Leishmaniasis is a wide-spectrum disease caused by parasites from Leishmania genus. There is no human vaccine available and it is considered by many studies as apotential effective tool for disease control. To discover novel antigens, computational programs have been used in reverse vaccinology strategies. In this work, we developed a validation antigen approach that integrates prediction of B and T cell epitopes, analysis of Protein-Protein Interaction (PPI) networks and metabolic pathways. We selected twenty candidate proteins from Leishmania tested in murine model, with experimental outcome published in the literature. The predictions for CD4⁺ and CD8⁺ T cell epitopes were correlated with protection in experimental outcomes. We also mapped immunogenic proteins on PPI networks in order to find Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways associated with them. Our results suggest that non-protective antigens have lowest frequency of predicted T CD4⁺ and T CD8⁺ epitopes, compared with protective ones. T CD4⁺ and T CD8⁺ cells are more related to leishmaniasis protection in experimental outcomes than B cell predicted epitopes. Considering KEGG analysis, the proteins considered protective are connected to nodes with few pathways, including those associated with ribosome biosynthesis and purine metabolism.

In view of current COVID-19 pandemic scenario, uncertainties still remains around the role of domestic animals on COVID-19 epidemiology, this systematic review aims to present the scientific evidence available, so far, on dogs and cats epidemiological role in the COVID-19 pandemic. The systematic review was conducted in accordance with the recommendations of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses – PRISMA. Selected studies reports negative results of dogs and cats both in serological tests, for the detection of neutralizing antibodies, and in tests that investigated the presence of the SARS-CoV2 RNA. We verified the lack of national studies, which serves as a motivation for more research to be carried out in Brazil. In Brazil, in the animals tested, 5.4 and 6.2% of cats and dogs were positive, respectively. Few studies, so far, have been carried out with stray animals or animals belonging to shelters. This absence of broad conducted studies on animal interface enphasizes the need for more research with animals in vulnerable conditions, since they can contribute to the spread of the disease if they are confirmed as positive for SARS-COV-2. The compilation of data, through this systematic review of the literature, to date suggests that dogs and cats are not factors of viral spread to humans. However, further studies are still recommended.