Q&A: What PCPs need to know about at-home tests for COVID-19

Long, daunting lines at COVID-19 test sites have many people turning to at-home tests, according to reporting by The New York Times.

Although these at-home tests may be hard to find, efforts to increase access are underway. Last month, the Biden administration announced that it is preparing to distribute 500 million free at-home COVID-19 testing kits to Americans. On Monday, the administration said it will require insurance companies and group health plans to cover the cost of at-home tests starting Jan. 15.

Healio spoke with Maria Luisa Alcaide, MD, FIDSA, a professor of clinical medicine and director of the infectious diseases research unit at the University of Miami’s Miller School of Medicine, to learn more about the efficacy of at-home tests, how primary care physicians should manage patients who test positive with an at-home test and more.

Healio: How effective are at-home tests?

Alcaide: At-home tests are an accessible and fast way to detect infections with SARS-CoV-2. They detect SARS-CoV-2 antigens, are effective in detecting infections and are typically less sensitive than PCR tests. At-home tests have better results in symptomatic individuals in the first week of symptoms than in those without symptoms. Positive at-home antigen tests are very specific and an effective way to detect infection. They can have false-negative results early or late during the infection, or if they are performed incorrectly.

Healio: Does efficacy vary depending on the variant?

Alcaide: At-home antigen tests are capable of detecting SARS-CoV-2 variants. They have reduced sensitivity to detect omicron.

Healio: Do you recommend any at-home tests over others?

Alcaide: There are several tests that are approved by the FDA for at-home antigen testing. Sensitivity and specificity are similar for these tests.

Healio: There have been reports that people are swabbing their throats because they are not confident in the accuracy of at-home tests. What does current evidence suggest about throat vs. nasal swabbing? What should PCPs be telling patients who ask about throat swabs for at-home tests?

Alcaide: There have been some anecdotal reports of patients who have had a positive at-home test from a throat swab after receiving a negative from a nasal swab. The FDA has not cleared the at-home antigen test for use in the throat; therefore, the recommended use by PCPs should be in the nose.

Healio: The FDA recently approved two oral antivirals. Should PCPs prescribe these to patients who test positive with an at-home test? Or would the patients need further testing before receiving a prescription?

Alcaide: The recently approved oral antivirals nirmatrelvir-ritonavir (Paxlovid, Pfizer) and molnupiravir (Merck) have been approved for outpatient treatment of mild to moderate COVID-19 in individuals with risk factors for progression to severe disease. There is limited availability of these antivirals at the moment. The effectivity of the antivirals is higher early in the course of the disease, and they should be initiated as soon as possible. A positive test in an individual with symptoms is highly indicative of infection; therefore, they can potentially be prescribed to a patient with an at-home rapid test without the need of further testing. Additional testing may delay the initiation of treatment.

Healio: These antivirals are approved for patients at high risk for progression to severe COVID-19. Who does this include?

Alcaide: Patients at high risk for severe progression include those with cancer, transplant recipients and those with an impaired immune system for other reasons, such as advanced age, diabetes, HIV and other chronic comorbidities.

Healio: Is there anything else you would like to add?

Alcaide: Indications for testing with at-home tests and to prescribe the available treatment are changing rapidly based on new available data.

References:

Biden-Harris administration requires insurance companies and group health plans to cover the cost of at-home COVID-19 tests, increasing access to free tests. https://www.cms.gov/newsroom/press-releases/biden-harris-administration-requires-insurance-companies-and-group-health-plans-cover-cost-home. Published Jan. 10, 2022. Accessed Jan. 11, 2022.

Hassan A, Kambhampaty AP. Covid updates: Long waits and extra expense for many to get tests in U.S. https://www.nytimes.com/live/2022/01/08/world/omicron-covid-vaccine-tests. Printed Jan. 8, 2022. Accessed Jan. 10, 2022.