10 Solid links between the Zika Virus and Neurological Defects

While the world waits for proof that Zika Virus (ZIKV) causes neurological defects, most notably, microcephaly in children, the circumstantial evidence is mounting. Many empirical, scientific and even theoretical linkages exist between Zika fever and neurological complications.

Empirical – Observed links between ZIKV

1. Microcephaly cases have skyrocketed in Brazil during the current outbreak. With close to 5000 suspected or confirmed cases, the rate is 8-10 fold of the expected rate.
2. Besides microcephaly, clinical examination has found numerous other neurological complications in fetuses, and even ocular abnormalities
3. Cases of microcephaly have now been diagnosed in other Zika fever affected countries, including retroactively in the French Polynesian outbreak.
4. The yap island outbreak of 2012 had elevated levels of Guillain-Barre syndrome – also a neurological condition.

Scientific – Research findings linking ZIKV to neurological conditions

1. ZIKV has been found to infect human neuroprogenitor cells (hNPCs) – key elements in fetal brain development.
2. Fetal autopsies have revealed the presence of ZIKV in brain tissue
3. Zika Virus has been found in amniotic fluid
4. The AXL cell receptors, believed to be the main path of entry for ZIKV in hNPCs, also exist on fibroblast cells in the skin. Fibroblasts have also been shown to be permissive to Zika virus.

Theoretical – Similarities

1. ZIKV seems to share many similarities in pathology with other Flaviviruses like dengue, Japanese encephalitis and West Nile. Many of these have proven affects on the nervous system.
2. ZIKV is an arbovirus, which are known to cause encephalitis. Encephalitis means an inflammation of the brain!

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