Seroprevalence of Chikungunya Virus Infection in Sistan and Baluchestan Province, Iran: A Pilot Study

Background: Chikungunya virus (CHIKV) spreads by Aedes mosquitoes in tropical and subtropical regions. Due to the geographical and social situation of the border cities of Sistan and Baluchestan province, this study was conducted to evaluate the prevalence of the Chikungunya infection in the southeastern cities of Iran using enzyme-linked immunosorbent assay (ELISA). Methods: In this cross-sectional study, 203 participants were randomly selected from 4 southeastern cities of Iran (Taftan, Sib-and-Suran, Mehrestan, and Mirjaveh). First, sociodemographic and clinical data were gathered by a questionnaire. Next, individual blood samples were taken, and ELISA was performed to measure anti-CHIKV IgG levels. Results: The participants’ ages ranged from 6 - 50 years, with 27.5% of them being 21 - 30 years old. Based on the results, 17 cases (8.37%) had episodes of fever, 13 (6.40%) had fever and arthralgia, and 12 (5.91%) had a history of hospitalization. In addition, there were 3 positive samples (1.48%). One of these people lived in Mehrestan, and two lived in Sib-and-Suran. The incidence of the virus infection was significantly higher in the age groups of 41 - 50 and 21 - 30 years old (P = 0.046). The likelihood of CHIKV infection was higher in farmers, independent contractors, and housewives (P = 0.001). Moreover, the most indicative clinical symptoms were the simultaneous occurrence of fever and arthralgia. Conclusions: The findings of this study confirm the presence of CHIKV in Sistan and Baluchestan. The geographic distribution of the positive samples indicates that other factors are involved in the spread of infection besides the tropical climate and proximity to Pakistan.