Epidemiology and evolution of Zika virus in Minas Gerais, Southeast Brazil

Analyses of Early ZIKV Genomes Are Consistent with Viral Spread from Northeast Brazil to the Americas

The Americas, particularly Brazil, were greatly impacted by the widespread Zika virus (ZIKV) outbreak in 2015 and 2016. Efforts were made to implement genomic surveillance of ZIKV as part of the public health responses. The accuracy of spatiotemporal reconstructions of the epidemic spread relies on the unbiased sampling of the transmission process. In the early stages of the outbreak, we recruited patients exhibiting clinical symptoms of arbovirus-like infection from Salvador and Campo Formoso, Bahia, in Northeast Brazil. Between May 2015 and June 2016, we identified 21 cases of acute ZIKV infection and subsequently recovered 14 near full-length sequences using the amplicon tiling multiplex approach with nanopore sequencing. We performed a time-calibrated discrete phylogeographic analysis to trace the spread and migration history of the ZIKV. Our phylogenetic analysis supports a consistent relationship between ZIKV migration from Northeast to Southeast Brazil and its subsequent dissemination beyond Brazil. Additionally, our analysis provides insights into the migration of ZIKV from Brazil to Haiti and the role Brazil played in the spread of ZIKV to other countries, such as Singapore, the USA, and the Dominican Republic. The data generated by this study enhances our understanding of ZIKV dynamics and supports the existing knowledge, which can aid in future surveillance efforts against the virus.

Burden in caregivers of children with congenital Zika syndrome in Pernambuco, Brazil: analysis and application of the Zarit burden interview scale

With the increase in cases of microcephaly caused by the Zika virus, the demand for special care and a better quality of life for the child and caregiver increased proportionally.

Objective

This study aimed to analyze the burden on caregivers of children with congenital Zika syndrome associated with viral infections in the state of Pernambuco, Brazil using the Zarit Burden interview scale.

Method

A quantitative study was conducted at the Oswaldo Cruz University Hospital, Recife City, State of Pernambuco, Brazil. By convenience sampling, 56 mothers, two grandmothers, and two caregivers were enrolled, all are female. Data were collected from July 2019 to January 2020. In the analysis, the percentage frequencies were calculated. The normality was identified using the Kolmogorov-Smirnov test, and participant profiles were compared using Student's t-test and analysis of variance. In descriptive statistics, quantitative variables are described by the median and interquartile range and categorical variables by proportions using the Chi-square test.

Results

In the comparative analysis, all factors evaluated were significant, except for the "gestational period in which the disease occurred" (p < 0.111). The significance of differences in all activities was evaluated. In the mean comparison test, only the factor "has a job" was significant (p < 0.043). When comparing the average of caregivers' responses to the categories of the Zarit burden interview scale, the highest level of burden was regarding the feeling that the child is dependent on the caregiver (3.62 points). Caregiver burden was classified as absence, light, moderate, and high.

Conclusion

The consequences of contracting the Zika virus in the first trimester of pregnancy, lack of paid work, financial scarcity, full-time dedication to the child, and lack of time for themselves increase the burden on caregivers. Thus, caregivers have mild burden.

Azelnidipine Exhibits In Vitro and In Vivo Antiviral Effects against Flavivirus Infections by Targeting the Viral RdRp

Flaviviruses, represented by Zika and dengue virus (ZIKV and DENV), are widely present around the world and cause various diseases with serious consequences. However, no antiviral drugs have been clinically approved for use against them. Azelnidipine (ALP) is a dihydropyridine calcium channel blocker and has been approved for use as an antihypertensive drug. In the present study, ALP was found to show potent anti-flavivirus activities in vitro and in vivo. ALP effectively prevented the cytopathic effect induced by ZIKV and DENV and inhibited the production of viral RNA and viral protein in a dose-dependent manner. Moreover, treatment with 0.3 mg/kg of ALP protected 88.89% of mice from lethal challenge. Furthermore, using the time-of-drug-addition assay, the enzymatic inhibition assay, the molecular docking, and the surface plasmon resonance assay, we revealed that ALP acted at the replication stage of the viral infection cycle by targeting the viral RNA-dependent RNA polymerase. These findings highlight the potential for the use of ALP as an antiviral agent to combat flavivirus infections.

The Ablation of Envelope Protein Glycosylation Enhances the Neurovirulence of ZIKV and Cell Apoptosis in Newborn Mice

Zika virus (ZIKV) has attracted the wide global attention due to its causal link to microcephaly. In this study, two amino acid (aa) mutation (E143K and R3394K) were identified at the fourth generation (named ZKC2P4) during the serial passage of ZIKV-Asian lineage ZKC2/2016 strain in the newborn mouse brain, while another seven aa deletions in envelope (E) protein were detected in ZKC2P6. ZKC2P6 is a novel nonglycosylated E protein Asian ZIKV we first identified and provides the first direct supporting evidence that glycosylation motif could be lost during the passage in neonatal mice. To study the impact of E protein glycosylation ablation, we compared the pathogenicity of ZKC2P6 with that of ZKC2P4. The results showed that the loss of E protein glycosylation accelerated the disease progression, as evidenced by an earlier weight loss and death, a thinner cerebral cortex, and more serious tissue lesions and inflammation/necrosis. Furthermore, ZKC2P6 exhibited a greater ability to replicate and caused severer cell apoptosis than that of ZKC2P4. Therefore, the ablation of E glycosylation generally enhances the neurovirulence of ZIKV and cell apoptosis in newborn mice.