Summary of Recent Updates (September 7, 2022):
- Included discussion of updated FDA guidance regarding the need to repeat antigen testing to minimize false-negative results.
- Updated discussion throughout given August 2022 changes to CDC guidance regarding quarantine, elimination of test-to-stay, elimination of routine screening testing, and oter factors. Removed color-coded categories and wording in light of elimination of quarantine after exposures.
- Added information about testing in the setting of new symptoms after nirmatrelvir/ritonavir (Paxlovid) therapy (“rebound”).
- Minor wording changes, including mention of BA.4, BA.5 variants.
Testing for infection with SARS-CoV-2, the virus that causes COVID-19, can inform individual patient care and decision making for parents and families. In addition, population-level testing helps determine what interventions may need to be put in place to control the spread of disease within a community. This guidance is intended to assist pediatricians in understanding indications for SARS-CoV-2 testing as well as test selection and interpretation. The document also provides algorithms for common testing scenarios and information about practical considerations for in-office testing for SARS-CoV-2. No guidance can cover all clinical scenarios, and information regarding SARS-CoV-2/COVID-19 is evolving rapidly. In addition, the spectrum of clinical disease and epidemiology of transmission may differ between SARS-CoV-2 variants in circulation in specific geographic regions. Links to guidelines and research from the Centers for Disease Control and Prevention (CDC) and other organizations are provided for additional information to help guide decision making.
When should patients be tested for COVID-19?
The 3 common reasons and optimal timing for COVD-19 testing are as follows:
- Patients who have symptoms consistent with COVID-19 should be tested immediately.
- Patients who are asymptomatic but have had close contact with an individual who has confirmed or probable COVID-19 should be tested at least 5 days after last exposure; however, these patients should be tested immediately if they develop symptoms consistent with COVID-19.
- Patients who are required to obtain screening tests based on local public health authorities, school districts, or other local organizations should be tested as required.
See AAP Newborn Guidance for additional information about testing newborn infants.
Does the community prevalence of COVID-19 or other respiratory infections influence testing decisions?
Testing for SARS-CoV-2 infection should be guided by clinician judgment in accordance with the prevalence of COVID-19 in a given community. Decisions regarding testing for other pathogens should be informed by local epidemiology, including current levels of community transmission. Diagnosis of some other infections that share symptoms with SARS-CoV-2 (eg, influenza) may be clinically actionable, and coinfections may occur. Children with influenza documented by testing may be treated with an influenza antiviral, with more rapid resolution of symptoms possible, allowing for earlier return to school, per AAP policy. Clinicians should consider local seasonal influenza activity when deciding whether to test patients for influenza. Tests for many common causes of upper and lower respiratory tract symptoms, such as rhinovirus, are not routinely available.
Should vaccination status impact decisions about COVID-19 testing?
Vaccination status of the patient should not guide decisions about testing in the setting of compatible symptoms. This is particularly true for variant strains of SARS-CoV-2 such as Omicron, BA.2, BA.4, BA.5 and subsequent variants, for which vaccines are protective against severe illness, hospitalization and death but less protective against infection and mild illness.
Does recent SARS-CoV-2 infection impact decisions about COVID-19 testing?
Children who have had laboratory-confirmed SARS-CoV-2 infections in the prior 90 days may continue to have positive nucleic acid amplification test (NAAT) results even in the absence of current infection. Because small amounts of viral genetic material may remain detectible for several months after infection, results of NAATs (see Test Selection and Interpretation), including polymerase chain reaction (PCR) tests, may remain positive despite clinical recovery and lack of contagiousness. Antigen test results remain positive for shorter lengths of time. Decisions about testing exposed children with prior confirmed infections in the past 90 days should take into account the possibility of positive NAAT results that do not represent active infection. However, emerging data suggest that reinfections within the 3-month window are more frequent with recent SARS-CoV-2 variants (including Omicron and related strains) and may occur at higher rates in young, unvaccinated individuals. In a child with known exposure or compatible symptoms, there are situations in which it is reasonable to retest within the 90-day window. If testing is performed within that window, antigen testing is generally preferable to NAATs because of the potential for positive NAAT results attributable to prior infection.
On the basis of current CDC guidance:
- If a child has had exposure to someone with COVID-19 and is asymptomatic, but has had COVID-19 within the past 30 days, testing to identify a new infection is generally not recommended.
- If a child has become newly symptomatic after having had COVID-19 within the past 30 days, antigen tests should be used to identify a new infection. If the result is negative, the antigen test should be repeated 48 hours later, per FDA guidance. This recommendation also applies to high-risk children who have received therapy with nirmatrelvir/ritonavir (Paxlovid) and experience new symptoms (“rebound”) after stopping the medication. Per CDC guidance, individuals with rebound symptoms and/or a newly positive test must restart isolation. There is no recommendation for routine testing after nirmatrelvir/ritonavir therapy in the absence of new symptoms.
- If a child has had exposure to someone with COVID-19 but has had COVID-19 within the past 30-90 days (ie, more than 30 and up to 90 days), consider using antigen tests (rather than a NAAT or PCR test) to identify a new infection. The test should be performed at least 5 days after the exposure. Whether the child is symptomatic or asymptomatic, if the antigen test result is negative, the test should be repeated as recommended by FDA guidance. For symptomatic people, the test should be repeated at 48 hours, for a total of two tests. For asymptomatic people, the test should be repeated at 48 hours and, if negative, again 48 hours after the second test, for a total of three tests.
What are the symptoms of COVID-19? Are symptoms different with recent SARS-CoV-2 variants?
Common symptoms of COVID-19 include: fever or chills, cough, congestion or runny nose, loss of taste or smell, shortness of breath or difficulty breathing, body aches, fatigue, headache, sore throat and gastrointestinal symptoms (nausea, vomiting or diarrhea). The decision to test does not differ by the age of the child, although some symptoms such as body aches, shortness of breath and loss of taste/smell are more prevalent in young adults than in school-aged children or infants, and symptoms from nonverbal infants may be more difficult to assess than in older children. Different variants of SARS-CoV-2 may produce a different constellation of symptoms, including asymptomatic infection. In adults, recently prevalent strains, including Omicron, BA.2, BA.4, BA.5 and others, generally appear to cause milder disease compared with earlier SARS-CoV-2 variants. However, there was a marked increase in pediatric hospitalizations in the United States attributable to infection with the Omicron variant. Unvaccinated children were at substantially higher risk for hospitalization than those who had been vaccinated against SARS-CoV-2. Recent variants also appear to be associated with laryngotracheobronchitis (croup) to a greater extent than earlier SARS-CoV-2 variants.
What constitutes close contact for children and adolescents?
- Close contact refers to a distance of less than 6 feet for a cumulative total of at least 15 minutes over a 24-hour period from a person with laboratory-confirmed or probable SARS-CoV-2 infection.
- Close contact in K-12 schools – see CDC guidance for details.
Do asymptomatic close contacts require testing?
Asymptomatic patients who meet the definition of close contact should be tested for SARS-CoV-2 infection at least 5 full days after the most recent contact with the confirmed/probable case. Exposures occurring within 90 days of a confirmed SARS-CoV-2 infection are discussed above.
In what other situations might testing be recommended?
Specific situations in which screening testing may be used include:
- School Attendance and Extracurricular Activities: The CDC and AAP strongly support efforts to provide safe, in-person instruction in K-12 schools and Early Care and Education (ECE) programs. The CDC no longer recommends routine screening testing in K-12 schools or ECE programs. However, at times of high community level transmission of COVID-19, K-12 schools and ECE programs can consider implementing screening testing for students and staff for high-risk activities (for example, close-contact sports, band, choir, theater); at key times in the year, for example before/after large events (such as prom, tournaments, group travel); and when returning from breaks (such as holidays, spring break, at the beginning of the school year). In addition, screening testing may be recommended in certain high-risk congregate settings.
- Workplace Screening:
- Adolescents who are employed may be subject to screening testing as a condition of employment. Such policies are instituted by employers, subject to local public health guidance and applicable laws.
- Travel (detailed information is available at the CDC website related to domestic travel and international travel).
- Health Care Settings: Many hospitals recommend that children receive testing for active SARS-CoV-2 infection prior to outpatient procedures such as elective surgery and for all children admitted to a hospital for any reason. These decisions should be made on the basis of local recommendations and institutional policies. Parents or other caregivers of children may be subject to public health requirements and hospital-based or other health care-based screening policies as well.
Test Selection and Interpretation
Which test should I use for my patients?
For patients who have symptoms consistent with COVID-19 and have not had a confirmed diagnosis of COVID-19 in the past 90 days, either NAATs, which include PCR tests, or antigen tests can be used. A positive result on either test indicates SARS-CoV-2 infection. If the patient has a negative antigen test result, the test should be repeated at 48 hours, for a total of two tests, per FDA guidance regarding repeat antigen testing to decrease the risk of false-negative results. See Test Selection and Interpretation for additional information.
For patients who are asymptomatic but have close contact with an individual with suspected or confirmed COVID-19 and have not had a confirmed diagnosis of COVID-19 in the past 90 days, either a NAAT or antigen test may be used. If the patient has a negative antigen test result, the test should be repeated at 48 hours and, if negative, again at 48 hours after the second test, for a total of three tests, per FDA guidance regarding repeat antigen testing to decrease the risk of false-negative results. See Test Selection and Interpretation for additional information.
Should I provide COVID-19 tests in my office? What should I consider when making this decision?
See Practical Considerations for In-Office Testing for additional information.
Are oral samples more sensitive than nasal samples when testing for Omicron and other recent variants of SARS-CoV-2?
As of now, no at-home antigen tests have been authorized by the FDA for use with oral samples, and there are no robust data suggesting that oral samples should be preferred over nasal samples for any SARS-CoV-2 variant.
How should I interpret home test results?
Home tests may be challenging to interpret because of the inability to verify the adequacy of the sample collection or that the testing procedures were performed correctly. Generally, because of the high specificity of these tests, any positive result should result in home isolation. If the pretest probability is low (eg, low community prevalence, no symptoms or exposures), confirmation of a positive home test with a NAAT such as a PCR test could be considered. In exposed or symptomatic patients, negative antigen tests should be repeated per FDA guidance.
Can at-home antigen tests be used in children younger than 2 years?
As of now, no at-home antigen tests have been authorized by the FDA for use in children younger than 2 years.
The scenarios below are intended to provide guidance for common clinical situations. Please see CDC testing guidance for further details. This guidance may change in the future as more data become available.
Scenario A. Patients with symptoms consistent with COVID-19
- Patients who have symptoms consistent with COVID-19 should be tested without delay. Given the ongoing spread of SARS-CoV-2 throughout the United States, a positive test (PCR or antigen) in a symptomatic patient should be taken as evidence of SARS-CoV-2 infection. Patients with positive test results should isolate per CDC guidance, staying home for a minimum of 5 days and wearing a mask around others for 10 days. Discussion of considerations for testing of patients with recently confirmed SARS-CoV-2 infection (within the prior 90 days) appears above.
- A symptomatic patient with a negative antigen test result may still have SARS-CoV-2 infection and should continue to isolate per CDC guidance. Further testing is required. A repeat antigen test 48 hours after the first test, per FDA guidance, or a PCR test should be performed.
- A symptomatic patient with a negative PCR test result (performed either as an initial test or as follow-up to a negative antigen test result) is unlikely to have SARS-CoV-2 infection but should still take precautions around others while symptomatic.
Scenario B. Patients who have close contact with individuals with confirmed or probable SARS-CoV-2 infection
- Asymptomatic patients with close contact exposure to an individual with confirmed or probable SARS-CoV-2 infection in the past 10 days should take precautions (wearing a high-quality mask around others, monitoring for symptoms of COVID-19 and minimizing contact with individuals at high risk for severe COVID-19) and should be tested for SARS-CoV-2 infection. Testing should occur at least 5 days after the exposure occurred. Discussion of considerations for testing of patients with recently confirmed SARS-CoV-2 infection (within the prior 90 days) appears above.
- If the test result (either antigen or PCR) is positive, the patient should be considered to have SARS-CoV-2 infection and should isolate immediately per CDC guidance, staying home for a minimum of 5 days and wearing a mask around others for 10 days.
- If the test result is negative, precautions should continue for the full 10 days. Negative antigen test results should be repeated twice (for a total of three tests) at 48-hour intervals per FDA guidance.
Interim Guidance Disclaimer: The COVID-19 clinical interim guidance provided here has been updated based on current evidence and information available at the time of publishing. Guidance will be regularly reviewed with regards to the evolving nature of the pandemic and emerging evidence. All interim guidance will be presumed to expire on June 30, 2023 unless otherwise specified.
American Academy of Pediatrics