Co-infection with Stealth Adapted Viruses May Explain Zika Virus Associated Microcephaly

The apparent association of Zika virus infection with microcephaly appears to be largely confined to Brazil. While this could be due to genetic changes in the Brazilian Zika virus, it is also consistent with a facilitating effect of co-infection with another virus. Public health authorities have been reluctant to acknowledge the presence of stealth adapted viruses [1]. These viruses have deletions or mutations in the relatively few components in viruses that are normally targeted by the cellular immune system [2]. Consequently, stealth adapted viruses do not evoke an inflammatory response; the hallmark of an infectious process [3].