Prevalence and risk factors of canine dirofilariasis in Kano metropolis, Kano State Nigeria

Abstract

Dirofilariasis is a zoonotic disease caused by Dirofilaria immitis causes heartworm disease and invasive human filariasis. This study  determined the prevalence and risk factors for the acquisition of canine dirofilariasis in dogs in Kano metropolis, Kano state, Nigeria.  Blood samples were collected from 170 dogs of 6 months and above in Kano metropolis and tested by the Modified Knott’s technique for  circulating microfilaria, an Enzyme-linked Immunosorbent Assay in order to detect the presence of filarial antigens of D. immitis as  evidence of occult infection. A pre-tested, structured questionnaire was administered to each of the dog owner to obtain demographic,  management and environmental information associated with each dog sampled. Test for association and hypothesized factors was  determined and the its strength was tested using a binary logistic regression. Out of the 170 dogs tested, 17 (10.00%) were positive for D.  immitis infection with the Modified Knott’s technique. However, after subjecting the samples for antigen detection by ELISA tests 23  (13.53%) were positive for D. immitis antigen, giving a sero-prevalence of 13.50%. There was agreement between the two tests on the 17  microfilaria positive samples. Majority of the infected dogs were males (56.5%), aged 24-47 months (43.50%) and of local breed (65.2%).  There was significant association (p ≤ 0.05) between D. immitis infection and dogs usage, breed and dogs with stagnant water (gutters)  close to their houses (OR= (9.714; 95% CI (1.179-80.024)), OR=5.33; 95% CI (1.349-21.079), OR= 5.775; 95% CI (0.697- 47.832),respectively.  The study established that D. immitis infection is prevalent (13.53%) in household dogs indicating the possibility of zoonotic transmission  in Kano metropolis. This demands for intensified vector control and good dog management practices to reduce dog to dog and dog to   human transmission.