Cross-sectional study uncovers high dengue and chikungunya seropositivity in low-income urban residents, highlighting differential serotype antibody waning and household risk factors.
Key Points
To determine the seroprevalence, determinants, and longitudinal neutralizing antibody kinetics of dengue virus (DENV) and chikungunya virus (CHIKV) in an urban low-income population.
Conducted a cross-sectional serosurvey with a nested longitudinal sub-study among 752 participants aged ≥2 years in an urban resettlement and slum settlement in Delhi, India.
Screened participants for anti-DENV and anti-CHIKV IgG antibodies using indirect enzyme-linked immunosorbent assay (ELISA).
Assessed functional antibody neutralization dynamics over time across a longitudinal subset of 100 paired IgG-positive samples using a micro-plaque reduction neutralization test (µPRNT50).
Seroprevalence was 81.91% (95% CI: 78.97, 84.60; n = 616) for DENV IgG and 28.32% (95% CI: 25.13, 31.69; n = 213) for CHIKV IgG.
µPRNT50 demonstrated stable CHIKV (97% to 98%), DENV-1 (76%), and DENV-2 (77% to 80%) neutralization, but revealed significant antibody contraction for DENV-3 (79% to 60%) and DENV-4 (69% to 60%).
Screened windows reduced odds of DENV (AOR: 0.36; 95% CI: 0.21, 0.61) and CHIKV (AOR: 0.63; 95% CI: 0.43, 0.90), while uncovered stagnant water containers increased CHIKV risk (AOR: 1.55; 95% CI: 1.05, 2.29).