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July 22, 2020

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  • Adopt new CDC guidance for the discontinuation of Transmission-Based Precautions (TBP) for patients diagnosed with COVID-19.
  • Adopt new CDC guidance for allowing Healthcare Personnel (HCP) to Return to Work (RTW) following COVID-19 infection.

Summary of CDC guidance: Discontinue the use of "test-based" strategies for the
discontinuation of TBP for patients infected with COVID-19

A test-based strategy is no longer recommended (except as noted below*) because, in the majority of cases, it results in prolonged isolation of patients who continue to shed detectable SARS-CoV-2 RNA but are no longer infectious.

Symptom-Based Strategy for Discontinuing Transmission-Based Precautions.
Patients with mild to moderate illness who are not severely immunocompromised:

  • At least 10 days have passed since symptoms first appeared and
  • At least 24 hours have passed since last fever without the use of fever-reducing medications and
  • Symptoms (e.g., cough, shortness of breath) have improved

Note: For patients who are not severely immunocompromised and who were asymptomatic throughout their infection, TBP may be discontinued when at least 10 days have passed since the date of their first positive viral diagnostic test.

Patients with severe to critical illness or who are severely immunocompromised:

  • At least 20 days have passed since symptoms first appeared and
  • At least 24 hours have passed since last fever without the use of fever-reducing medications and
  • Symptoms (e.g., cough, shortness of breath) have improved

Note: For severely immunocompromised patients who were asymptomatic throughout their infection, TBP may be discontinued when at least 20 days have passed since the date of their first positive viral diagnostic test.

*In some instances, a test-based strategy could be considered for discontinuing Transmission-based Precautions earlier than if the symptom-based strategy were used. However, as described in the Decision Memo, many individuals will have prolonged viral shedding, limiting the utility of this approach. A test-based strategy could also be considered for some patients (e.g., those who are severely immunocompromised) in consultation with local infectious diseases experts  if concerns exist for the patient being infectious for more than 20 days

Summary of CDC guidance: Discontinue the use of "Test-Based" strategies for the
criteria for HCP to RTW after COVID-19 infection

A test-based strategy is no longer recommended (except as noted below*) because, in the majority of cases, it results in excluding from work HCP who continue to shed detectable SARS-CoV-2 RNA but are no longer infectious.

Return to Work Criteria for HCP with SARS-CoV-2 Infection: Symptom-based strategy for determining when HCP can return to work.

HCP with mild to moderate illness who are not severely immunocompromised:

  • At least 10 days have passed since symptoms first appeared and
  • At least 24 hours have passed since last fever without the use of fever-reducing medications and
  • Symptoms (e.g., cough, shortness of breath) have improved

Note:  HCP who are not severely immunocompromised and were asymptomatic throughout their infection may return to work when at least 10 days have passed since the date of their first positive viral diagnostic test.

HCP with severe to critical illness or who are severely immunocompromised:

  • At least 20 days have passed since symptoms first appeared and
  • At least 24 hours have passed since last fever without the use of fever-reducing medications and
  • Symptoms (e.g., cough, shortness of breath) have improved

Note:  HCP who are severely immunocompromised but who were asymptomatic throughout their infection may return to work when at least 20 days have passed since the date of their first positive viral diagnostic test.

*In some instances, a test-based strategy could be considered to allow HCP to return to work earlier than if the symptom-based strategy were used. However, as described in the Decision Memo, many individuals will have prolonged viral shedding, limiting the utility of this approach. A test-based strategy could also be considered for some HCP (e.g., those who are severely immunocompromised) in consultation with local infectious diseases experts if concerns exist for the HCP being infectious for more than 20 days.


Available evidence indicates that concentrations of SARS-CoV-2 RNA measured in upper respiratory specimens decline after onset of symptoms. Along with decreasing RNA concentrations, the likelihood of recovering replication-competent virus also declines after onset of symptoms. For patients with mild to moderate COVID-19, replication-competent virus has not been recovered after 10 days following symptom onset. Some persons with severe COVID-19 have had recovery of replication-competent virus between 10 and 20 days after symptom onset; this accounts for the longer timeframe for these individuals in the new recommendation. Further, a large contact tracing study demonstrated that high-risk household and hospital contacts did not develop infection if their exposure to a case patient started 6 days or more after the case patient’s illness onset.

Despite the inability to isolate replication-competent virus 3 weeks after symptom onset, recovered patients can continue to have SARS-CoV-2 RNA detected in their upper respiratory specimens for up to 12 weeks. An additional study did not detect replication-competent virus specimens from patients who recovered from an initial COVID-19 illness and subsequently developed new symptoms and retested positive by RT-PCR. Finally, 6 months after the emergence of SARS-CoV-2, there have been no confirmed cases of SARS-CoV-2 reinfection. Adapting the new CDC guidance will limit unnecessary prolonged isolation and unnecessary use of laboratory testing resources.