Think you have Covid-19?
When to get tested for Covid-19…
As a nurse practitioner working in infectious diseases at Johns Hopkins Bayview, I often get asked questions about Covid-19. Most recently the question of, “when do I get tested?” was raised and here are my recommendations supported by some of our leading health institutions.
There is so much confusion regarding when to get tested for Covid-19 and rightly so. This virus emerged in late 2019 with not a lot known about it other than it is highly contagious, spreads by respiratory droplets, does things to the body that we are still trying to understand, and it is deadly. Each day we gather more and more evidence about Covid-19: how we can prevent ourselves from getting the virus, what we should do if we get sick, when should we seek help, who is most vulnerable and why.
So, what should you do if you think you have been exposed to Covid-19? The answer is not straightforward. Let us look at what some of our leading health institutions recommend.
The CDC recommends getting tested for Covid-19 if:
1) You have symptoms of Covid-19.
2) You have had close contact with someone with confirmed COVID-19 (close contact refers to being within 6 feet of an infected person for at least 15 minutes) — this is exposure to Covid-19.
3) You have been asked or referred to get tested by your healthcare provider, local, or state health department.
Massachusetts Institute of Technology (MIT) posted an article answering the question, “When should I be tested?” While the article does not specifically state the exact timing after exposure to Covid-19 that you should be tested, it does bring up valid points that may help guide your decision on when to get tested. For example:
You should not expect a positive Covid-19 test one day after exposure.
The average time from Covid-19 exposure to symptom onset is about 5–6 days, with people showing symptoms 2–14 days after exposure.
How this pertains to when you should get tested…
A person infected with Covid-19 is most contagious 24–48 hours before they experience symptoms. If the average onset of symptoms is 5–6 days, then they are most contagious at 3–4 days after contracting the virus or post-exposure. With this said, you should wait at least 3–4 days after exposure to get tested for Covid-19. However, if you become symptomatic before this 3–4 day mark, then you should get tested and quarantine accordingly.
References
Centers for Disease Control and Prevention. (2020, September 18). Overview of testing for SARS-CoV-2 (COVID-19). Retrieved October 13, 2020, from https://www.cdc.gov/coronavirus/2019-ncov/hcp/testing-overview.html
Centers for Disease Control and Prevention. (2020, August 24). COVID-19 testing overview. Retrieved October 13, 2020, from https://www.cdc.gov/coronavirus/2019-ncov/symptoms-testing/testing.html
Harvard Health Publishing. (2020, October 8). If you’ve been exposed to the coronavirus. Harvard University. Retrieved October 13, 2020, from https://www.health.harvard.edu/diseases-and-conditions/if-youve-been-exposed-to-the-coronavirus
Redford, G. (2020, October 5). Your COVID-19 testing questions — answered. Association of American Medical Colleges. Retrieved October 13, 2020, from https://www.aamc.org/news-insights/your-covid-19-testing-questions-answered
Schive, K. (2020, July 17). When should I be tested? MIT Medical. Retrieved October 13, 2020, from https://medical.mit.edu/covid-19-updates/2020/07/when-should-i-be-tested
