Natural Products and Derivatives as Potential Zika virus Inhibitors: A Comprehensive Review.

Zika virus (ZIKV) is an arbovirus whose infection in humans can lead to severe outcomes. This article reviews studies reporting the anti-ZIKV activity of natural products (NPs) and derivatives published from 1997 to 2022, which were carried out with NPs obtained from plants (82.4%) or semisynthetic/synthetic derivatives, fungi (3.1%), bacteria (7.6%), animals (1.2%) and marine organisms (1.9%) along with miscellaneous compounds (3.8%). Classes of NPs reported to present anti-ZIKV activity include polyphenols, triterpenes, alkaloids, and steroids, among others. The highest values of the selectivity index, the ratio between cytotoxicity and antiviral activity (SI = CC50/EC50), were reported for epigallocatechin gallate (SI ≥ 25,000) and anisomycin (SI ≥ 11,900) obtained from Streptomyces bacteria, dolastane (SI = 1246) isolated from the marine seaweed Canistrocarpus cervicorni, and the flavonol myricetin (SI ≥ 862). NPs mostly act at the stages of viral adsorption and internalization in addition to presenting virucidal effect. The data demonstrate the potential of NPs for developing new anti-ZIKV agents and highlight the lack of studies addressing their molecular mechanisms of action and pre-clinical studies of efficacy and safety in animal models. To the best of our knowledge, none of the active compounds has been submitted to clinical studies.

Rate of exposure to Mayaro virus (MAYV) in Brazil between 1955 and 2018: a systematic review and meta-analysis.

Mayaro fever is an infection caused by Mayaro virus (MAYV) that stands out among the neglected diseases transmitted by arthropods. Brazil is the country with the highest number of confirmed cases of MAYV infection. However, epidemiological surveillance studies conducted in Brazil are decentralized and focus on small outbreaks and unconfirmed cases. Thus, the aim of this review was to determine the general epidemiological profile of MAYV infections in Brazil. Several medical databases (i.e., PUBMED/MEDLINE, Scopus, Cochrane Library, LILACS, SciELO, and Biblioteca Virtual em Saúde) were searched for studies reporting cases of MAYV infections in Brazilian patients. Then, the rate of exposure to MAYV in Brazil was analyzed using RStudio® Software. We identified 37 studies published from 1957 to 2019, containing data of 12,374 patients from 1955 to 2018. The general rate of exposure to MAYV in Brazil was 10% (95% CI; 0.04-0.22), with 1,304 reported cases. The highest incidence of MAYV infection was found in the northern region (13%; 95% CI; 0.05-0.29), with 1,142 cases (88% of all cases). Furthermore, autochthonous MAYV cases have also been reported in the Central West (8%; 95% CI; 0.03-0.18) and Southeast (0.4%; 95% CI; 0.00-0.28). The states with the highest number of cases are Amazonas (490 cases), Pará (276 cases), and Goiás (87 cases). In conclusion, the general rate of exposure to MAYV in Brazil between 1955 and 2018 was considerable, especially in the Legal Amazon, in which 93% of cases were reported.