Surveillance of Chikungunya virus activity in some North-eastern states of India

Objective: To detect the prevalence pattern of Chikungunya virus in three states of Northeast India. Methods: A total of 1 510 samples were collected from different private and government hospitals of Assam, Arunachal Pradesh and Meghalaya. Serum was tested for the presence of IgM antibodies against Chikungunya virus followed by RT-PCR for amplification of Chikungunya E1 gene region using specific primers. Results: Overall, 11.83% (172/1 454) clinical samples were positive by MAC-ELISA and/or RT-PCR assay. Asymptomatic infection was seen in 17.86%. Males were more affected than females and age group 16-30 years was mostly affected. Fever (100.00%) was the primary symptom followed by headache (72.03%) and arthralgia (41.53%). Only 118 Chikungunya positive cases could be traced, of which 25.42% complained about sequelae of infection. In entomological investigation, Aedes aegypti was more predominant (92.10%) than Aedes albopictus (7.90%). No mosquito pools could be incriminated for Chikungunya virus. Conclusions: In this study, Chikungunya was observed to be prevalent in Assam, Arunachal Pradesh and Meghalaya. Though Chikungunya is a self-limiting infection, increasing morbidity by CHIKV infection is affecting social and economic status of individual. Thus, a community empowerment to effectively control mosquito population by employing different mosquito control measures along with personal protection is mandatory to tackle future outbreak of the disease.