Breakdown of arboviruses associated with febrile illness, by location, 2000–2007.

1Confirmed cases (virus isolation, RT-PCR, or IgM seroconversion).2Presumptive cases (elevated IgM without 4-fold rise between acute and convalescent).3Percent of total febrile cases from this location.4Many of the participants with YFV-reactive serum are likely due to recent vaccination or Flavivirus cross-reactivity, and thus are not reflective of natural YFV infection (see text).5Only limited serologic testing for GROV IgM was performed prior to 2007.Virus isolates (Table 4) are included with the confirmed diagnoses.