Most Zika virus infections are either asymptomatic or cause a mild illness with a transient maculopapular rash. However, there is scientific consensus that Zika virus is a cause of microcephaly, congenital nervous system malformations and Guillain-Barré syndrome.
Chikungunya is a viral disease transmitted by Aedes mosquitoes to humans. The word ‘chikungunya’ means 'that which bends up', an allusion to the posture of the suffering patients. The most common symptom is joint pain.