Zika virus and diagnostics

The purpose of this review is to present what is known about the Zika virus (ZIKV) at the time of writing this review. The viral structure and its phylogeny, as well as the limitations of current available techniques used for diagnosis, are discussed.

Crystallography and cryo-electron microscopy of the whole ZIKV, or a few of its proteins, are confirming its overall antigenic relatedness to other flaviviruses. Sequencing has revealed its dynamic genetic variation and has placed the Western cluster of Zika isolates within the Asian phylogenic tree. Genetic codon mutations, although highly prevalent, do not usually translate into modifications at amino acid or proteomic levels, revealing conserved enzymatic functions that could potentially be addressed therapeutically. Clinical characterization of ZIKV infection is complicated because of symptoms similar to dengue and chikungunya. Diagnosis requires specialized laboratories with costly reagents and highly trained personnel. Although commercial labs are now offering ZIKV diagnostic tests, most of them are not fully tested in comparison with standard molecular techniques standardized at CDC and local health departments. We are still in desperate need of simpler diagnostic tests that better discriminate ZIKV from coendemic arboviruses.

The area of better Zika diagnostic assays is a rapidly developing field with the public attention directed to this epidemic. Academic interest in this topic is driving fast disclosure of information in peer-reviewed journals and grey papers via web-based forums. We expect in the near future that new promising strategies for improved Zika diagnostics will translate into preventive and therapeutic tools.