Day care study showed no differences in long-term symptoms in children who were and were not infected during COVID-19 outbreaks

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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.Peer Reviewe

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.Peer Reviewe

Ageing of the retinal pigment epithelium: implications for transplantation

This review will discuss some of the implications for using cells from aged donors for retinal pigment epithelium (RPE) transplantation. It will consider age-related changes in the structure and function of RPE cells and the accumulation of potentially damaging photoreactive constituents. The review will focus on the role of the ocular pigments lipofuscin and melanin in respect to age-related changes in composition, photoreactivity and potential role in retinal ageing and age-related macular degeneration. The article concludes by considering the suitability of senescent RPE cells for transplantation and whether such cells can be rejuvenated

The photoreactivity of ocular lipofuscin

Lipofuscin or “age pigment” is a lipid–protein complex which accumulates in a variety of postmitotic, metabolically active cells throughout the body. These complexes, which are thought to result from the incomplete degradation of oxidised substrate, have the potential for photoreactivity. This is particularly so in the retina in which the lipofuscin not only contains retinoid metabolites but is also exposed to high oxygen and fluxes of visible light all of which provide an ideal environment for the generation of reactive oxygen species (ROS). Lipofuscin is a potent photoinducible generator of ROS with the potential to damage proteins, lipids and DNA. Retinal cell dysfunction may be strongly associated with photoreactivity of lipofuscin and may contribute to age-related disease and vision loss

A scalable, clinically severe pig model for Duchenne muscular dystrophy

Large animal models for Duchenne muscular dystrophy (DMD) are crucial for evaluation of diagnostic procedures and treatment strategies. Pigs cloned from male cells lacking DMD exon 52 (DMDΔ52) resemble molecular, clinical and pathological hallmarks of DMD, but die before sexual maturity and cannot be propagated by breeding. Therefore, we generated female DMD+/- carriers. A single founder animal had 11 litters with 29 DMDY/-, 34 DMD+/- as well as 36 male and 29 female wild-type offspring. Breeding with F1 and F2 DMD+/- carriers resulted in additional 114 DMDY/- piglets. With intensive neonatal management, the majority survived for 3-4 months, providing statistically relevant cohorts for experimental studies. Pathological investigations and proteome studies of skeletal muscles and myocardium confirmed the resemblance of human disease mechanisms. Importantly, DMDY/- pigs reveal progressive myocardial fibrosis and increased expression of connexin-43, associated with significantly reduced left ventricular ejection fraction already at age 3 months. Furthermore, behavioral tests provided evidence for impaired cognitive ability. Our breeding cohort of DMDΔ52 pigs and standardized tissue repositories provide important resources for studying DMD disease mechanisms and for testing novel treatment strategies

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.Background The symptoms of SARS-CoV‑2 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-CoV‑2 are evaluated and compared to symptoms of children who tested negative for SARS-CoV‑2. Symptom frequencies of SARS-CoV‑2 infected children of the COALA study are compared with data collected from surveillance data (CATS). Material and methods The COALA study investigated 30 SARS-CoV‑2 outbreaks in day care centers where at least 1 SARS-CoV‑2 case was reported between October 2020 and June 2021. Using a prospective study design, day care children who were infected with SARS-CoV‑2 and their contact persons were studied over a period of 12 days (including regular SARS-CoV‑2 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-CoV‑2 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-CoV‑2 infection (wild-type, α‑variant), 64% had at least 1 symptom; of the children who tested negative for SARS-CoV‑2, 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-CoV‑2 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-CoV‑2 usually have mild or asymptomatic courses. Their symptoms are similar to those of children who tested negative for SARS-CoV‑2 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-CoV‑2.Peer Reviewe