Volume 22, Number 10—October 2016
Letter
Resolution of a Chikungunya Outbreak in a Prospective Cohort, Cebu, Philippines, 2012–2014
Table
Incidence of subclinical and symptomatic chikungunya virus infection during 2 years of active surveillance in an age-stratified cohort, Cebu, Philippines, 2012–2014*
Only persons with negative neutralizing antibodies at beginning of 2nd year, by age | ||||
---|---|---|---|---|
6 mo–5 y | 2/1.84 (0.37–5.89) | 1/0.92 (0.08–4.28) | 3/2.76 (0.76–7.35) | |
6–15 y | 1/0.77 (0.07–3.6) | 3/2.32 (0.64–6.18) | 4/3.09 (1.03–7.35) | |
16–30 y | 1/1.15 (0.1–5.36) | 4/4.6 (1.54–10.94) | 5/5.75 (2.18–12.6) | |
31–50 y | 1/2.11 (0.19–9.82) | 4/8.43 (2.82–20.03) | 5/10.53 (3.99–23.09) | |
>50 y | 1/2.05 (0.19–9.55) | 3/6.15 (1.7–16.4) | 4/8.2 (2.74–19.49) | |
All ages | 6/1.42 (0.59–2.93) | 15/3.56 (2.08–5.72) | 21/4.98 (3.18–7.47) |
Bold indicates significantly different (p<0.05) from incidence observed among the corresponding age groups during the first year of surveillance. Prevalence of neutralizing antibodies at the beginning of the first year was 28% and at the beginning of the second year was 42%.
1Current affiliation: International Vaccine Institute, Seoul, South Korea.