Lyme Borreliosis, a public health concern in India: Findings of serosurvey from two states.

Background: Lyme borreliosis is a public health concern in India. The prevalence of the disease is still undetermined with major entomological and epidemiological gaps. The present study was conducted to determine the seropositivity of in Sikkim and Arunachal Pradesh, India.

Methods: A cross-sectional serosurvey was conducted in Sikkim and Arunachal Pradesh. Data collection tools were developed and standardized for the collection of clinico-socio-demographic data. Sample size for each site was calculated using the formula for the estimation of a single proportion. Qualitative detection of IgG antibodies in serum samples was done using NovaLisa™ Lyme Borrelia IgG ELISA kit.

Results: A total of 793 participants were enrolled, 484 (61%) from Arunachal Pradesh and 309 (39%) from Sikkim. Out of 793 participants, 21 (2.7%), 22 (2.8%), 6 (0.8%), 29 (3.7%), 44 (5.5%), and 16 (2.1%) gave history of tick bite, rash, , migratory muscle pain, migratory joint pain, and numbness, respectively, in the past one year. The adjusted seroprevalence (for sensitivity and specificity of kit) for the study is 3.7 (2.4-5.2). No signs or symptoms were found to be associated with IgG ELISA positivity. The state-wise distribution of seropositivity for Arunachal Pradesh and Sikkim was 4.1 (95% CI: 2.5-6.3) and 2.3 (95% CI: 0.9-4.6), respectively.

Conclusion: This study establishes the state of Sikkim as a new endemic area in India of Lyme disease besides its already reported endemicity in Arunachal Pradesh. No association was conclusively established between symptoms of Lyme and IgG seropositivity emphasizing the need for detailed history taking and clinical suspicion in endemic areas.