Day by day symptoms following positive and negative PCR tests for SARS-CoV-2 in non-hospitalised health-care workers: a 90-day follow-up study

Background

Little is known about the long-term course of symptoms for mild coronavirus disease 2019 (COVID-19) when accounting for symptoms due to other causes. We aimed to compare symptoms day by day for non-hospitalised individuals who tested positive and negative with polymerase chain reaction for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2).

Methods

We followed 210 test-positive and 630 individually matched test-negative health-care workers of the Central Denmark Region up to 90 days after the test, April-June 2020. They daily reported seven COVID-19 related symptoms. Symptom courses were compared graphically and by conditional multivariable logistic regression.

Results

Thirty % of test-positive and close to zero of test-negative participants reported a reduced sense of taste and smell during all 90 days of follow-up (adjusted odds ratio [aOR] 86.07, 95% CI 22.86-323). Dyspnoea was reported by an initial 20% of test-positive with a gradual decline to about 5% after 30 days without ever reaching the level of the test-negative participants (aOR 6.88, 95% CI 2.41-19.63). Cough, headache, sore throat, muscle aches, and fever were temporarily more prevalent among the test positive participants, but after 30 days, no increases were seen. Women and participants aged 45 years or older tended to be more susceptible to SARS-CoV-2 infection.

Conclusion

Prevalence of long-lasting reduced sense of taste and smell is highly increased after being diagnosed with mild COVID-19. This pattern is also seen for dyspnoea at a low level but not for cough, sore throat, headache, muscle ache or pain, or fever.

Key messages

• Reduced sense of taste and smell is present at a highly increased level of 30% during 90 days after testing positive for severe acute respiratory syndrome coronavirus 2 (SARS-Cov-2).

• Test-positive participants experience dyspnoea persistently more often than test-negative participants but affect only few.

• The prevalence of cough, sore throat, headache, muscle ache or pain, and fever following a positive test reach the level seen after a negative test within 30 days.

• Women and participants aged 45 years or older tend to be more susceptible to symptoms following SARS-CoV-2 infection.