Background: Brucellosis is endemic in Iran with a higher level of endemicity in western areas, including the Hamadan province. This study aims to define the seroprevalence of brucellosis and it,s risk factors in general the population of Famenin, Hamadan province, in western Iran.

Methods: This survey was conducted on 2367 participants in Famenin and its villages from September to November 2016. After receiving written consent from subjects, demographic information was obtained through questionnaires and 10cc blood samples were taken from the participants. Blood samples were sent to the Core facility of Hamadan University of Medical Sciences and were tested using Wright and 2ME kits (Pasteur Institute, Iran) for serological detection of brucellosis. The seroprevalence of brucellosis was reported as percentage with 95% confidence interval (CI).

Results: Totally, 2367 individuals with the mean age (SD) of 34.6 (20.9) (range: 2 to 95) years were enrolled. Of these, 1060 (44.8%) were men and 1610 (68.0%) lived in rural areas. The seroprevalence of brucellosis according to the Wright titer (equal to or greater than 1:80) was 6.6% (95% CI: 5.62%, 7.66%). The corresponding prevalence based on 2ME titers (equal to or greater than 1:40) in subjects with positive Wright test was 37.2% (95% CI: 29.5%, 44.84%). We saw a significant association between the incidence of brucellosis and occupation (P < 0.001) and type of contact with livestock (P = 0.009) as two important risk factors.

Conclusion: The seroprevalence of brucellosis in Famenin population was considerable. Contact with livestock, animal husbandry, farming and history of brucellosis were risk factors for brucellosis infection.