Department of Communicable Diseases, Interactive Research School for Health Affairs (IRSHA), Bharati Vidyapeeth (Deemed to be University), Katraj-Dhankawadi, Pune, 411043, India.
Eur J Clin Microbiol Infect Dis. 2020 Oct;39(10):1925-1932. doi: 10.1007/s10096-020-03933-5. Epub 2020 Jun 5.
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-PRNT 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 2005-2006 年时隔 32 年后在印度再次出现，并在浦那建立了地方性。为了评估 CHIKV 暴露程度，我们估计了浦那人群中按年龄分层的 IgG 抗体流行率。这项回顾性研究利用了 2017 年从浦那的 15 个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 个样本。在同一人群中比较了 CHIKV 和 DENV 的暴露情况。采用 CHIKV 特异性蚀斑减少中和试验（PRNT）评估 ELISA 阳性和抗 CHIKV-IgG 抗体的中和潜力。间接 ELISA 与商业 ELISA 具有 98.5%的一致性。CHIKV 的血清阳性率为 46.4%，三分之一的<15 岁儿童抗体呈阳性。在 16-25 岁年龄组中观察到显著增加（45%，p=0.026-0.038），在 65 岁及以上年龄组中降低（41%，p=0.01）。在儿童中，CHIKV-PRNT 滴度随年龄增加而增加，在 11-15 岁至>65 岁年龄组之间保持相当。DENV 的暴露率高于 CHIKV。儿童和老年人的暴露率较低可能是由于接触媒介的机会较少。在规划 CHIKV 疫苗研究时，需要解决 IgG 抗体高流行率的问题。
