Correction: Where is the greatest risk of COVID-19 infection? Findings from Germany's largest public health department, Cologne.

[This corrects the article DOI: 10.1371/journal.pone.0273496.].

Impact of physical activity on COVID-19-related symptoms and perception of physical performance, fatigue and exhaustion during stay-at-home orders.

Objectives: The measures used to contain the COVID-19 pandemic led to a significant reduction in physical activity. Due to the health benefits of exercise, recommendations were made for lockdown restrictions. Within the CoCo-Fakt study (Cologne-Corona counselling and support for index and contacts during the quarantine period), we aimed to determine how these recommendations were implemented, especially by individuals who were officially quarantined due to an infected persons (IPs) or as close contacts (CPs), and how this affected their physical and psychological condition. Methods: From 12 December 2020 to 6 January 2021, all IPs and CPs registered by Cologne's public health department up to the survey period were surveyed online. Of 10 547 people in the CoCo-Fakt sample, 8102 were integrated into the current analysis. In addition to demographic data, information regarding COVID-19-specific and persistent symptoms or conditions and their association with the amount and type of exercise and screen time before and during the quarantine were collected. Results: Before quarantine, 66.9% of IPs and 69% of CPs were physically active; during quarantine, this decreased by 49.4% in IPs depending on the course of the disease and by 30.6% in CPs. Physically active IPs and CPs felt less exhausted and more fit during their quarantine periods than those who were inactive, with active IPs significantly less likely to report prolonged physical and psychological symptoms than their more sedentary counterparts. Conclusion: Given the acute and long-term positive effects of exercise on quarantined individuals, corresponding recommendations should be communicated to those affected, especially CPs. Recommendations for IPs depend on their health status.

Where is the greatest risk of COVID-19 infection? Findings from Germany's largest public health department, Cologne.

BACKGROUND: SARS-CoV-2 has been spreading worldwide since late 2019. Before vaccines became available, exclusively non-pharmaceutical measures were used to prevent transmission of infection. Despite the fact that vaccinations are now available, it is still important to identify relevant transmission routes in order to contain the COVID-19- or further pandemics. Therefore, this study aims to systematically analyse data from the largest public health department in Germany to determine the significance of the various known and unknown transmission situations in terms of the proportion of infections. METHODS: All infections in Cologne were systematically recorded by the local health department. In addition to clinical data, the transmission situations were recorded and categorised as pertaining to social contact, work contact, travellers, health care workers, users of educational institutions, visitors of community institutions, infection in the context of medical treatment, and unknown infection. FINDINGS: The analysis included 25,966 persons. A transmission situation could be identified in 82.7% of the cases (n = 21,477). Most persons (42.1%) were infected due to social contact, primarily within their own household. Another 22.3% were infected at their place of work; this was particularly common among staff members of medical facilities, nursing homes and educational institutions. In 17.3% of the cases, the transmission situation remained unknown; the cases with unknown transmission situation were slightly more often symptomatic (75.2%) than the cases with known transmission situation (69.4%). INTERPRETATION: Considering that during the study period the leading strains were the wild-type and alpha-variant transmission rather occurred during scenarios involving close contacts than in anonymous situations. Presumably, however, the findings can be transferred to the new variants. Therefore, in order to prevent transmission, besides vaccination regular antigen tests and/or appropriate protective measures remain relevant until this pandemic has subsided.

Changes in Alcohol Consumption, Eating Behaviors, and Body Weight during Quarantine Measures: Analysis of the CoCo-Fakt Study.

INTRODUCTION: Public health measures enacted to reduce COVID-19 transmission have affected individuals' lifestyles, mental health, and psychological well-being. To date, little is known how stay-at-home orders have influenced the eating behaviors, weight development, and alcohol consumption of quarantined persons. The CoCo-Fakt cohort study analyzed these parameters and their association with psychological distress and coping strategies. METHODS: An online survey was conducted of all persons who tested positive for SARS-CoV-2 (infected persons [IP]) between December 12, 2020, and January 6, 2021, as well as their close contacts (contact persons [CP]) registered by the public health department of Cologne. 8,075 of 33,699 individuals were included in the analysis. In addition to demographic data, psychological distress, and coping strategies, information on changes in body weight, eating, and drinking behaviors was collected. RESULTS: IP lost 1.2 ± 4.4 kg during the quarantine period, and CP gained 1.6 ± 4.1 kg. The reasons given by IP for weight change were mainly loss of taste and feeling sick, whereas CP were more likely than IP to eat out of boredom. Higher psychological burden and lower coping strategies were associated with both weight gain and loss. Of the 30.8% of participants who changed their alcohol consumption during the quarantine period, CP in particular drank more alcohol (IP 15.2%; CP 47.7%). Significantly less alcohol was consumed by individuals with higher coping scores. CONCLUSION: In this short but psychologically stressful period of stay-at-home orders, changes in eating and drinking behavior as well as weight development are evident, mainly in high-risk contacts. To avoid possible long-term sequelae, health authorities should take these findings into account during the quarantine period; in particular, general practitioners should consider these findings during follow-up.

How to manage quarantine-adherence, psychosocial consequences, coping strategies and lifestyle of patients with COVID-19 and their confirmed contacts: study protocol of the CoCo-Fakt surveillance study, Cologne, Germany.

INTRODUCTION: The current coronavirus (SARS-CoV-2) pandemic has placed unprecedented restrictions on people's lives and routines. To counteract the exponential spread of this virus, a lockdown was implemented in Germany in March 2020. Infected persons and their contacts were also quarantined. Compliance with quarantine measures is essential for containing the spread of the virus and avoiding incalculable consequences in terms of morbidity and mortality. On the other hand, prolonged homestays, particularly quarantining, may lead to fear, panic, anxiety and depression. Hence, determining the psychological response in people during quarantine and their coping strategies is relevant for the counselling and support of affected persons by healthcare workers. METHODS AND ANALYSIS: The CoCo-Fakt-Survey (Cologne-Corona-Beratung und Unterstützung Für Index- und KontAKt-Personen während der Quarantäne-ZeiT; Cologne-Corona counselling and support for index and contacts during the quarantine period-author's translation) will examine a cohort of persons in Cologne quarantined since the beginning of the SARS-CoV-2 outbreak during March 2020. The questionnaire will include demographic data, transmission route, health status, knowledge of and adherence to quarantine measurements, psychological impact on individuals and their family members including children, mental health status, and lifestyle (physical activity/sedentary behaviour, relaxation techniques, nutrition, smoking). All Cologne residents who needed to be quarantined due to a coronavirus infection and the individuals with whom they had contact will be surveyed. ETHICS AND DISSEMINATION: No risks have been identified and no complications are expected. Ethics approval was obtained from the Rheinisch-Westfälische Technische Hochschule (RWTH) Aachen Human Ethics Research Committee (351/20), and the research will be conducted in accordance with the approved protocol. The results will be disseminated through peer-reviewed journals and social medicine conferences.