Table 2 Chikungunya case definition

Clinical criteria

Acute onset of fever > 38.5 °C and severe arthralgia/arthritis not explained by other medical conditions

Epidemiological criteria

Residing or having visited epidemic areas having reported transmission within 15 days prior to the onset of symptoms

Laboratory criteria

Virus isolation

Presence of viral RNA by RT-PCR

Presence of virus-specific IgM antibodies in single serum sample collected in acute or convalescent stage

Four-fold increase in IgG values in samples collected at least 3 weeks apart

Suspect case

Any person with acute onset of fever > 38.5 °C and severe arthralgia/arthritis not explained by other medical conditions

Probable case

A patient meeting both the clinical and epidemiological criteria

Confirmed case

A suspected case with laboratory confirmation