Fig 2. Dot plot of chikungunya virus (CHIKV) plaque reduction neutralization test (PRNT) titers at enrollment and 12 months in per-protocol subjects.

All 19 symptomatic and 87 subclinical CHIKV infections had enrollment PRNT titer <10 and 12-month titers ranging from 229 to 2,030 in symptomatic infections and 64 to 3,347 in subclinical infections; 239 subjects had positive titers at enrollment ranging from 10 to 1,785; and 505 subjects had negative titers at both enrollment and 12 months.