For persons who remain asymptomatic following recovery from COVID-19, retesting (e.g., as part of a contact tracing investigation) is not necessary during the first 3 months after the date of symptom onset. When a positive test occurs less than 3 months after the person’s symptom onset of their most recent illness, it is possible that the positive test represents a new infection or a persistently positive test associated with the previous infection. If a positive test occurs more than 3 months after a person’s symptom onset, clinicians and public health authorities should consider the possibility of reinfection. Until we have more information, the determination of whether a patient with a positive test in these situations is contagious to others should be made on a case-by-case basis. Consider consultation with infectious disease specialists and public health authorities to review all available information (e.g., medical history, time from an initial positive test, RT-PCR Ct values, and presence of COVID-19 signs or symptoms). Persons who are determined to be potentially infectious should undergo an evaluation and remain isolated until they again meet the criteria for discontinuation of isolation or discontinuation of transmission-based precautions, depending on their circumstances.