question: If a previously infected person has clinically recovered but later experiences symptoms consistent with COVID-19, should the person be isolated again and tested for SARS-CoV-2?
answer: If a previously infected person experiences new symptoms consistent with COVID-19 3 months or more after the date of the previous illness onset (or date of last positive viral diagnostic test [RT-PCR or antigen test] if the person never experienced symptoms), the person should undergo repeat viral diagnostic testing. However, serologic testing should not be used to establish the presence or absence of SARS-COV-2 infection or reinfection. These people who have a positive test result should be considered infectious and remain isolated until they again meet criteria for discontinuation of isolation or of transmission-based precautions. Contact tracing during the person’s second episode of symptoms is warranted. For persons who have recovered from laboratory-confirmed SARS-CoV-2 infection and who experience new symptoms consistent with COVID-19 within 3 months since the date of symptom onset of the previous illness episode (or date of last positive viral diagnostic test if the person never experienced symptoms), repeating viral diagnostic testing may be warranted if alternative etiologies for the illness cannot be identified. If reinfection is suspected and retesting is undertaken, the person should follow isolation recommendations for cases of COVID-19 pending clinical evaluation and testing results. Results of repeat testing should also be interpreted in consultation with an infectious disease specialist with consideration of cycle threshold values (if available) and clinical presentations. The determination of whether a patient with a subsequently positive test is contagious to others should be made on a case-by-case basis, in consultation with infectious diseases specialists and/or public health authorities, after review of available information (e.g., medical history, time from initial positive test, RT-PCR Ct values, and presence of COVID-19 signs or symptoms). Note: Serologic testing should not be used to establish the presence or absence of SARS-CoV-2 infection or reinfection.