A serological survey on Leptospiral infection in squirrels and hamsters in Ahvaz district, SouthWest of Iran

Leptospirosis is a zoonotic infectious disease of worldwide distribution. The infection is caused by various serovars of Leptospira interrogans sensu lato. Although the squirrels and hamsters are considered to be the reservoir or maintenance host of Leptospira, but little is known about the status of leptospirosis in these animals. This survey was conducted to evaluate the seroprevalence of Leptospiral infection in squirrels and hamsters in Ahvaz district, SouthWest of Iran. Blood samples were taken from 35 squirrels and 35 hamsters. Sera were screened for antibodies against serovars of L. canicola, L. icterohaemorrhagiae, L. grippotyphosa, L. ballum, L. hardjo, L. pomona, L. australis and L. tarassovi using the microscopic agglutination test (MAT). From a total of 35 squirrels, three cases (8.57%) were serologically positive for the serovars of L. grippotyphosa (2.86%), L. pomona (2.86%) and complex of L. hardjo + L. canicola + L. grippotyphosa + L. pomona (2.86%). Positive results were detectable at serum dilutions of 1:100 to 1:400. Seroprevalence did not show a significant difference for age and sex in the studied squirrel (p > 0.05). From a total of 35 hamsters, six cases (17.14%) were serologically positive. The predominant titers were directed against serovars of L. grippotyphosa (5.71%), L. grippotyphosa + L. pomona (2.86%), L. pomona (2.86%), L. icterohaemorrhagiae (2.86%) and L. canicola (2.86%). The positive results had 1:100 serum dilutions. Prevalence was significantly higher in adult hamsters above one year compared to hamsters less than one year (p < 0.05). The seroprevalence was more in male hamsters (23.53%) than females (11.11%), but the statistical analysis did not show a significant difference (p > 0.05). This survey indicated that serovars of L. grippotyphosa and L. pomona were predominant. The results provide useful information on the seroprevalence of leptospirosis in squirrels and hamsters of Ahvaz district.