected, including wearing a face mask, taking care of hand hygiene, and observing social distancing rules. Avoiding private parties, various gatherings, and crowded places is also important.
If you have been in contact with an individual who has been infected with COVID-19 or in the event that you yourself develop any of the symptoms of COVID-19 (such as a headache, tiredness, fever, or cough), your test results may produce a false negative, and you are strongly urged to contact your family physician or to call the family physician advisory line (1220 or +372 634 6630 also for calls from abroad) to book a PCR test.
If you suspect that you may have been infected, it could be the case that the amount of the virus in your body is not yet sufficient for the antigen test to detect it. You should monitor your health condition and repeat the test in a few days’ time if necessary.
When is it reasonable to use a rapid antigen test?
Before visiting any at-risk individuals (before visiting a doctor, or before visiting a care home). It must be kept in mind that a negative test result does not exempt you from the obligation to observe self-distancing requirements and to use personal protective equipment. In some cases, it would be reasonable to be tested before going to work. The tests may also be used for the early detection of infection cases in work collectives. It would also be a good idea to test close contacts in order to check whether or not they have been infected (before they visit a grocery shop or pharmacy).
A negative rapid antigen test result never gives you the right to prematurely end your self-isolation period if you have been infected or are a close contact. An individual still remains infectious even when the infection can no longer be detected by using a rapid antigen test. Rapid antigen tests provide the best results if the tests are regularly repeated at an interval of a few days under the same conditions. Repeated negative rapid test results which are achieved under identical conditions, and a lack of symptoms or close contact with infected individuals, along with responsible social distancing and the use of personal protective equipment all serve to help to prevent the risk of getting infected, as well as reducing the risk of infecting others.