Household Transmission of SARS-CoV-2 and Long-term Immunity in Children: A Prospective Study in Northern Spain.

BACKGROUND: The role of children in SARS-CoV-2 transmission and their immune response after infection have been profoundly discussed. Hereby, we analyze both aspects in a Spanish pediatric population. METHODS: Prospective, multicentre, longitudinal study performed from July 2020 to September 2021 in children up to 14 years old. Venous blood samples were collected every 6 months and serum was analyzed for antibodies against SARS-CoV-2 using a spike (S) and a nucleocapsid (N) protein assays. Household contacts of seropositive children were tested. Household transmission, antibody dynamics, and durability were analyzed. RESULTS: Two hundred children were recruited and 28 had SARS-CoV-2 antibodies at the end of the study, resulting in an overall seroprevalence of 16.6% (95% CI: 9.5%-19.6%). Most of children (18/28) were secondary cases. The secondary attack rate (SAR) was lower in households with pediatric index cases than in those with adult index cases ( P = 0.023). The median antibody titers in the first positive serology, for the seropositive patients, were 137 BAU/mL (IQR 83.3-427.4) for the S-assay and 132.5 COI (IQR 14.5-170.5) for the N-assay without significant differences between symptomatic and asymptomatic children. The median time between the RT-PCR and the last serology was 7.5 months (IQR 5.2-8.8), and the duration of SARS-CoV-2 antibodies after infection was proven to be at least 18 months. There were no cases of seroreversion. CONCLUSIONS: (1) Children are not the main drivers of SARS-CoV-2 household transmission. (2) They maintain SARS-CoV-2 antibodies for up to 18 months after infection and the titers are similar between symptomatic and asymptomatic children.

Use of antibiotics in Paediatric Primary Health Care before and during the COVID-19 pandemic Consumo de antibióticos en pediatría de atención primaria antes y durante la pandemia de COVID-19

Introduction Consumption of antibiotics is high in Spain, primarily in children. Excessive use of then contributes to the development of antimicrobial resistance. The aim of our study is to analyse the evolution of antibiotic consumption at the Primary Health Care in the paediatric population of Asturias, Spain, from 2014 to 2021, and to evaluate the impact of COVID-19 pandemic on it. Methods Retrospective and observational study using data about antibacterial agents for systemic use dispensed for official prescriptions to children under 14 years in Primary Care. Antibiotic consumption is expressed as defined daily dose (DDD) per 1000 inhabitants per day (DID). Results The antibiotic consumption rate dropped from 13.9 DID in 2014 to 4.0 in 2021 (β = -1,42, p = 0,002), with and inflection point in 2019. From 2019 to 2020 antibiotic use dropped by 47.1%. Antibiotic consumption remained very low from April 2020 to September 2021, and then moderately increased from October 2021. Prevalence of antibiotic use dropped from 39.9% in 2014 to 17.5% in 2021 (β = -3,64, p = 0,006). Relative consumption of amoxicillin/clavulanic acid decreased, while those of amoxiciline and third-generation cephalosporins increased. Conclusions Paediatric antibiotic consumption collapsed in Asturias in 2020, coinciding with COVID-19 pandemic. Monitoring of antimicrobial usage indicators will allow to check if these changes are sustained over time.

Use of antibiotics in Paediatric Primary Health Care before and during the COVID-19 pandemic.

INTRODUCTION: Consumption of antibiotics is high in Spain, primarily in children. Excessive use of then contributes to the development of antimicrobial resistance. The aim of our study is to analyse the evolution of antibiotic consumption at the Primary Health Care in the paediatric population of Asturias, Spain, from 2014 to 2021, and to evaluate the impact of COVID-19 pandemic on it. METHODS: Retrospective and observational study using data about antibacterial agents for systemic use dispensed for official prescriptions to children under 14 years in Primary Care. Antibiotic consumption is expressed as defined daily dose (DDD) per 1000 inhabitants per day (DID). RESULTS: The antibiotic consumption rate dropped from 13.9 DID in 2014 to 4.0 in 2021 (ß=-1,42, p=0,002), with and inflection point in 2019. From 2019 to 2020 antibiotic use dropped by 47.1%. Antibiotic consumption remained very low from April 2020 to September 2021, and then moderately increased from October 2021. Prevalence of antibiotic use dropped from 39.9% in 2014 to 17.5% in 2021 (ß=-3,64, p=0,006). Relative consumption of amoxicillin/clavulanic acid decreased, while those of amoxiciline and third-generation cephalosporins increased. CONCLUSIONS: Paediatric antibiotic consumption collapsed in Asturias in 2020, coinciding with COVID-19 pandemic. Monitoring of antimicrobial usage indicators will allow to check if these changes are sustained over time.

Variation in SARS-CoV-2 seroprevalence in children in the region of Asturias, Northern Spain.

BACKGROUND: Updated seroprevalence estimates are important to describe the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) landscape and to guide public health decisions. The aims are to describe longitudinal changes in seroprevalence in children in a region in Northern Spain and to analyze factors associated with SARS-CoV-2 seropositivity. METHODS: Prospective multicenter longitudinal study with subjects recruited from July to September 2020. Children (up to 14 years old) were included and followed up until September 2021. Venous blood samples were collected every six months during three testing rounds and were analyzed for SARS-CoV-2 antibodies. The data regarding epidemiological features, contact tracing, symptoms, and virological tests were collected. The evolution of SARS-CoV-2 seroprevalence during the study and the differences between children with positive and negative SARS-CoV-2 antibody tests were analyzed. RESULTS: Two hundred children were recruited (50.5% girls, median age 9.7 years). The overall seroprevalence increased from round 1 [1.5%, 95% confidence interval (CI) 0.3%-4.3%] to round 2 (9.1%, 95% CI 4.6%-12.7%) and round 3 (16.6%, 95% CI 9.5%-19.6%) (P < 0.001). Main changes occurred in children aged zero to four years (P = 0.001) who lived in urban areas (P < 0.001). None of the children who were previously positive became seronegative. Following multivariable analysis, three variables independently associated with SARS-CoV-2 seropositivity were identified: close contact with coronavirus disease 2019 (COVID-19) confirmed or suspected cases [odds ratio (OR) = 3.9, 95% CI 1.2-12.5], previous positive virological test (OR = 17.1, 95% CI 3.7-78.3) and fatigue (OR = 18.1, 95% CI 1.7-193.4). CONCLUSIONS: SARS-CoV-2 seroprevalence in children has remarkably increased during the time of our study. Fatigue was the only COVID-19-compatible symptom that was more frequent in seropositive than in seronegative children.