Search Results (4)

Background: Ambient air pollution remains a major risk factor for population health worldwide. The impact of PM_2.5 air pollution is underestimated in sub-Saharan Africa due to a lack of epidemiological studies. AirQ+ is proposed to reduce these inequalities in research. The aim of this study is to assess, by AirQ+, the impact of prolonged exposure to PM_2.5 on respiratory health in Kinshasa in 2019, and to estimate the health benefits of reducing this air pollution. Methods: Population and mortality data were obtained from the Institut National de la Statistique and the Institut de Métrologie et d’Évaluation en santé, respectively. PM_2.5 concentrations were measured using PurpleAir PA-II-SD sensors, and average annual concentration was 43.5 µg/m³ in 2019. AirQ+ was used to estimate the health effect attributable to PM_2.5 in adults aged over 25 in Kinshasa. Results: In 2019, the proportion of deaths attributable to PM_2.5 air pollution was 30.72% for ALRI, 26.55% for COPD and 24.32% for lung cancers. Each 10% reduction in current PM_2.5 levels would prevent 1093 deaths (from all causes) per year in Kinshasa. Life expectancy would increase by 4.7 years (CI 3.5–5.3) if the WHO threshold of 5 mg/m³ were respected. Conclusions: The results of this study highlight the major respiratory public health problem associated with air pollution by fine particles in Kinshasa. AirQ+ was used to assess the impact of prolonged exposure to PM_2.5 and respiratory deaths among adults in Kinshasa and revealed that this number of deaths could be avoided by improving air quality. Full article

Worldwide, human respiratory syncytial virus (RSV) is the most common etiological agent for acute lower respiratory tract infections (ALRI). RSV-ALRI is the major cause of hospital admissions in young children, and it can cause in-hospital deaths in children younger than six months old. Therefore, RSV remains one of the pathogens deemed most important for the generation of a vaccine. On the other hand, the effectiveness of a vaccine depends on the development of immunological memory against the pathogenic agent of interest. This memory is achieved by long-lived memory T cells, based on the establishment of an effective immune response to viral infections when subsequent exposures to the pathogen take place. Memory T cells can be classified into three subsets according to their expression of lymphoid homing receptors: central memory cells (T_CM), effector memory cells (T_EM) and resident memory T cells (T_RM). The latter subset consists of cells that are permanently found in non-lymphoid tissues and are capable of recognizing antigens and mounting an effective immune response at those sites. T_RM cells activate both innate and adaptive immune responses, thus establishing a robust and rapid response characterized by the production of large amounts of effector molecules. T_RM cells can also recognize antigenically unrelated pathogens and trigger an innate-like alarm with the recruitment of other immune cells. It is noteworthy that this rapid and effective immune response induced by T_RM cells make these cells an interesting aim in the design of vaccination strategies in order to establish T_RM cell populations to prevent respiratory infectious diseases. Here, we discuss the biogenesis of T_RM cells, their contribution to the resolution of respiratory viral infections and the induction of T_RM cells, which should be considered for the rational design of new vaccines against RSV. Full article

Acute Lower Respiratory Tract Infections (ALRI) are one of the most common causes of morbidity and mortality in young children. Zinc supplementation has been shown to have a preventive effect against respiratory infections, but little evidence is available on its effect on the treatment of ALRI. This study examined the effect of zinc supplementation on the treatment outcome in children that were hospitalized with ALRI. A randomized, doubleblinded, placebo-controlled trial was conducted on 64 hospitalized children with ALRI, who were aged between 2 and 60 months. Children were randomly allocated to receive zinc (30 mg elemental zinc/day) or placebo. The primary outcome was the time to the cessation of ALRI, while the secondary outcomes were the length of the stay in hospital and the individual features of the disease. The study found that ALRI cessation was faster in children who received zinc supplementation (median (IQR): 3 (2-4) days and 4 (3-5) days, respectively; P=0.008), and that their hospital stay was shorter (mean (SD): 3.8 (1.3) days and 6.1 (3.2) days, respectively; P<0.001) than the placebo group. Zinc supplementation was well-tolerated, and no adverse events were reported. In conclusion, zinc supplementation reduced the number of days of ALRI in Thai children, as well as their stay in hospital. Full article

There is an ongoing global pandemic of human respiratory syncytial virus (RSV) infection that results in substantial annual morbidity and mortality. In Australia, RSV is a major cause of acute lower respiratory tract infections (ALRI). Nevertheless, little is known about the extent and origins of the genetic diversity of RSV in Australia, nor the factors that shape this diversity. We have conducted a genome-scale analysis of RSV infections in New South Wales (NSW). RSV genomes were successfully sequenced for 144 specimens collected between 2010–2016. Of these, 64 belonged to the RSVA and 80 to the RSVB subtype. Phylogenetic analysis revealed a wide diversity of RSV lineages within NSW and that both subtypes evolved rapidly in a strongly clock-like manner, with mean rates of approximately 6–8 × 10⁻⁴ nucleotide substitutions per site per year. There was only weak evidence for geographic clustering of sequences, indicative of fluid patterns of transmission within the infected population and no evidence of any clustering by patient age such that viruses in the same lineages circulate through the entire host population. Importantly, we show that both subtypes circulated concurrently in NSW with multiple introductions into the Australian population in each year and only limited evidence for multi-year persistence. Full article