CDC Updates Transmission-Based Precautions, Duration of Isolation, and Return to Work Criteria
On July 17, the CDC posted substantial changes to the transmission-based precautions. As the CDC continues to learn more about the COVID-19 virus, the agency continues to revise prior guidance. The CDC updated the
Guidance that has been updated specific for healthcare settings includes:
- Except for rare situations, a test-based strategy is no longer recommended to determine when to discontinue transmission-based precautions for individuals who had tested positive for COVID-19
- For patients with severe to critical illness or who are severely immunocompromised, the recommended duration for transmission-based precautions was extended to 20 days after symptom onset (or, for asymptomatic severely immunocompromised patients, 20 days after their initial positive COVID-19 diagnostic test).
- Other symptom-based criteria were modified as follows:
- Changed from “at least 72 hours” to “at least 24 hours” have passed since last fever without the use of fever-reducing medications during the time-based time window.
- Changed from “improvement in respiratory symptoms” to “improvement in symptoms” to address expanding list of symptoms associated with COVID-19
- A summary of current evidence and rationale for these changes is described in a decision memo.
- For patients with COVID-19 illness, isolation and precautions can generally be discontinued 10 days after symptom onset and resolution of fever for at least 24 hours, without the use of fever-reducing medications, and with improvement of other symptoms.
- For persons who never develop symptoms, isolation and other precautions can be discontinued 10 days after the date of their first positive RT-PCR tests for COVID-19 RNA.
CDC provided recommendations for PCR testing to discontinue isolation precautions when time-based strategy is not used:
- For persons who are severely immunocompromised, a test-based strategy could be considered in consultation with infectious disease experts.
- For all others, a test-based strategy is no longer recommended except if providers want to discontinue isolation or precautions earlier than would occur under the time-based strategy outlined in in the duration of isolation precautions outlined above in consultation with infectious disease experts.
CDC provided recommendations for the role of the PCR testing after a person's COVID case has resolved and the discontinuation of isolation or precautions:
- For persons previously diagnosed with symptomatic COVID-19 who remain asymptomatic after recovery, retesting is not recommended within three months after the date of symptom onset for the initial COVID-19 infection. In addition, quarantine is not recommended in the event of close contact with an infected person.
- For persons who develop new symptoms consistent with COVID-19 during the three months after the date of initial symptom onset, if an alternative etiology cannot be identified by a provider, then the person may warrant retesting; consultation with infectious disease or infection control experts is recommended. Quarantine may be considered during this evaluation based on consultation with an infection control expert, especially in the event symptoms develop within 14 days after close contact with an infected person or based on other infectious agents causing the person's symptoms.
- For persons who never developed symptoms, the date of first positive RT-PCR test for SARS-CoV-2 RNA should be used in place of the date of symptom onset.
CDC outlined the role of serologic testing:
- Serologic testing should not be used to establish the presence or absence of COVID-19 infection or reinfection.
- Except in rare situations, test-based strategy is no longer recommended to determine when to allow healthcare personnel (HCP) to return to work.
- For HCP with severe to critical illness or who are severely immunocompromised, the recommended duration for work exclusion was extended to 20 days after symptom onset (or for asymptomatic severely immunocompromised HCP, 20 days after their initial positive COVID-19 diagnostic test).
- Other symptom-based criteria were modified as follows:
- Changed from “at least 72 hours” to “at least 24 hours” have passed since last fever without the use of fever-reducing medications.
- Changed from “improvement in respiratory symptoms” to “improvement in symptoms” to address expanding list of symptoms associated with COVID-19
- A summary of current evidence and rationale for these changes is described in a decision memo.
- 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
