BACKGROUND: Human adenovirus (HAdV) is an important pathogen causing acute respiratory infection (ARI) in children. Many countries, including China, have experienced sporadic or outbreaks related to HAdV-4, and death cases were reported. However, there is little research on HAdV-4 and the epidemic situation of HAdV-4 in China is little known. This study was designed to comprehend the prevalence and genetic characteristics of HAdV-4 in ARI children in China.
METHODS: Respiratory tract samples from ARI children hospitalized in six hospitals of Northern and Southern China from 2017 to 2020 were collected for HAdV detection and typing. Clinical information was collected from HAdV-4 positive patients for clinical characteristics and epidemiological analysis. The main capsid proteins and the whole genome sequences were amplified and sequenced for bioinformatics analysis.
RESULTS: There were 2847 ARI children enrolled, and 156 (5.48%) HAdV positive samples were detected. Eleven HAdV-4 positive samples were identified, accounting for 0.39% of the total samples and 7.05% of the HAdV positive samples. The main manifestations were fever and cough. Two children had conjunctivitis. Two children were diagnosed with severe pneumonia and developed respiratory failure. One of them developed hemophagocytic syndrome and checked in pediatric intensive care unit (PICU). This child had ventricular septal defect. All the children recovered. The isolated strains of HAdV-4 obtained in this study and the reference strains from China located in the same phylogenetic branch (HAdV-4a), while the prototype strain and vaccine strains formed another branch (HAdV-4p). Upon comparison with the prototype strain, there were a few amino acid mutations existing in three major capsid proteins. According to recombination analysis, no new recombination was found.
CONCLUSIONS: The detection rate of HAdV-4 in children hospitalized with ARI was 0.39% in the total samples and 7.05% of all HAdV positive samples. HAdV-4 isolates obtained in this study and other reference strains from China belonged to the HAdV-4a subtype. Our data provided reference for the monitoring, prevention and control of HAdV-4, as well as the research and development of vaccines and drugs.

OBJECTIVE: To evaluate the effectiveness of weekly vitamin D supplementation in reducing the number of acute respiratory infections (ARI) in preschool children.
METHODS: Randomized, double-blind, placebo-controlled trial in 303 children aged 1.5-3.5 years from 2014 to 2105 in three Chilean cities at different latitudes: Santiago (33ºS, n=101), Talcahuano (37ºS, n=103), and Punta Arenas (53ºS, n=99). Participants were allocated (1:1:1) to receive placebo, cholecalciferol (VD3) 5,600 IU/week (low-dose), or 11,200 IU/week (high-dose) for 6 months. Primary outcome was parent-reported number of ARI; secondary outcomes included number of ARI hospitalizations, change of serum 25(OH)D and LL37/cathelicidin levels, and adverse events.
RESULTS: The mean age of participants was 26 ± 6 months; 45% were female. Baseline 25(OH)D was 24.9 ± 6.1 ng/ml, with 23% having 25(OH)D <20 ng/ml. No significant baseline clinical or laboratory differences were observed among groups. Overall, 64% (n=194) completed study participation, without baseline differences between subjects lost to follow-up versus those completing participation or differences in completion rates across groups. After 6 months, a dose-dependent increase in serum 25(OH)D was observed from the VD3 intervention (p<0.001), with a higher proportion of subjects ending the trial with 25(OH)D <20 ng/ml in the placebo group (30.8%) versus the low-dose (7.4%) and high-dose groups (5.1%). However, no group differences were observed in number of ARI (p=0.85), ARI hospitalizations (p=0.20), LL-37/cathelicidin change (p=0.30), or adverse events (p=0.41).
CONCLUSIONS: While weekly VD3 supplementation, in doses equivalent to 800 IU and 1600 IU daily, was associated with improved 25(OH)D levels in preschoolers, we did not find a reduced number of ARI in this sample.

UNASSIGNED: Acute respiratory infection is an infectious illness caused by acute viral or bacterial infection. According to a 2018 WHO report, exposures to indoor and ambient air environmental pollution were contributing factors to a higher risk of respiratory problems following 7 million deaths of children under five globally. Housing conditions such as wall material, roof type, kitchen location, sanitation condition, and cooking fuel type are household-level predictors of acute respiratory disease among children under five years of age.
UNASSIGNED: This research used EDHS-2016 secondary data, which are nationally representative. The data collection period was from January 18, 2016, to June 27, 2016. Among the 16,650 total surveys, 10,006 households that had children below 5 years of age. The outcome variable for this study was acute respiratory infection symptoms. Analyses were performed using STATA Version 17.1. The data were weighted before performing analysis to reinstate the representativeness of the sample. In the bivariable analysis, a p value <0.2 was used to screen for multivariable. Multicollinearity was checked using the variance inflation factor. Then, a multilevel multivariable regression model was used in this study for the analysis of acute respiratory infection symptoms and possible predictor variables. Variables with a p value <0.05 in multivariable regression analysis were considered statistically significant predictors.
UNASSIGNED: Most (95.00%) households commonly used solid fuel for cooking, and household main construction materials: 81.44 and 91.03% of floors and walls of households were constructed with unprocessed natural materials, respectively. The prevalence of acute respiratory infection symptoms among children under five years of age was 7.955% (7.397, 8.551%). The findings indicated that acute respiratory infection symptoms among children under five years of age were significantly linked with the age of the children, diarrhea status, residence, region, fuel type, stool disposal, wall material, and floor material.
UNASSIGNED: Interventions should target modifiable factors such as proper stool disposal of the youngest child, informing the health effects of poor housing conditions such as improving wall and floor construction material to reduce acute respiratory infection symptoms among children under five years of age.

BACKGROUND: Vitamin D supplementation may prevent acute respiratory infections (ARIs). This study aimed to identify the optimal methods of vitamin D supplementation.
METHODS: PubMed, Embase, Cochrane Central Register of Controlled Trials, Web of Science, and the ClinicalTrials.gov registry were searched from database inception through July 13, 2023. Randomized-controlled trials (RCTs) were included. Data were pooled using random-effects model. The primary outcome was the proportion of participants with one or more ARIs.
RESULTS: The analysis included 43 RCTs with 49320 participants. Forty RCTs were considered to be at low risk for bias. The main pairwise meta-analysis indicated there were no significant preventive effects of vitamin D supplementation against ARIs (risk ratio [RR]: 0.99, 95% confidence interval [CI]: 0.97 to 1.01, I2 = 49.6%). The subgroup dose-response meta-analysis indicated that the optimal vitamin D supplementation doses ranged between 400-1200 IU/day for both summer-sparing and winter-dominant subgroups. The subgroup pairwise meta-analysis also revealed significant preventive effects of vitamin D supplementation in subgroups of daily dosing (RR: 0.92, 95% CI: 0.85 to 0.99, I2 = 55.7%, number needed to treat [NNT]: 36), trials duration < 4 months (RR: 0.81, 95% CI: 0.67 to 0.97, I2 = 48.8%, NNT: 16), summer-sparing seasons (RR: 0.85, 95% CI: 0.74 to 0.98, I2 = 55.8%, NNT: 26), and winter-dominant seasons (RR: 0.79, 95% CI: 0.71 to 0.89, I2 = 9.7%, NNT: 10).
CONCLUSIONS: Vitamin D supplementation may slightly prevent ARIs when taken daily at doses between 400 and 1200 IU/d during spring, autumn, or winter, which should be further examined in future clinical trials.

UNASSIGNED: This study aimed to map the incidence of acute respiratory infections (ARIs) among under-5 children in Indonesia, address the triple burden of malnutrition, and analyze the impact of malnutrition on ARIs, taking into account the environmental and wealth disparities in Indonesia.
UNASSIGNED: This study utilized an ecological design, analyzing aggregate data from the Indonesia Nutrition Survey, 2022. It encompassed 33 provinces and 486 districts/cities, involving a total of 334,848 children under 5 years of age. Partial least squares structural equation modeling was employed to investigate the relationships among wealth, environment, malnutrition (stunting, wasting, and underweight), and ARIs.
UNASSIGNED: The proportion of ARI cases in Indonesia was generally concentrated in central Sumatra, the western and eastern parts of Java, and eastern Papua. In contrast, the northern part of Sumatra, central Kalimantan, central Sulawesi, and central Papua had a higher proportion of malnutrition cases compared to other regions. Negative associations were found between malnutrition and ARIs (path coefficient = -0.072, p<0.01) and between wealth and environment (path coefficient = -0.633, p<0.001), malnutrition (path coefficient = -0.399, p<0.001), and ARIs (path coefficient = -0.918, p<0.001).
UNASSIGNED: An increasing wealth index is expected to contribute to reducing ARIs, malnutrition and environmental burdens in the future. This study emphasizes the necessity for focused strategies that address both immediate health challenges and the underlying socioeconomic determinants to improve child health outcomes in the Indonesian context.

UNASSIGNED: Although the prevalence of childhood illnesses has significantly decreased, acute respiratory infections continue to be the leading cause of death and disease among children in low- and middle-income countries. Seven percent of children under five experienced symptoms in the two weeks preceding the Ethiopian demographic and health survey. Hence, this study aimed to identify interpretable predicting factors of acute respiratory infection disease among under-five children in Ethiopia using machine learning analysis techniques.
UNASSIGNED: Secondary data analysis was performed using 2016 Ethiopian demographic and health survey data. Data were extracted using STATA and imported into Jupyter Notebook for further analysis. The presence of acute respiratory infection in a child under the age of 5 was the outcome variable, categorized as yes and no. Five ensemble boosting machine learning algorithms such as adaptive boosting (AdaBoost), extreme gradient boosting (XGBoost), Gradient Boost, CatBoost, and light gradient-boosting machine (LightGBM) were employed on a total sample of 10,641 children under the age of 5. The Shapley additive explanations technique was used to identify the important features and effects of each feature driving the prediction.
UNASSIGNED: The XGBoost model achieved an accuracy of 79.3%, an F1 score of 78.4%, a recall of 78.3%, a precision of 81.7%, and a receiver operating curve area under the curve of 86.1% after model optimization. Child age (month), history of diarrhea, number of living children, duration of breastfeeding, and mother\'s occupation were the top predicting factors of acute respiratory infection among children under the age of 5 in Ethiopia.
UNASSIGNED: The XGBoost classifier was the best predictive model with improved performance, and predicting factors of acute respiratory infection were identified with the help of the Shapely additive explanation. The findings of this study can help policymakers and stakeholders understand the decision-making process for acute respiratory infection prevention among under-five children in Ethiopia.

Diagnosis of acute respiratory infections (ARIs) is challenging due to the broad diversity of potential microbial causes. We used metagenomic next-generation sequencing (mNGS) to analyze the nasopharyngeal virome of ARI patients, who had undergone testing with a clinical multiplex PCR panel (Amplisens ARVI-screen-FRT). We collected nasopharyngeal swabs from 49 outpatient adults, 32 of whom had ARI symptoms and were PCR-positive, and 4 asymptomatic controls in Kazakhstan during Spring 2021. We assessed the biodiversity of the mNGS-derived virome and concordance with PCR results. PCR identified common ARI viruses in 65% of the symptomatic cases. mNGS revealed viral taxa consisting of human, non-human eukaryotic and bacteriophage groups, comprising 15, 11 and 28 genera, respectively. Notable ARI-associated human viruses included rhinovirus (16.3%), betaherpesvirus 7 (14.3%) and Epstein-Barr virus (8.16%). The primary phage hosts were Streptococcus spp. (32.7%), Pseudomonas aeruginosa (24.5%) and Burkholderia spp. (20.4%). In total, 47% of ARIs were linked solely to bacterial pathogens, a third to viral-bacterial co-infections, and less than 10% to only viral infections by mNGS. PCR showed low concordance with mNGS, except for rhinovirus. These results underscore the importance of broad diagnostic methods and question the effectiveness of commonly used PCR panels in ARI diagnosis.

UNASSIGNED: The aims of this study were to examine the effect of SARS-CoV-2 infection on cardiorespiratory fitness (CRF) and time-trial performance in vaccinated well-trained young kayak athletes.
UNASSIGNED: This is a longitudinal observational study. Sixteen (7 male, 9 female) vaccinated kayakers underwent body composition assessment, maximal graded exercise test, and 1000-m time-trial tests 21.9 ± 1.7 days before and 66.0 ± 2.2 days after the SARS-CoV-2 infection. The perception of training load was quantified with Borg\'s CR-10 scale before and after the infection return to sport period.
UNASSIGNED: There were significant decreases in peak oxygen uptake (-9.7 %; effect size [ES] = 1.38), peak oxygen pulse (-5.7 %; ES = 0.96), and peak heart rate (-1.9 %; ES = 0.61). Peak minute ventilation, and minute ventilation/carbon dioxide production slope were unchanged after infection compared to the pre-infection values. In the entire 1000-m, the impaired tendencies were found in completion time, mean power, and mean speed (-2.4 to 1.2 %; small ESs = -0.40 to 0.47) as well as significant changes in stroke rate and stroke length (-4.5 to 3.7 %; ESs = -0.60 to 0.73).
UNASSIGNED: SARS-CoV-2 infection decreased CRF and time-trial performance even two months after return to regular training in vaccinated athletes.

Symptoms of Acute Respiratory infections (ARIs) among under-five children are a global health challenge. We aimed to train and evaluate ten machine learning (ML) classification approaches in predicting symptoms of ARIs reported by mothers among children younger than 5 years in sub-Saharan African (sSA) countries. We used the most recent (2012-2022) nationally representative Demographic and Health Surveys data of 33 sSA countries. The air pollution covariates such as global annual surface particulate matter (PM 2.5) and the nitrogen dioxide available in the form of raster images were obtained from the National Aeronautics and Space Administration (NASA). The MLA was used for predicting the symptoms of ARIs among under-five children. We randomly split the dataset into two, 80% was used to train the model, and the remaining 20% was used to test the trained model. Model performance was evaluated using sensitivity, specificity, accuracy, and the area under the receiver operating characteristic curve. A total of 327,507 under-five children were included in the study. About 7.10, 4.19, 20.61, and 21.02% of children reported symptoms of ARI, Severe ARI, cough, and fever in the 2 weeks preceding the survey years respectively. The prevalence of ARI was highest in Mozambique (15.3%), Uganda (15.05%), Togo (14.27%), and Namibia (13.65%,), whereas Uganda (40.10%), Burundi (38.18%), Zimbabwe (36.95%), and Namibia (31.2%) had the highest prevalence of cough. The results of the random forest plot revealed that spatial locations (longitude, latitude), particulate matter, land surface temperature, nitrogen dioxide, and the number of cattle in the houses are the most important features in predicting the diagnosis of symptoms of ARIs among under-five children in sSA. The RF algorithm was selected as the best ML model (AUC = 0.77, Accuracy = 0.72) to predict the symptoms of ARIs among children under five. The MLA performed well in predicting the symptoms of ARIs and associated predictors among under-five children across the sSA countries. Random forest MLA was identified as the best classifier to be employed for the prediction of the symptoms of ARI among under-five children.

UNASSIGNED: This study examines the seasonal and genetic characteristics of human metapneumovirus (HMPV) in Henan from 2017 to 2023.
UNASSIGNED: Samples from patients with acute respiratory infection (ARI) testing positive for HMPV were subjected to real-time reverse transcription polymerase chain reaction The G gene was amplified and sequenced from these samples for epidemiological and phylogenetic analysis.
UNASSIGNED: We enrolled 2,707 ARI patients from October 2017 to March 2023, finding an HMPV positivity rate of 6.17% (167/2,707). Children under five exhibited the highest infection rate at 7.78% (138/1,774). The 2018 and 2019 HMPV outbreaks predominantly occurred in spring (March to May), with peak positivity rates of 31.11% in May 2018 and 19.57% in May 2019. A notable increase occurred in November 2020, when positivity reached a historic high of 42.11%, continuing until January 2021. From February 2021 through March 2023, no significant seasonal peaks were observed, with rates ranging from 0% to 8.70%. Out of 81 G gene sequences analyzed, 46.91% (38/81) were identified as subtype A (A2c: 45.67%, 37/81; A2b: 1.23%, 1/81) and 53.09% (43/81) as subtype B (B1: 9.88%, 8/81; B2: 43.21%, 35/81). Notably, an AAABBA switch pattern was observed in HMPV subtypes. The dominant strains were A2c111nt-dup in subtype A and B2 in subtype B.
UNASSIGNED: Six years of surveillance in Henan Province has detailed the seasonal and genetic dynamics of HMPV, contributing valuable insights for the control and prevention of HMPV infections in China. These findings support the development of targeted HMPV vaccines and immunization strategies.