• No evidence of a relationship between COVID-19 cases and temperature was found. • Results should not be extrapolated to other temperature ranges. • These results should be interpreted carefully due to data uncertainty and confounders. • It is important to account for nonmeteorological, spatial and temporal effects.

The new SARS-CoV-2 coronavirus has spread rapidly around the world since it was first reported in humans in Wuhan, China, in December 2019 after being contracted from a zoonotic source. This new virus produces the so-called coronavirus 2019 or COVID-19. Although several studies have supported the epidemiological hypothesis that weather patterns may affect the survival and spread of droplet-mediated viral diseases, the most recent have concluded that summer weather may offer partial or no relief of the COVID-19 pandemic to some regions of the world. Some of these studies have considered only meteorological variables, while others have included non-meteorological factors. The statistical and modelling techniques considered in this research line have included correlation analyses, generalized linear models, generalized additive models, differential equations, or spatio-temporal models, among others. In this paper we provide a systematic review of the recent literature on the effects of climate on COVID-19’s global expansion. The review focuses on both the findings and the statistical and modelling techniques used. The disparate findings reported seem to indicate that the estimated impact of hot weather on the transmission risk is not large enough to control the pandemic, although the wide range of statistical and modelling approaches considered may have partly contributed to the inconsistency of the findings. In this regard, we highlight the importance of being aware of the limitations of the different mathematical approaches, the influence of choosing geographical units and the need to analyse COVID-19 data with great caution. The review seems to indicate that governments should remain vigilant and maintain the restrictions in force against the pandemic rather than assume that warm weather and ultraviolet exposure will naturally reduce COVID-19 transmission.

Highlights Variations in air quality in terms of CO, SO 2 , PM 10 , O 3 and NO 2 levels were studied. The lockdown of Spain was not able to reduce severe air pollution in all its forms. Significant reductions of NO 2 levels were achieved in most cities. Increases of O3 pollution levels were found in several cities.

BackgroundThe SCORTEN score is a specific predictor of mortality for patients with Stevens–Johnson syndrome (SJS)/toxic epidermal necrolysis (TEN). There is little evidence in support of the common immunomodulating therapies for SJS/TEN.ObjectivesTo systematically assess the effectiveness of several therapies for SJS/TEN through the SCORTEN score.MethodsDatabases were searched for original studies on the use of SCORTEN. Six meta‐analyses were carried out on patients with SJS/TEN who received supportive care only or in combination with immunomodulating drugs: corticosteroids, cyclosporine, etanercept, immunoglobulins or a combination of corticosteroids with immunoglobulins. A multivariate meta‐regression and a network meta‐analysis were also performed.ResultsOf 3893 studies identified, fifty‐two involving 2466 patients with SJS/TEN were preselected. Data from thirty‐eight of these studies (1827 patients) were finally pooled, and results [log(SMR)] from meta‐analyses were as follows: −0.13 (95% CI, −0.42,0.16) for corticosteroids, −0.39 (95% CI, −0.87,0.09) for immunoglobulins, 0.13 (95% CI, −0.15,0.40) for supportive treatment, −0.88 (95% CI, −1.47, −0.29) for cyclosporine, −0.95 (95% CI, −1.82, −0.07) for etanercept and − 0.56 (95% CI, −0.94, −0.19) for immunoglobulins plus corticosteroids. The meta‐regression analysis confirmed that cyclosporine and immunoglobulins plus corticosteroids were associated with less deaths than predicted by SCORTEN. In the network meta‐analysis, no treatment achieved a significant reduction in the SMR.LimitationsHeterogeneity and quality of the included studies.ConclusionsSome treatments for SJS/TEN show a better performance, but there is not sufficient evidence to recommend its widespread use in all patients.

The use of probiotic starters remaining viable in unpasteurized and unfiltered beers could significantly increase health benefits. Here, the probiotic Saccharomyces cerevisiae var. boulardii (Sc b ) and a commercial Saccharomyces cerevisiae (Sc) strain, which is commonly employed in the brewing industry, are compared as single starters. The healthy value of the produced beers and growth performance in a laboratory bioreactor are analysed by determining antioxidant activity, phenolic content and profile, alcohol, biomass growth modelling by the logistic and Gompertz equations, biovolume estimation from 2D microscopy images, and yeast viability after fermentation. Thus, in this study, the craft beer produced with the probiotic yeast possessed higher antioxidant activity, lower alcohol content, similar sensory attributes, much higher yeast viability and more acidification, which is very desirable to reduce contamination risks at large-scale production. Furthermore, Sc b exhibited faster growth in the bioreactor culture and larger cell volumes than Sc, which increases the probiotic volume of the final craft beer. associated diarrhea [10,11] and may help to eradicate Helicobacter pylori [12]. In fact, the Sc b yeast is now commercially available in most countries globally.Sc b shows enhanced ability for pseudohyphal switching upon nitrogen limitation and increased resistance to acidic pH, which are not correlated with increased adherence to epithelial cells or transit through mouse gut [13]. However, a recent genetic comparative study of 5 Sc b against 145 Sc yeast strains has revealed the presence of two genes, HXT11 and HXT9, in Sc, which are not present in Sc b [14]. The absence of these genes has been related to greater resistance against several antifungals, such as cycloheximide, sulfometuron methyl and 4-nitroquinoline-N-oxide [15]. Other genetic particularities that have been reported for Sc b include the absence of ASP3 genes involved in asparagine degradation [16] and the abundant repetition of Flocculatıon (FLO) genes, which could explain the ability of Sc b to adhere to the intestinal epithelium [17,18].The optimal growth temperature of Sc b is 37 • C and thus it can reach very high gastrointestinal tract (GT) concentrations in a very short period [19]. In addition, it possesses the capacity to inhibit the growth, adherence and invasion of multiple pathogens such C. difficile [20], E. coli [21], and Candida albicans [22], both in in vitro and in vivo conditions to the epithelial layer of the GT.In recent years, there has been a worldwide increase in the consumer interest in craft beers, which are unpasteurized, unfiltered and without additional nitrogen or carbon dioxide pressure [23]. Even though there are many controversial studies about the beneficial effects of beer consumption on human health, epidemiological studies have shown that beer has positive effects on cardiovascular protection inhibiting atherosclerosis, decreasing the content of serum low-density lipoprotein cholesterol and triglycerides, b...