Effects of select dietary supplements on the prevention and treatment of viral respiratory tract infections: a systematic review of randomized controlled trials

Efficacy and safety of a synbiotic infant formula for the prevention of respiratory and gastrointestinal infections: a randomized controlled trial

BACKGROUND

Early life nutrition is crucial for the development of the gut microbiota that, in turn, plays an essential role in the maturation of the immune system and the prevention of infections.

OBJECTIVES

The aim of this study was to investigate whether feeding synbiotic infants and follow-on formulas during the first year of life reduces the incidence rate (IR) of infectious diarrhea compared with standard formulas. Secondary endpoints included the IR of other infectious diseases as well as fecal milieu parameters.

METHODS

In this double-blind, controlled trial, 460 healthy, 1-mo-old infants were randomly assigned to receive a synbiotic [galacto-oligosaccharides (GOS)/Limosilactobacillus fermentum CECT 5716] (IF, n = 230) or a control formula (CF, n = 230) until 12 mo of age. A reference group of breastfed infants (HM, n = 80) was included. Data on infections were recorded throughout the study period and stool samples were collected at 4 and 12 mo of age.

RESULTS

IR of infectious diarrhea during the first year of life was 0.60 (CF), 0.56 (IF), and 0.29 (HM), with no statistically significant difference between groups. The IR of lower respiratory tract infections, 1 of the secondary endpoints, however, was lower in IF than in CF [0.79 compared with 1.01, IR ratio = 0.77 (0.60-1.00)]. Additionally, fecal pH was significantly lower at 4 mo (P < 0.0001), whereas secretory IgA was significantly higher at 12 mo of age (P = 0.015) in IF compared with CF.

CONCLUSIONS

Although no difference is observed in the incidence of diarrhea, consumption of a synbiotic formula containing L. fermentum CECT5716 and GOS in infancy may reduce the incidence of lower respiratory tract infections and affect the immune system and fecal milieu. Additional research is warranted to further investigate the potential interaction of the gut-lung axis. This trial was registered at clinicaltrials.gov as NCT02221687.

Systematical analyses of large-scale transcriptome reveal viral infection-related genes and disease comorbidities

Perturbation of transcriptome in viral infection patients is a recurrent theme impacting symptoms and mortality, yet a detailed understanding of pertinent transcriptome and identification of robust biomarkers is not complete. In this study, we manually collected 23 datasets related to 6,197 blood transcriptomes across 16 types of respiratory virus infections. We applied a comprehensive systems biology approach starting with whole-blood transcriptomes combined with multilevel bioinformatics analyses to characterize the expression, functional pathways, and protein-protein interaction (PPI) networks to identify robust biomarkers and disease comorbidities. Robust gene markers of infection with different viruses were identified, which can accurately classify the normal and infected patients in train and validation cohorts. The biological processes (BP) of different viruses showed great similarity and enriched in infection and immune response pathways. Network-based analyses revealed that a variety of viral infections were associated with nervous system diseases, neoplasms and metabolic diseases, and significantly correlated with brain tissues. In summary, our manually collected transcriptomes and comprehensive analyses reveal key molecular markers and disease comorbidities in the process of viral infection, which could provide a valuable theoretical basis for the prevention of subsequent public health events for respiratory virus infections.

Therapeutic Vitamin D Supplementation Following COVID-19 Diagnosis: Where Do We Stand?—A Systematic Review

Vitamin D has known immunomodulatory activity and multiple indications exist supporting its potential use against SARS-CoV-2 infection in the setting of the current pandemic. The purpose of this systematic review is to examine the efficacy of vitamin D administered to adult patients following COVID-19 diagnosis in terms of length of hospital stay, intubation, ICU admission and mortality rates. Therefore, PubMed and Scopus databases were searched for original articles referring to the aforementioned parameters. Of the 1376 identified studies, eleven were finally included. Vitamin D supplements, and especially calcifediol, were shown to be useful in significantly reducing ICU admissions and/or mortality in four of the studies, but not in diminishing the duration of hospitalization of COVID-19 patients. Due to the large variation in vitamin D supplementation schemes no absolute conclusions can be drawn until larger randomized controlled trials are completed. However, calcifediol administered to COVID-19 patients upon diagnosis represents by far the most promising agent and should be the focus of upcoming research efforts.

Risk Factors for the Mortality in Hospitalized Patients with COVID-19: A Brief Report

The cumulative rate of death of acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has necessitated better recognizing the risk factors of the disease and the COVID-19-induced mortality. This cross-sectional study aimed to determine the potential risk factors that predict COVID-19-related mortality concentrating on the initial recorded laboratory tests. We extracted admission's medical records of a total of 136 deaths related to COVID-19 and 272 discharged adult inpatients (≥18 years old) related to four referral centers from February 24th to April 12th, 2020, in Isfahan, Iran, to figure out the relationship between the laboratory findings and mortality beyond demographic and clinical findings. We applied the independent sample t test and a chichi square test with SPSS software to compare the differences between the survivor and non-survivor patients. A P value of less than 0.05 was considered significant. Our results showed that greater length of hospitalization (P≤0.001), pre-existing chronic obstructive pulmonary disease (P≤0.001), high pulse rate, hypoxia (P≤0.001), and high computed tomography scan score (P<0.001), in addition to high values of some laboratory parameters, increase the risk of mortality. Moreover, high neutrophil/lymphocyte ratio (OR, 1.890; 95% CI, 1.074-3.325, P=0.027), increased creatinine levels (OR, 15.488; 95% CI, 0.801-299.479, P=0.07), and elevated potassium levels (OR, 13.400; 95% CI, 1.084-165.618, P=0.043) independently predicted in-hospital death related to COVID-19 infection. These results emphasized the potential role of impaired laboratory parameters for the prognosis of fatal outcomes in adult inpatients.