SARS-CoV-2 viral clearance and viral load kinetics in young children (1-6 years) compared to adults: Results of a longitudinal study in Germany.

Objective: To investigate SARS-COV-2 viral clearance and viral load kinetics in the course of infection in children aged 1-6 years in comparison with adults. Methods: Prospective cohort study of infected daycare children and staff and their close contacts in households from 11/2020 to 06/2021. Adult participants took upper respiratory tract specimen from themselves and/or their children, for PCR tests on SARS-CoV-2. Data on symptoms and exposure were used to determine the date of probable infection for each participant. We determined (a) viral clearance, and (b) viral load dynamics over time. Samples were taken from day 4-6 to day 16-18 after diagnosis of the index case in the respective daycare group (5 samples per participant). Results: We included 40 children (1-6 years) and 67 adults (18-77 years) with SARS-CoV-2 infection. Samples were available at a mean of 4.3 points of time per participant. Among the participants, the 12-day study period fell in different periods within the individual course of infection, ranging from day 5-17 to day 15-26 after assumed infection.Children reached viral clearance at a median of 20 days after assumed infection (95% CI 17-21 days, Kaplan-Meier Analysis), adults at 23 days (95% CI 20-25 days, difference not significant). In both children and adults, viral load decreased over time with trajectories of the mean viral load not being statistically different between groups. Kaplan-Meier calculations show that from day 15 (95% CI 13-15), 50% of all participants had a viral load <1 million copies/ml, i.e. were no longer infectious or negative. Conclusion: Children aged 1-6 and adults infected with SARS-CoV-2 (wild type and Alpha variant) did not differ significantly in terms of viral load kinetics and time needed to clear the virus. Therefore, containment measures are important also in the daycare settings as long as the pandemic continues.

[Symptoms of SARS-CoV-2 infections in children of day care age]. / Symptomatik einer akuten SARS-CoV-2-Infektion bei Kindern im Kita-Alter.

Background: The symptoms of SARS-CoV­2 infections in children are mostly mild; however, the symptoms are highly variable. There are only a few studies on non-hospitalized children. The clinical picture described in hospitalized children cannot be transferred to non-hospitalized children and the frequency of certain symptoms in children may thus be overestimated. Furthermore, most studies include a broad age group (up to 18 years). The symptoms of younger children have so far been described in less detail. Objective: The paper aims to describe the frequency of COVID-19 symptoms in younger children (1-6 years old). Data of the two modules COALA (Corona: Anlassbezogene Untersuchungen in Kitas) and CATS (Corona-KiTa surveillance) of the Corona-KiTa study are evaluated and the results of the two studies are compared and discussed against the background of the different methodologies. In the COALA study, the type and frequency of symptoms of children infected with SARS-CoV­2 are evaluated and compared to symptoms of children who tested negative for SARS-CoV­2. Symptom frequencies of SARS-CoV­2 infected children of the COALA study are compared with data collected from surveillance data (CATS). Material and methods: The COALA study investigated 30 SARS-CoV­2 outbreaks in day care centers where at least 1 SARS-CoV­2 case was reported between October 2020 and June 2021. Using a prospective study design, day care children who were infected with SARS-CoV­2 and their contact persons were studied over a period of 12 days (including regular SARS-CoV­2 testing, retrospective interviews and daily symptom reporting). The results from the COALA study were compared with data from COVID-19 surveillance cases (CATS) for the same age group and time period. In Germany, SARS-CoV­2 cases are reported to the local health authorities by physicians and laboratories. When reporting cases symptoms can be reported as well. Results: From the COALA study, interview and reported symptom data were available for 289 children from the participating day care centers. Of 39 children with a SARS-CoV­2 infection (wild-type, α­variant), 64% had at least 1 symptom; of the children who tested negative for SARS-CoV­2, 40% had at least 1 symptom. In both groups, rhinitis was the most common symptom (36% vs. 25%, n. s.). From the surveillance data (CATS), clinical information was available for 84,371 SARS-CoV­2 positive children; fever was most common (27%) along with rhinitis (26%). Severe symptoms such as dyspnea were rarely reported in the outbreak investigations and in the surveillance data (3% and 1%, respectively). Conclusion: Day care-aged children infected with SARS-CoV­2 usually have mild or asymptomatic courses. Their symptoms are similar to those of children who tested negative for SARS-CoV­2 from the same day care centers; thus, the observed COVID-19 symptoms are nonspecific. Combining data from the two modules is useful: findings from a very large database, as provided by the surveillance data, are complemented by findings from day care center outbreaks, where detailed prospective data on infected children can be compared with those of children who tested negative for SARS-CoV­2.

Symptomatik einer akuten SARS-CoV-2-Infektion bei Kindern im Kita-Alter Symptoms of SARS-CoV-2 infections in children of day care age

Hintergrund Die Symptomatik einer pädiatrischen SARS-CoV-2-Infektion ist sehr variabel. Es gibt nur wenige Studien zu nichthospitalisierten Kindern bzw. Kindern im Kita-Alter. Ziel der Arbeit Die Arbeit soll die Häufigkeit verschiedener COVID-19-Symptome bei ein- bis 6‑jährigen Kindern beschreiben. Sie führt dazu Daten aus 2 Modulen der Corona-KiTa-Studie zusammen: 1) das Modul „COALA“ – Corona: Anlassbezogene Untersuchungen in Kitas und 2) das Modul „CATS“ – Corona KiTa Surveillance (Meldedaten). Material und Methoden In COALA wurden die Infektionsgeschehen in 30 Kitas, in denen ein SARS-CoV-2-Fall gemeldet wurde, untersucht (Oktober 2020 bis Juni 2021). Kita-Kinder wurden prospektiv über 12 Tage beobachtet (SARS-CoV-2-Tests, Symptomtagebuch). Die Ergebnisse wurden mit den Symptomangaben der deutschlandweit gemeldeten SARS-CoV-2-Fälle (Meldedaten) verglichen. Ergebnisse Aus den teilnehmenden Kitas liegen für 289 Kinder Angaben vor. Von 39 Kindern mit SARS-CoV‑2 (Wildtyp, α‑Variante) hatten 64 % mindestens ein Symptom, von den nicht mit SARS-CoV‑2 infizierten Kindern 40 %. In beiden Gruppen war Schnupfen das häufigste Symptom (36 % vs. 25 %, n. s.). Aus den Meldedaten liegen für 84.371 Kinder klinische Informationen vor, Fieber war am häufigsten (27 %), neben Schnupfen (26 %). Schwere Beschwerden wie z. B. Atemnot wurden in den Ausbruchsuntersuchungen und in den Meldedaten nur selten angegeben (3 % bzw. 1 %). Schlussfolgerung Kinder im Kita-Alter haben meist milde bzw. asymptomatische Verläufe einer SARS-CoV-2-Infektion. Ihre Symptome ähneln denjenigen von nicht mit SARS-CoV‑2 infizierten Kindern aus denselben Kitas. Es erscheint sinnvoll, Erkenntnisse aus den Meldedaten durch Ausbruchsuntersuchungen zu ergänzen, um methodische Limitationen der einzelnen Vorgehensweisen auszugleichen. Zusatzmaterial online Die Online-Version dieses Beitrags (10.1007/s00112-022-01640-3) enthält eine weitere Tabelle, die Symptome bei symptomatischen SARS-CoV-2-Fällen von Kindern im Alter von einem bis 6 Jahren in der COALA-Stichprobe und in den Meldedaten gegenüberstellt.

Transmission of SARS-CoV-2 among children and staff in German daycare centres.

In daycare centres, the close contact of children with other children and employees favours the transmission of infections. The majority of children <6 years attend daycare programmes in Germany, but the role of daycare centres in the SARS-CoV-2 pandemic is unclear. We investigated the transmission risk in daycare centres and the spread of SARS-CoV-2 to associated households. 30 daycare groups with at least one recent laboratory-confirmed SARS-CoV-2 case were enrolled in the study (10/2020-06/2021). Close contact persons within daycare and households were examined over a 12-day period (repeated SARS-CoV-2 PCR tests, genetic sequencing of viruses, symptom diary). Households were interviewed to gain comprehensive information on each outbreak. We determined primary cases for all daycare groups. The number of secondary cases varied considerably between daycare groups. The pooled secondary attack rate (SAR) across all 30 daycare centres was 9.6%. The SAR tended to be higher when the Alpha variant was detected (15.9% vs. 5.1% with evidence of wild type). The household SAR was 53.3%. Exposed daycare children were less likely to get infected with SARS-CoV-2 than employees (7.7% vs. 15.5%). Containment measures in daycare programmes are critical to reduce SARS-CoV-2 transmission, especially to avoid spread to associated households.

Health behaviour and COVID-19: Initial findings on the pandemic.

The COVID-19 pandemic poses new challenges to both individuals and societies that impact health behaviour in many ways. This narrative review brings together initial findings for smoking, alcohol use, nutrition, physical activity and obesity. Smoking and obesity are potential direct risk factors for a severe course of COVID-19, and alcohol abuse, physical inactivity and an unbalanced diet can be indirect risk factors. The constraints of public life to contain the COVID-19 pandemic reduced the opportunities for physical activity and sports, although the initial results on physical activity during this period for Germany do not reflect this assumption. While a part of the population reports making healthier diet choices than before the pandemic, others do not. For smoking and risky alcohol use, data at an aggregate level for the general population do not indicate any behaviour changes. However, different trends appear to be emerging for different population groups pointing to the fact that social inequalities in pandemic-related changes to health behaviour must be assumed. Should further studies confirm these results, this would indicate a need for pandemic-specific prevention measures. Furthermore, specifically during the pandemic, prevention and health promotion measures directed at changes to health behaviour should continue to be implemented and adapted to the restrictions due to the pandemic. Equity in health should be promoted in particular.

SARS-CoV-2 Transmissibility Within Day Care Centers-Study Protocol of a Prospective Analysis of Outbreaks in Germany.

Introduction: Until today, the role of children in the transmission dynamics of SARS-CoV-2 and the development of the COVID-19 pandemic seems to be dynamic and is not finally resolved. The primary aim of this study is to investigate the transmission dynamics of SARS-CoV-2 in child day care centers and connected households as well as transmission-related indicators and clinical symptoms among children and adults. Methods and Analysis: COALA ("Corona outbreak-related examinations in day care centers") is a day care center- and household-based study with a case-ascertained study design. Based on day care centers with at least one reported case of SARS-CoV-2, we include one- to six-year-old children and staff of the affected group in the day care center as well as their respective households. We visit each child's and adult's household. During the home visit we take from each household member a combined mouth and nose swab as well as a saliva sample for analysis of SARS-CoV-2-RNA by real-time reverse transcription polymerase chain reaction (real-time RT-PCR) and a capillary blood sample for a retrospective assessment of an earlier SARS-CoV-2 infection. Furthermore, information on health status, socio-demographics and COVID-19 protective measures are collected via a short telephone interview in the subsequent days. In the following 12 days, household members (or parents for their children) self-collect the same respiratory samples as described above every 3 days and a stool sample for children once. COVID-19 symptoms are documented daily in a symptom diary. Approximately 35 days after testing the index case, every participant who tested positive for SARS-CoV-2 during the study is re-visited at home for another capillary blood sample and a standardized interview. The analysis includes secondary attack rates, by age of primary case, both in the day care center and in households, as well as viral shedding dynamics, including the beginning of shedding relative to symptom onset and viral clearance. Discussion: The results contribute to a better understanding of the epidemiological and virological transmission-related indicators of SARS-CoV-2 among young children, as compared to adults and the interplay between day care and households.

[SARS-CoV-2 incidence, transmission, and containment measures in daycare centers during the COVID-19 pandemic-findings from the Corona Daycare Study]. / Infektionsgeschehen und Eindämmungsmaßnahmen in Kitas während der COVID-19-Pandemie ­ Erkenntnisse aus der Corona-KiTa-Studie.

BACKGROUND: Daycare centers are of substantial sociopolitical and pedagogical relevance; at the same time, the close contact of children in daycare groups among each other and with employees favors the transmission of infections. In the COVID-19 pandemic, questions arose about how infection events occur in daycare centers, what role daycare children play in the pandemic, and what protective and hygienic measures are implemented in daycare centers. From 06/2020 to 12/2021, we conducted the "Corona Day Care Study," in which we address pedagogical and infection epidemiological topics in a joint approach. METHODS: In the study, data are collected from different sources. Official reporting data as well as weekly data from daycare centers in the so-called KiTa Register are continuously evaluated. In addition, SARS-CoV­2 outbreaks in daycare centers are investigated on site by repeated sample collection and interviews. RESULTS: SARS-CoV­2 infection incidence in daycare centers or in daycare-aged children was very dynamic from 03/2020 to 05/2021. In the second and third pandemic waves, the number of SARS-CoV­2 outbreaks in daycare centers rose sharply, accompanied by a substantial increase in daycare and group closures. Most recently, the proportion of affected children in outbreaks increased steadily. However, preliminary examinations of SARS-CoV­2 outbreaks (n = 28) revealed that, on average, only a fraction of daycare contact persons (6.8%) were infected by child index cases. Transmission frequencies differed markedly between the individual daycare centers. DISCUSSION: The combination of regularly collected reporting and survey data as well as outbreak investigations allows a multilayered monitoring and understanding of infection events in daycare centers; its findings could be incorporated into recommendations for public health measures.