Browsing by Issue Date, starting with "2023-03-08"
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- Short-Term Association between Sulfur Dioxide and Mortality: A Multicountry Analysis in 399 CitiesPublication . O’Brien, Edward; Masselot, Pierre; Sera, Francesco; Roye, Dominic; Breitner, Susanne; Ng, Chris Fook Sheng; de Sousa Zanotti Stagliorio Coelho, Micheline; Madureira, Joana; Tobias, Aurelio; Vicedo-Cabrera, Ana Maria; Bell, Michelle L.; Lavigne, Eric; Kan, Haidong; Gasparrini, Antonio; MCC Collaborative Research NetworkBackground: Epidemiological evidence on the health risks of sulfur dioxide (sulfur dioxide SO2) is more limited compared with other pollutants, and doubts remain on several aspects, such as the form of the exposure–response relationship, the potential role of copollutants, as well as the actual risk at low concentrations and possible temporal variation in risks. Objectives: Our aim was to assess the short-term association between exposure to sulfur dioxide SO2 and daily mortality in a large multilocation data set, using advanced study designs and statistical techniques. Methods: The analysis included 43,729,018 deaths that occurred in 399 cities within 23 countries between 1980 and 2018. A two-stage design was applied to assess the association between the daily concentration of sulfur dioxide SO2 and mortality counts, including first-stage time-series regressions and second-stage multilevel random-effect meta-analyses. Secondary analyses assessed the exposure–response shape and the lag structure using spline terms and distributed lag models, respectively, and temporal variations in risk using a longitudinal meta-regression. Bi-pollutant models were applied to examine confounding effects of particulate matter with an aerodynamic diameter of less than or equal to 10 micrometers≤10μm (particulate matter begin subscript 10 end subscriptPM10) and 2.5 micrometers2.5μm (particulate matter begin subscript 2.5 end subscriptPM2.5), ozone, nitrogen dioxide, and carbon monoxide. Associations were reported as relative risks (RRs) and fractions of excess deaths. Results: The average daily concentration of sulfur dioxideSO2 across the 399 cities was 11.7 micrograms per meter cubed11.7 μg/m3, with 4.7% of days above the World Health Organization (WHO) guideline limit (40 micrograms per meter cubed40 μg/m3, 24-h average), although the exceedances occurred predominantly in specific locations. Exposure levels decreased considerably during the study period, from an average concentration of 19.0 micrograms per meter cubed19.0 μg/m3 in 1980–1989 to 6.3 micrograms per meter cubed6.3 μg/m3 in 2010–2018. For all locations combined, a 10 microgram per meter cubed10-μg/m3 increase in daily sulfur dioxide SO2 was associated with an RR of mortality of 1.0045 [95% confidence interval (CI): 1.0019, 1.0070], with the risk being stable over time but with substantial between-country heterogeneity. Short-term exposure to sulfur dioxide SO2 was associated with an excess mortality fraction of 0.50% [95% empirical CI (eCI): 0.42%, 0.57%] in the 399 cities, although decreasing from 0.74% (0.61%, 0.85%) in 1980–1989 to 0.37% (0.27%, 0.47%) in 2010–2018. There was some evidence of nonlinearity, with a steep exposure–response relationship at low concentrations and the risk attenuating at higher levels. The relevant lag window was 0–3 d. Significant positive associations remained after controlling for other pollutants. Discussion: The analysis revealed independent mortality risks associated with short-term exposure to sulfur dioxideSO2, with no evidence of a threshold. Levels below the current WHO guidelines for 24-h averages were still associated with substantial excess mortality, indicating the potential benefits of stricter air quality standards.
- First comparative genomic characterization of the MSSA ST398 lineage detected in aquaculture and other reservoirsPublication . Salgueiro, Vanessa; Manageiro, Vera; Bandarra, Narcisa M.; Ferreira, Eugénia; Clemente, Lurdes; Caniça, ManuelaStaphylococcus aureus ST398 can cause diseases in several different animals. In this study we analyzed ten S. aureus ST398 previously collected in three different reservoirs in Portugal (humans, gilthead seabream from aquaculture and dolphin from a zoo). Strains tested against sixteen antibiotics, by disk diffusion or minimum inhibitory concentration, showed decreased susceptibility to benzylpenicillin (all strains from gilthead seabream and dolphin) and to erythromycin with an iMLSB phenotype (nine strains), and susceptibility to cefoxitin (methicillin-susceptible S. aureus, MSSA). All strains from aquaculture belonged to the same spa type, t2383, whereas strains from the dolphin and humans belonged to spa type t571. A more detailed analysis using single nucleotide polymorphisms (SNPs)-based tree and a heat map, showed that all strains from aquaculture origin were highly related with each other and the strains from dolphin and humans were more distinct, although they were very similar in ARG, VF and MGE content. Mutations F3I and A100V in glpT gene and D278E and E291D in murA gene were identified in nine fosfomycin susceptible strains. The blaZ gene was also detected in six of the seven animal strains. The study of the genetic environment of erm(T)-type (found in nine S. aureus strains) allowed the identification of MGE (rep13-type plasmids and IS431R-type), presumably involved in the mobilization of this gene. All strains showed genes encoding efflux pumps from major facilitator superfamily (e.g., arlR, lmrS-type and norA/B-type), ATP-binding cassettes (ABC; mgrA) and multidrug and toxic compound extrusion (MATE; mepA/R-type) families, all associated to decreased susceptibility to antibiotics/disinfectants. Moreover, genes related with tolerance to heavy metals (cadD), and several VF (e.g., scn, aur, hlgA/B/C and hlb) were also identified. Insertion sequences, prophages, and plasmids made up the mobilome, some of them associated with ARG, VF and genes related with tolerance to heavy metals. This study highlights that S. aureus ST398 can be a reservoir of several ARG, heavy metals resistance genes and VF, which are essential in the adaption and survival of the bacterium in the different environments and an active agent in its dissemination. It makes an important contribution to understanding the extent of the spread of antimicrobial resistance, as well as the virulome, mobilome and resistome of this dangerous lineage.