Secondary household transmission of SARS-CoV-2 among children and adolescents: Clinical and epidemiological aspects.

OBJECTIVE: To evaluate the secondary attack rate (SAR) in children and adolescents, contacts of essential activities workers who were infected by SARS-CoV-2; and to describe associated clinical and epidemiological data. METHODS: A cross-sectional study conducted in children and adolescents aged 5 to 19 years of age, that were household contacts of parents and other relatives who were infected by SARS-CoV-2 in the city of Goiânia, Central Brazil, from March to October 2020. Sociodemographic and clinical data were collected from all participants. Nasopharyngeal and oropharyngeal swabs were collected and tested for SARS-CoV-2 RNA using real-time reverse transcription polymerase chain reaction (RT-PCR). Factors associated with SARS-CoV-2 infection and SAR were analyzed using Poisson regression. RESULTS: A total of 267 children and adolescents were investigated. The prevalence of SARS-CoV-2 RNA by the real-time RT-PCR test and/or the presence of COVID-19 associated symptoms (anosmia/ageusia and flu syndrome) was 25.1% (95.0% Confidence Interval [95.0% CI] = 20.3-30.6). More than half (55.1%) of the participants had sygns and symptoms. The most prevalent signs and symptoms in positive individuals were nasal congestion (62.7%), headache (55.2%), cough (50.8%), myalgia (47.8%), runny nose (47.8%), and anosmia (47.8%). The Poisson model showed that the following signs or symptoms were associated with SARS-CoV-2 infection: fever, nasal congestion, decreased appetite, nausea, anosmia, and ageusia. Families that had more than one infected adult, in addition to the index case, presented greater transmissibility to children and adolescents. CONCLUSIONS: Our results contribute to the hypothesis that children and adolescents are not important sources of transmission of SARS-CoV-2 in the home environment during a period of social distancing and school closure; even though they are susceptible to infection in the household (around » of our study population).

Molecular characterization of adenovirus detected from fecal samples obtained from children in the Central West region of Brazil.

The adenoviruses are frequently associated with sporadic gastroenteritis outbreaks in different parts of the world. This study aimed at the molecular characterization of human adenoviruses (HAdV) species and serotypes, in fecal samples from children, by multiplex-PCR and by PCR-RFLP, respectively, followed by genomic sequencing. Of 39 adenovirus-positive samples, 30 (76.9%) were classified as species F, six (15.4%) as species C, and two (5.1%) as species A, and one (2.6%) had a mixed F/C pattern. The serotyping showed that 14 (41.2%) were HAdV-41, 15 (44.1%) were HAdV-40, five (14.7%) were HAdV-5, and five samples could not be serotyped. This is the first study to molecularly characterize HAdV in the Central West region of Brazil, and the results highlight the circulation of the HAdV-5 among children with acute gastroenteritis in this region.