Evolutions and upcoming on Zika virus diagnosis through an outbreak: A systematic review.

Zika virus (ZIKV) is an enveloped, positive single-stranded sense RNA virus transmitted by Aedes species. Many efforts have been conducted to find a good, reliable and cost-effective test for ZIKV diagnosis. Diagnosis is still imprecise, expensive and there is not a standard model. We investigated the publications on ZIKV diagnostics and analyzed varieties of diagnostic methods, sensibility, specificity, and the evolution of new methodologies. Conducted in accordance with the PRISMA-P statement, three blocks of MeSH terms were assembled: group I: virus infection; group II: diagnostic methodologies; group III: characteristics and varieties on diagnostic methods. Search was performed on PubMed, Web of Science and SCOPUS databases. Eighteen articles were retrieved, reporting serological and molecular diagnostic techniques. Serum was used as the main biological material in the serological diagnosis, but urine and sperm were presented as an alternative. Molecular methods used structural and nonstructural regions of ZIKV genome. Experimental methodologies were more efficient, faster, and cheaper. Serological tests are faster and less expensive than molecular assays, but molecular assays are more specific. The use of both methodologies would be the most appropriate and reliable way to obtain correct diagnostic results.

Genetic characterization of Chikungunya virus circulating in individuals from Paraná, Brazil.

Phylogenetic analysis carried out in several Brazilian regions shows the circulation of the Asian and East-Central South African (ECSA) Chikungunya virus (CHIKV) genotypes in the country. Until now, there are no genetic studies about CHIKV strains circulating in the South region. In this study, we sequenced 5 new partial sequences of the CHIKV Envelope 1 gene from strains detected in Paraná state during the years 2016-2017. Maximum likelihood and neighbor-joining trees grouped all sequences in Brazilian branches within ECSA genotype and comparative analysis did not show E1-A226V mutation. However, we identified E1-K211T amino acid substitution in a sample demonstrating the dispersion of mutant strains in the country.

Insights on Zika virus envelope gene conservation in American outbreaks.

Phylogenetic studies with Zika virus (ZIKV) have been conducted in Brazil. In this study, we sequenced 8 new sequences of the ZIKV envelope (E) gene from strains of cases from the Paraná and Mato Grosso do Sul states in 2016. A low phylogenetic signal was observed, with more than 40% of unresolved quartets, and the Maximum Likelihood Tree grouped all sequences in the Brazilian branches within the Asian genotype. In addition, a Shannon entropy analysis was conducted, showing a high stability in the E protein through the ZIKV polyprotein. Taken together, these results suggest a high degree of conservation in the ZIKV E gene from the recent American outbreaks.