Molecular characterization and sequecing analysis of SARS-CoV-2 genome in Minas Gerais, Brazil

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), first identified in Wuhan, China, is the causative agent of the coronavirus disease 2019 (COVID-19). Since its first notification in São Paulo state (SP) on 26th February 2020, more than 22,300,000 cases and 619,000 deaths were reported in Brazil. In early pandemic, SARS-CoV-2 spread locally, however, over time, this virus was disseminated to other regions of the country. Herein, we performed genomic sequencing and phylogenetic analysis of SARS-CoV-2 using 20 clinical samples of COVID-19 confirmed cases from 9 cities of Minas Gerais state (MG), in order to evaluate the molecular properties of circulating viral strains in this locality from March to May 2020. Our analyses demonstrated the circulation of B.1 lineage isolates in the investigated locations and nucleotide substitutions were observed into the genomic regions related to important viral structures. Additionally, sequences generated in this study clustered with isolates from SP, suggesting a dissemination route between these two states. Alternatively, monophyletic groups of sequences from MG and other states or country were observed, indicating independent events of virus introduction. These results reinforce the need of genomic surveillance for understand the ongoing spread of emerging viral pathogens.

Occurrence, removal and seasonal variation of pharmaceuticals in Brasilian drinking water treatment plants

The presence of pharmaceuticals in aquatic environments has become a major issue of concern for scientific community, since there is a lack of information about risks and impacts to the environment and public health. In the context of Brazil, many cities do not have Wastewater Treatment Plants (WWTPs) and domestic sewage is dumped directly into the water bodies, aggravating the problem. Thus, the present study aimed to evaluate the presence of 28 prescribed pharmaceuticals from different therapeutic classes in six full-scale Drinking Water Treatment Plants (DWTPs) in Minas Gerais state. Samples were collected in twelve field campaigns from August 2016 to August 2017 and water quality were monitored. Analytical methodology was based on solid phase extraction (C18 cartridge) followed by High Performance Liquid Chromatography (Prominence DGU/20A3 - Shimadzu) coupled to Mass Spectrometry (micrOTOF-QII - Bruker). Considering the 28 pharmaceuticals analyzed, 18 were detected in the surface water source at concentrations ranging from Method Quantification Limit (MQL) to 11,960 ng/L. In drinking water, the concentration of the 11 pharmaceuticals detected ranged from <MQL to 6323 ng/L. Betamethasone, Fluconazole, Atorvastatin and Prednisone were the most detected pharmaceuticals. The drinking water monitoring showed a decrease in the concentration of all detected pharmaceuticals, indicating some removal of these compounds by the water treatment processes. The removal efficiency assessed shows a great variation among different compounds, DWTPs and over the year, ranging from an average of 32% ± 6% (Prednisone -DWTP3) to 100% ± 0% for some pharmaceuticals. The highest total concentrations and the maximum concentration values for the most frequently detected pharmaceuticals were related to the winter due, presumably, to lower dilution and temperature. Trace levels of pharmaceuticals were detected in surface and drinking water in Brazil and conventional DWTPs were not able to remove the pharmaceuticals completely.