Chikungunya (CHIKV) reemerged in India after a gap of 32 years, in 2005–2006 and has established endemicity in Pune. To assess the degree of CHIKV exposure, we estimated age-stratified prevalence of IgG antibodies to CHIKV in Pune population. This retrospective study utilized age-stratified serum samples collected from 15 wards of Pune in 2017 for dengue (DENV) virus study. Indirect anti-CHIKV-IgG ELISA was developed and used to test 1904 samples. Exposure to CHIKV and DENV was compared in the same population. CHIKV-specific plaque reduction neutralization test (PRNT) was employed to evaluate ELISA positivity and neutralizing potential of anti-CHIKV-IgG antibodies. Indirect ELISA showed 98.5% concordance with commercial ELISA. Seropositivity to CHIKV was 46.4%, one-third children < 15 years being antibody positive. A significant increase (45%, p = 0.026–0.038) was noted at 16-25 years and varied between 48 and 56% until the age 65. In elderly (65 + years), antibody positivity was reduced (41%, p = 0.01). In children, CHIKV-PRNT₅₀ titers increased with age and remained comparable from the age group 11-15 until > 65. Exposure to DENV was higher than CHIKV. Lower exposure of children and elderly could be due to lesser exposure to the vectors. High prevalence of IgG antibodies needs to be addressed while planning vaccine studies for CHIKV.

基孔肯雅热（CHIKV）在隔了32年之后于2005年至2006年在印度重新崛起，并在浦那建立了流行性。为了评估CHIKV暴露的程度，我们估计了浦那人群中针对CHIKV的IgG抗体的年龄分层患病率。这项回顾性研究利用了2017年从浦那15个病区收集的按年龄分层的血清样本进行登革热（DENV）病毒研究。开发了间接抗CHIKV-IgG ELISA，并用于测试1904个样品。比较了同一人群中CHIKV和DENV的暴露情况。采用CHIKV特异性空斑减少中和试验（PRNT）评估抗CHIKV-IgG抗体的ELISA阳性和中和潜力。间接ELISA显示与商业ELISA的98.5％一致性。对CHIKV的血清阳性率为46.4％，三分之一的儿童<15年为抗体阳性。在16-25岁时显着增加（45％，p = 0.026-0.038），直到65岁时在48％至56％之间变化。在老年人（65岁以上）中，抗体阳性率降低（41％，p = 0.01）。在儿童中，CHIKV-PRNT ₅₀滴度随着年龄的增长而增加，并且在11-15岁年龄组直至65岁之间仍保持可比性。DENV的暴露水平高于CHIKV。儿童和老人的较低接触可能是由于较少接触这些载体。在规划针对CHIKV的疫苗研究时，需要解决IgG抗体高流行的问题。