Disability with Persistent Pain Following an Epidemic of Chikungunya in Rural South India

Objective. We investigated the effects of chronic rheumatic and musculoskeletal symptoms on the functional status of people affected by the chikungunya (CKG) epidemic in the Calicut District, Kerala, South India in 2009. Methods. A cross-sectional house-to-house survey was conducted 18 months after the CKG epidemic to assess functional status of individuals with post-epidemic persistent pain. All respondents over age 15 years with persistent pain fitting the epidemiological case definition were included. Participants' functional status was assessed using the Health Assessment Questionnaire-Disability Index (HAQ-DI). Factors affecting severity of HAQ-DI were analyzed by ordinal regression. Results. Of 3869 subjects interviewed, 1195 (34.3%) had a positive history of CHIKV virus infection (epidemiological or confirmed); 36.28% (624/1720) of CKG-affected individuals had persistent pain 18 months post epidemic. Mean age of those affected was 48.22 +/- 15.6 years; 23.2% had no disability, while 16.2% had moderate to severe disability on the HAQ-DI. Significant factors affecting severity of disability on HAQ-DI included previous rheumatic musculoskeletal disease (OR 2.27), joint and soft-tissue involvement (OR 3.74), only joint involvement (OR 2.14), female sex (OR 1.44), diet (OR 4.73), and history of joint swelling (OR 1.72). Conclusion. Persistence of pain noted in post-CKG disease resulted in significantly deteriorated functional status of those affected.