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Bacillus thuringiensis serovar israelensis (Bti) is used to control insect vectors of human and animal diseases. In the present study, the toxicity of four strains of Bti, named T0124, T0131, T0137, and T0139, toward Aedes aegypti and Culex quinquefasciatus larvae was analyzed. The T0131 strain showed the highest larvicidal activity against A. aegypti (LC50 = 0.015 µg/ml) and C. quinquefasciatus larvae (LC50 = 0.035 µg/ml) when compared to the other strains. Furthermore, the genomic sequences of the four strains were obtained and compared. These Bti strains had chromosomes sizes of approximately 5.4 Mb with GC contents of ~35% and 5472–5477 putative coding regions. Three small plasmids (5.4, 6.8, and 7.6 kb) and three large plasmids (127, 235, and 359 kb) were found in the extrachromosomal content of all four strains. The SNP-based phylogeny revealed close relationship among isolates from this study and other Bti isolates, and SNPs analysis of the plasmids 127 kb did not reveal any mutations in δ-endotoxins genes. This newly acquired sequence data for these Bti strains may be useful in the search for novel insecticidal toxins to improve existing ones or develop new strategies for the biological control of important insect vectors of human and animal diseases. [ABSTRACT FROM AUTHOR]

It has now been over a year since SARS-CoV-2 first emerged in China, in December 2019, and it has spread rapidly around the world. Some variants are currently considered of great concern. We aimed to analyze the numbers of SARS-CoV-2 genome sequences obtained in different countries worldwide until January 2021. On 28 January 2021, we downloaded the deposited genome sequence origin from the GISAID database, and from the "Our world in data" website we downloaded numbers of SARS-CoV-2-diagnosed cases, numbers of SARS-CoV-2-associated deaths, population size, life expectancy, gross domestic product (GDP) per capita, and human development index per country. Files were merged and data were analyzed using Microsoft Excel software. A total of 450,968 SARS-CoV-2 genomes originating from 135 countries on the 5 continents were available. When considering the 19 countries for which the number of genomes per 100 deaths was >100, six were in Europe, while eight were in Asia, three were in Oceania and two were in Africa. Six (30%) of these countries are beyond rank 75, regarding the human development index and four (20%) are beyond rank 80 regarding GDP per capita. Moreover, the comparisons of the number of genomes sequenced per 100 deaths to the human development index by country show that some Western European countries have released similar or lower numbers of genomes than many African or Asian countries with a lower human development index. Previous data highlight great discrepancies between the numbers of available SARS-CoV-2 genomes per 100 cases and deaths and the ranking of countries regarding wealth and development. [ABSTRACT FROM AUTHOR]