Laura Sánchez-De Prada

Background/Objectives: Asthma-coded hospital admissions in very young children represent a clinically relevant but diagnostically complex marker of severe wheezing/asthma-like morbidity. Methods: We conducted a nationwide ecological municipality-year study of children aged 0–3 years in Spain during 2020–2022 using hospital discharge records from the Spanish Minimum Basic Data Set (MBDS/RAE-CMBD). Exposure and outcome were analyzed at the municipality-year level: the exposure metric was the contemporaneous annual mean municipality-level concentration of PM_2.5, PM₁₀, NO₂, SO₂, O₃, and CO, and the outcome was the annual number of asthma-coded admissions, with the population aged 0–3 years as offset. Results: The regression panel comprised 20,746 municipality-year observations, 7251 municipalities, and 3231 admissions; 93.7% of municipality-years had zero admissions. In unipollutant Poisson models adjusted for calendar year, rural–urban status, temperature, and relative humidity, incidence rate ratios per interquartile-range increase were 1.54 (95% CI 1.28–1.85) for PM_2.5 and 1.89 (95% CI 1.59–2.26) for PM₁₀. Negative-binomial and province-fixed-effect sensitivity models attenuated but did not remove the particulate-matter signal. The multipollutant model was unstable because of strong collinearity between particulate fractions and was interpreted only as an exploratory sensitivity analysis. Conclusions: These findings should be interpreted as ecological, population-level associations between annual ambient particulate pollution and pediatric respiratory hospital burden, not as individual-level causal risk estimates.

Introduction: Pregnant women are considered a vulnerable group for COVID-19 with an increased risk for complications. The objective of this study is to describe in-hospital mortality, pregnancy outcomes, and direct hospital costs associated with COVID-19 in women at the time of childbirth.Methods: This retrospective nationwide population-based registry study collects data on complications, outcomes, and direct hospital costs from women hospitalized for childbirth, recorded in the Minimum Basic Data Set obtained from the National Surveillance System for Hospital Data in Spain between 2020–2022. Hospitalization characteristics, complications related to pregnancy and childbirth, outcomes, and hospitalization costs are compared between COVID-19-positive and non-COVID-19 women at the time of childbirth.Results: A total of 779,387 women were admitted between 2020 and 2022 with a record of childbirth in Spanish hospitals. Of these, 15,792 (2.06%) had COVID-19 at the time of delivery. These women had a longer length of stay (3.53 days), higher rates of intensive care unit (ICU) admission (2.53%), ventilation/intubation (0.91%), and in-hospital mortality (0.06%) (p < 0.0001). This group also exhibited higher rates of spontaneous premature onset of labor (7%) and postpartum hemorrhage (3.45%), as well as a higher rate of labor induction (6.27%) (p < 0.001). Additionally, a higher single stillbirth rate (0.73%) was found among COVID-19-positive women (p = 0.0002). A significant higher risk of postpartum hemorrhage (OR = 1.14), embolism (OR = 7.98), acute respiratory distress syndrome (OR = 35.5), temporary tracheostomy (OR = 4.89), ventilation/intubation (OR = 6.85), and single stillbirth (OR = 1.32) was found in COVID-19 women (p < 0.05). The mean cost per patient was €4,066.48, 25.06% higher than that for non-COVID-19 women (p < 0.0001). Stratification by age showed an increasing trend in costs with age, reaching €6,492.12 in women ≥45 years old, where the ICU admission rate reached 8.09%.Conclusion: These findings show that COVID-19 at the time of childbirth occurs in 2 out of every 100 cases and increases the risk of complications related to pregnancy and childbirth, as well as mortality and hospitalization costs. These data are related to SARS-CoV-2 variants circulating from 2020–2022, and current variants could give different risks. Our evaluation should be useful for health authorities to allocate resources and professionals to implement preventive measures, such as vaccination and screening, due to the increased morbidity, mortality and costs in this group.

The properties of the main surface proteins and the viral cycle of the respiratory syncytial virus (RSV) make it an attractive pathogen from the perspective of microbiology. The virus gets its name from the manner it infects cells, which enables it to produce syncytia, which allow the virus’ genetic material to move across cells without having to release viral offspring to the cellular exterior, reducing immune system identification. This causes a disease with a high impact in both children and adults over 60, which has sparked the development of several preventive interventions based on vaccines and monoclonal antibodies for both age groups. The epidemiological characteristics of this virus, which circulates in epidemics throughout the coldest months of the year and exhibits a marked genetic and antigenic drift due to its high mutation capability, must be taken into consideration while using these preventive methods. The most important microbiological and epidemiological elements of RSV are covered in this study, along with how they have affected the creation of preventive medications and their use in the future.

SARS-CoV-2 reinfections have been frequent, even among those vaccinated. The aim of this study is to know if hybrid immunity (infection + vaccination) is affected by the moment of vaccination and number of doses received. We conducted a retrospective study in 746 patients with a history of COVID-19 reinfection and recovered the dates of infection and reinfection and vaccination status (date and number of doses). To assess differences in the time to reinfection(t_RI) between unvaccinated, vaccinated before 6 months, and later; and comparing one, two or three doses (incomplete, complete and booster regime) we performed the log-rank test of the cumulative incidence calculated as 1 minus the Kaplan–Meier estimator. Also, an adjusted Cox-regression was performed to evaluate the risk of reinfection in all groups. The t_RI was significantly higher in those vaccinated vs. non-vaccinated (p < 0.001). However, an early incomplete regime protects similar time than not receiving a vaccine. Vaccination before 6 months after infection showed a lower t_RI compared to those vaccinated later with the same regime (adj-p < 0.001). Actually, early vaccination with complete and booster regimes provided lower length of protection compared to vaccinating later with incomplete and complete regime, respectively. Vaccination with complete and booster regimes significantly increases the t_RI (adj-p < 0.001). Vaccination increases the time it takes for a person to become reinfected with SARS-CoV-2. Increasing the time from infection to vaccination increases the time in which a person could be reinfected and reduces the risk of reinfection, especially in complete and booster regimes. Those results emphasize the role of vaccines and boosters during the pandemic and can guide strategies on future vaccination policy.

Introduction: COVID-19 transmission has been characterized by the presence of asymptomatic patients. Additionally, most studies evaluating costs focus on symptomatic COVID-19 cases.Objective: To describe the prevalence, characteristics, and costs of asymptomatic COVID-19 cases at admission in Spanish hospitals in 2020.Methods: A nationwide study was performed, and data of hospitalized patients were collected of the Minimum Basic Data Set in Spain during 2020. Patients with COVID-19 codes as a primary and as a secondary diagnosis at admission were selected. Variables collected included age, sex, length of stay, in-hospital death, admission, length of stay and death in intensive care unit, mechanical ventilation and ventilatory assistance. COVID-19 related hospital costs were calculated using diagnosis-related groups from the Minimum Basic Data Set. Patients and costs were disaggregated by sex, age group, intensive care unit admission and epidemic wave (first or second) and main diagnosis.Results: A total of 14,742 patients were admitted with asymptomatic COVID-19 in Spanish hospitals representing 6.35% of all COVID-19 admitted patients. The total cost of admissions with asymptomatic COVID-19 was €105,933,677.6 with a mean cost per patient of €7,185.8 with higher mean cost in the first wave despite only 2.7% of cases were found during that time. Based on primary diagnosis, the higher number of cases of asymptomatic COVID-19 were found in “Pregnancy, childbirth and the puerperium” followed by “diseases of the circulatory system”.Conclusions: There was a high prevalence of asymptomatic cases during screening at admission process in Spanish hospitals in 2020. The highest number of cases was found among the group of “pregnancy, childbirth, and puerperium” followed by “diseases of the circulatory system.” The higher costs might be due not only to the main pathology at admission but to the associated healthcare provisions needed in case of positive COVID-19 testing.

Purpose: SARS-CoV-2 reinfections have been frequent, even among those vaccinated. The aim of this study is to know if hybrid immunity (infection+vaccination) is affected by the moment of vaccination and the number of doses received. Methods: We conducted a retrospective study in 745 patients with a history of COVID-19 reinfection and recovered the dates of infection and reinfection and vaccination status (date and number of doses). To assess differences in the time to reinfection(t_RI) between unvaccinated, vaccinated before 6 months and later, and comparing one, two or three doses(incomplete, complete and booster regime) we performed the log-rank test of the cumulative incidence calculated as 1 minus the Kaplan-Meier estimator. Results: The t_RI was significantly higher in those vaccinated vs. non-vaccinated (qRI compared to those vaccinated later with the same regime(qRI(qConclusion: Vaccination increases the time it takes for a person to become reinfected with SARS-CoV-2. Increasing the time from infection to vaccination increases the time in which a person could be reinfected. Booster doses increase the time to reinfection. Those results emphasize the role of vaccines and boosters during the pandemic and can guide strategies on future vaccination policy.