Recommended Isolation Period for COVID-19
The current recommended isolation period for COVID-19 is 5 days from symptom onset (or positive test if asymptomatic), followed by 5 days of mask wearing around others, provided symptoms are resolving and the person has been fever-free for at least 24 hours without fever-reducing medication 1.
Isolation Guidelines Based on Clinical Status
For Symptomatic Individuals
- Initial isolation period: 5 days from symptom onset
- Requirements to end isolation after 5 days:
- Symptoms must be resolving
- Must be fever-free for ≥24 hours without fever-reducing medications
- Should wear a well-fitting mask around others for an additional 5 days 2
For Asymptomatic Individuals
- Initial isolation period: 5 days from first positive test
- After isolation: Wear a well-fitting mask around others for an additional 5 days
- For athletes: 3 days of abstinence from training is recommended to ensure symptoms do not develop 3
Testing-Based Strategy Considerations
The decision to end isolation can be guided by two approaches:
- Time-based strategy: Ending isolation after a fixed period (5 days) if symptoms are resolving
- Test-based strategy: Using antigen tests to guide isolation decisions
When using antigen tests to guide isolation decisions:
- After 5-9 days, approximately 54.3% of individuals may still test positive on antigen tests 2
- Positive antigen test results are more likely:
- Earlier in the isolation period (day 5 vs. day 9)
- In symptomatic infections
- In those without previous infection or vaccination 2
Special Considerations
For Hospitalized Patients
According to WHO recommendations, hospital discharge criteria include:
- Normal temperature for >3 days without fever-reducing medications
- Significantly relieved respiratory symptoms
- Improved acute exudative lesions on chest CT
- Two consecutive negative RT-PCR tests with at least 1-day interval 3
For Immunocompromised Individuals
- Immunocompromised patients may require a multidisciplinary approach for discharge decisions 3
- These individuals may have prolonged viral shedding and potentially remain infectious for longer periods 4
Important Caveats
PCR vs. Infectiousness: A positive PCR test after the isolation period often represents persistent viral RNA shedding rather than ongoing infectiousness 1
- PCR tests can remain positive for up to 30 days after infection
- This does not necessarily indicate the person remains contagious
Risk of Shortened Isolation: Studies show that with a 10-day isolation period, the risk of releasing an individual who is still infectious is low (0-6.6%) 5
Household Transmission Risk: Among household contacts who were asymptomatic with negative tests through day 7, there was an 81% chance of remaining asymptomatic and negative through day 14 6
Mask Importance: During the 10 days after infection, persons might still be infectious to others and should wear a well-fitting mask when around others, even after ending isolation 2
Balancing Considerations
While longer isolation periods might further reduce transmission risk, they come with significant social, economic, and psychological costs. The 5+5 day approach (5 days isolation + 5 days masking) balances these concerns while maintaining reasonable protection against ongoing transmission 7.