The presence of symptoms within 6 months after COVID-19: a single-center longitudinal study.

BACKGROUND: Characterizing the post-COVID health conditions is helpful to direct patients to appropriate healthcare. AIMS: To describe the presence of symptoms in COVID-19 patients within 6 months after diagnosis and to investigate the associated factors in terms of reporting symptoms. METHODS: Data of DEU-COVIMER (a telephone interview-based COVID-19 follow-up center established in a tertiary care hospital) was analyzed for SARS-CoV-2 RNA positive participants aged ≥ 18 years from November 1st, 2020, to May 31st, 2021. Symptom frequencies were stratified by demographic and clinical characteristics at one, three, and 6 months after diagnosis. With the patients who had symptoms at baseline, generalized estimating equations were applied to identify the factors associated with reporting of symptoms. RESULTS: A total of 5610 patients agreed to participate in the study. Symptom frequency was 37.2%, 21.8%, and 18.2% for the first, third, and sixth months. Tiredness/fatigue, muscle or body aches, and dyspnea/difficulty breathing were the most common symptoms in all time frames. In multivariate analysis, older age, female gender (odds ratio OR 1.74, 95% confidence interval 1.57-1.93), bad economic status (OR 1.37, 1.14-1.65), current smoking (OR 1.15, 1.02-1.29), being fully vaccinated before COVID-19 (OR 0.53, 0.40-0.72), having more health conditions (≥ 3 conditions, OR 1.78, 1.33-2.37), having more symptoms (> 5 symptoms, OR 2.47, 2.19-2.78), and hospitalization (intensive care unit, OR 2.18, 1.51-3.14) were associated with reporting of symptoms. CONCLUSIONS: This study identifies risk factors for patients who experience post-COVID-19 symptoms. Healthcare providers should appropriately allocate resources prioritizing the patients who would benefit from post-COVID rehabilitation.

Transmission dynamics and timing of key events for SARS-CoV-2 infection in healthcare workers.

BACKGROUND: Healthcare workers (HCWs) have increased risk for SARS-CoV-2 infection via contacts in hospitals, as well as via transmission in the community. Serial interval, which is defined as the time between symptom onsets in an infector-infectee pair, and the incubation period are key parameters in determining the control strategies for COVID-19. This study aimed to evaluate surveillance of HCWs and estimate the serial interval and incubation period of COVID-19. METHODS: A total of 149 HCWs and 36 certain infector-infectee pairs between 19th March 2020 and 1st November 2020 in a university hospital were included in the study. Epidemiological characteristics were recorded. Serial interval and incubation period were estimated using parametric accelerated failure time models. RESULTS: Forty HCWs (26.8%) were detected via contact-based surveillance. Of 100 HCWs epidemiologically linked with a confirmed COVID-19 case, 36 (36%) had contact with a colleague. The median serial interval was 3.93 days (95% CI: 3.17-4.83). Of symptomatic HCWs, 97.5% had developed symptoms 13.71 (95% CI: 9.39-18.73) days after symptom onset of the primary case. The median incubation period was 3.99 (95% CI: 3.25-4.84) days. Of symptomatic HCWs, 97.5% developed symptoms within 9.49 (95% CI: 6.75-12.20) days after infection. CONCLUSIONS: The serial interval and the incubation period of COVID-19 in HCWs were shorter than in the general population. Rigorous contact tracing and isolation of infected HCWs could have resulted in shorter serial intervals. Implementation of more stringent in-hospital control measures focussed on transmission between HCWs should be considered.