Prevalence of Linguatula serrata infection among dogs (definitive host) and domestic ruminants (intermediate host) in the North West of Iran

Linguatula serrata is a zoonotic parasite causing visceral and nasopharyngeal linguatulosis in humans. Dog and other canines are the main definitive hosts while most herbivores, including ruminants serve as intermediate hosts for linguatulosis. Human rarely become infected as both final and intermediate hosts. This survey aimed to assess the L. serrata infection rate of dogs and domestic ruminants in North West of Iran. The upper respiratory tract of 97 dogs including 45 females and 52 males and the mesenteric lymph nodes (MLNs) of 396 goats (203 females and 193 males), 406 buffaloes (166 females and 240 males), 421 cattle (209 females and 212 males) and 438 sheep (223 females and 215 males) were examined for L. serrata. Animals were categorized into four age groups, including under six months, six to 24 months, two to four years and more than four years. Results showed that 27.83% of dogs were infected with L .serrata. The infection rate for goats, buffaloes, cattle and sheep was 50.75%, 26.6%, 36.62% and 42.69%, respectively. The prevalence rate in all animals was significantly associated with age and sex (P ≤ 0.05). In ruminants, the highest infection rate was found in goats (P ≤ 0.05). The results from this study indicate a high rate of infection in dogs and domestic ruminants, suggesting a potential high risk of zoonotic infection in man in the investigated area.