Zika virus infection acquired during pregnancy was associated with congenital microcephaly. We describe two cases of ZIKV infection in the 36th week of pregnancy whose fetuses had preserved head circumference at birth and findings of subependymal cysts and lenticulostriate vasculopathy in postnatal imaging. These represent the first signs of congenital brain injury acquired due to ZIKV in the third trimester.
Showing the closest link yet between Zika virus and fetal brain injury in an animal model that closely resembles humans, researchers today described brain abnormalities in the fetus of a macaque experimentally infected during the late stage of her pregnancy.
In other developments, Thailand reported several more Zika cases, many of them linked to a cluster in Bangkok, as the number of infections in Singapore grew steadily. In Florida, health officials denied a newspaper report charging problems with Zika reporting, and Broward County began aerial spraying withan organic pesticide as a prevention step.
Um estudo brasileiro publicado na revista Clinical Infectious Diseases revelou que a infecção de gestantes pelo vírus Zika pode representar um risco para o desenvolvimento neurológico dos bebês mesmo quando ocorre poucos dias antes do nascimento.
“Predominava, até então, o paradigma de que a infecção seria preocupante somente se ocorresse no primeiro trimestre da gestação. No entanto, observamos danos cerebrais em quatro crianças cujas mães foram infectadas faltando entre duas e uma semana para o parto”, afirmou Maurício Lacerda Nogueira, professor da Faculdade de Medicina de São José do Rio Preto (Famerp) e integrante da Rede de Pesquisa sobre Zika Vírus em São Paulo (Rede Zika).
Given the huge burden that Chikungunya and Zika fevers impose to public health in the affected countries and the lack of effective interventions against them, the aim of this work was to evaluate the antiviral potential of bovine lactoferrin (bLf) – an iron-binding glycoprotein with broad-spectrum antimicrobial properties – in both CHIKV and ZIKV infections. The general antiviral activity of bLf was assessed by plaque assays, and the inhibitory effects of the protein on specific stages of virus infecion was evaluated by immunofluorescence and nucleic acid quantification assays. Our data show that bLf exerts a dose-dependent strong inhibitory effect on the infection of Vero cells by the aforementioned arboviruses, reducing their infection efficiency in up to nearly 80%, with no significant cytotoxicity, and such antiviral activity occurs at the levels of binding and replication of the virus particles. Taken together, these findings reveal that bLf antimicrobial properties are extendable to CHIKV and ZIKV, underlining a generic inhibition mechanism that can be explored to develop a potential strategy against their infections.
A rapid point-of-care test is needed to detect the virus, especially at low resource settings. Methodology/Principal Findings: In this report, we describe the development of a reverse transcription isothermal recombinase polymerase amplification (RT-RPA) assay for the identification of ZIKV. RT-RPA assay was portable, sensitive (21 RNA molecules), and rapid (3-15 minutes). No cross-reactivity was detected to other flaviviruses, alphaviruses and arboviruses. Compared to real-time RT-PCR, the diagnostic sensitivity was 92% while the specificity was 100%. Conclusions/Significance: The developed assay is a promising platform for rapid point of need detection of ZIKV in low resource settings and elsewhere (e.g. during mass gathering).
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O vírus Zika é capaz de bloquear a ativação do sistema imunológico da pessoa infecctada. A constatação veio a partir do mapeamento genético do vírus que circula em Pernambuco, sequenciado pela primeira vez no estado por pesquisadores da Fundação Oswaldo Cruz (Fiocruz) de Pernambuco em parceria com profissionais da Universidade de Glasgow, no Reino Unido.
O artigo com os resultados foi publicado ontem (5) na revista PLOS Neglected Tropical Disease. O sequenciamento genético foi realizado a partir de uma amostra coletada de um paciente infectado em 2015, no início da epidemia.
De acordo com o pesquisador da Fiocruz Rafael França, um dos responsáveis pela pesquisa, uma pequena parte da carga genética do Zika pode bloquear a ativação de um componente do sistema imune considerado importante para combater infecções virais: o interferon, que combate a replicação do vírus. “Se o Zika bloqueia a produção desses interferons ele vai conseguir replicar, então ele vai ter um processo infeccioso melhor, vai conseguir infectar muito mais a célula, vai ser mais agressivo”, disse França.
The full-length genome sequence including non-coding regions of a South American ZIKV isolate from a patient with classical symptoms will support efforts to develop genetic tools for this virus. Detection of sfRNA that counteracts interferon responses is likely to be important for further understanding of pathogenesis and virus-host interactions.
Umas poucas dezenas de pessoas nos Estados Unidos e no Canadá receberam as primeiras doses de duas formulações candidatas a vacina contra o vírus zika nas últimas semanas. Essa é a primeira vez que potenciais vacinas contra o zika são testadas em seres humanos. Ambas as formulações são o que os pesquisadores chamam de vacina de DNA e apresentam composição semelhante: elas contêm cópias sintéticas de um trecho do material genético do vírus que codifica duas proteínas que o recobrem externamente, a proteína pré-membrana (prM) e a proteína do envelope (E), a partir das quais as células de defesa do organismo identificam o invasor.
Zika virus is related to dengue virus, and here we report that a subset of antibodies targeting a conformational epitope isolated from patients with dengue virus also potently neutralize Zika virus. The crystal structure of two of these antibodies in complex with the envelope protein of Zika virus reveals the details of a conserved epitope, which is also the site of interaction of the envelope protein dimer with the precursor membrane (prM) protein during virus maturation. Comparison of the Zika and dengue virus immunocomplexes provides a lead for rational, epitope-focused design of a universal vaccine capable of eliciting potent cross-neutralizing antibodies to protect simultaneously against both Zika and dengue virus infections.
To aid in the development of antivirals, we present two high-resolution crystal structures of the ZIKV NS5 methyltransferase: one bound to S-adenosylmethionine (SAM) and the other bound to SAM and 7-methyl guanosine diphosphate (7-MeGpp). We identify features of ZIKV NS5 methyltransferase that lend to structure-based antiviral drug discovery. Specifically, SAM analogs with functionalities on the Cβ atom of the methionine portion of the molecules that occupy the RNA binding tunnel may provide better specificity relative to human RNA methyltransferases.
