Difference between Zika, Dengue, Chikungunya

• Chikungunya – an alphavirus that in the same family with Eastern and Western Equine Encephalitis viruses. Not related to dengue or Zika virus.
• Dengue – a flavivirus, is in the same family with numerous pathogens including Yellow Fever, Japanese encephalitis, St Louis encephalitis, tick borne encephalitis, West Nile and Zika viruses
• Zika – another flavivirus that is closely related to dengue and often misdiagnosed as dengue or chikungunya.

The illnesses caused by these three diseases have very similar/overlapping clinical presentation with prominent fever, headache, rash, myalgias (muscle aches) and arthralgias (joint aches).

In fact, serologic (antibodies in blood) surveys have demonstrated that outbreaks attributed to dengue in the past have turned out to be chikungunya or Zika infections.

Dengue and chikungunya are genetically distant relatives but Zika virus is closely related to dengue and often cross reacts (i.e. gives a false positive dengue test) on dengue serology or on some rapid assays that are available at some posts.