The immunopathology of dengue and Zika virus infections

- Immunopathogenesis is thought to play a substantial role in DENV disease.
- In recent years ZIKV outbreaks causing serious complications have occurred.
- These outbreaks are occurring in areas of DENV transmission.
- Sequence homology between ZIKV and DENV leads to cross-reactive immunity.
- The consequences of ZIKV/DENV cross-reactivity require thorough investigation.

A large proportion of the world's population live in areas with dengue virus (DENV) transmission resulting in tens of millions of symptomatic dengue cases each year. Serious complications following DENV infection occur more frequently in those suffering from a second or subsequent infection implicating virus-specific immunity as having a role in pathogenesis. In recent years outbreaks of the related Zika virus (ZIKV) have been associated with birth defects and neurological complications. As DENV and ZIKV share a viral vector sequential infections can occur. Given the sequence homology between the two viruses, the generation of cross-reactive immune responses is highly likely. This review examines the role immunopathogenesis plays during DENV infection as well as highlighting recent studies that demonstrate DENV immunity may have an effect on the outcome of ZIKV infection.