Search bioRxivSearch

Biology subjects

Amadou Alpha Sall

Publications and source records attributed to Amadou Alpha Sall.

2 recordsLinked to original sources

A Zika virus-associated microcephaly case with background exposure to STORCH agents

We present a case of microcephaly associated with Zika virus (ZIKV) in a chronological, multimodal imaging approach, illustrating the hallmarks of this disease on intrauterine morphological ultrasound, transfontanelar ultrasound, computed tomography (CT) and magnetic resonance imaging (MRI). We also determined the serological e immunological status of the mother and newborn. Noticeably, there was evidence for maternal infection by ZIKV, cytomegalovirus (CMV), herpes simplex virus (HSV), dengue virus (DENV) and Toxoplasma gondii, which indicates a possible role of previous exposures to STORCH agents and possibly comorbidities in the severe fetal congenital manifestation.\n\nAuthor SummaryZika virus (ZIKV) is an emerging mosquito-borne arbovirus causing dengue-like symptoms. In humans the illness is characterized by malaise and cutaneous rash and absent or short-termed fever. Recently, the Brazilian Ministry of Health reported an outbreak of microcephaly in Brazil as a delayed effect of the 2014-2015 outbreak of ZIKV in the Northeast of Brazil. A 20-fold increase in the notifications of newborns with microcephaly was documented during the second semester of 2015. This increase was almost immediately found to be associated with ZIKV infections, both in Brazil and, retrospectively, in French Polynesia. Herein we report a case of microcephaly associated with ZIKV and we also present evidence of other maternal infections. Our results indicated that, both mother and microcephaly infant had immunologic status compatible with previous exposure (in the mother) by STORCH agents. These indicate a possible role of previous exposures and possibly comorbidities in the severe fetal congenital manifestation. {square}

Microbiology

Spread of the pandemic Zika virus lineage is associated with NS1 codon usage adaptation in humans

Zika virus (ZIKV) infections were more common in the zoonotic cycle until the end of the 20th century with few human cases in Africa and Southeastern Asia. Recently, the Asian lineage of ZIKV is spreading along human-to-human chains of transmission in the Pacific Islands and in South America. To better understand its recent urban expansion, we compared genetic differences among the lineages. Herein we show that the recent Asian lineage spread is associated with significant NS1 codon usage adaptation to human housekeeping genes, which could facilitate viral replication and increase viral titers. These findings were supported by a significant correlation with growth in Malthusian fitness. Furthermore, we predicted several epitopes in the NS1 protein that are shared between ZIKV and Dengue. Our results imply in a significant dependence of the recent human ZIKV spread on NS1 translational selection.

Microbiology