Prevalence and morphopathological characteristics of linguatulosis in one-humped camel (Camelus dromedarius) in Yazd, Iran.

Linguatula serrata is a cosmopolitan zoonotic parasite. Its adult form inhabit the nasal and respiratory passages of canids as the definitive hosts while its immature stages localize in the mesenteric lymph nodes or in other organs of herbivorous intermediate hosts. We examined the liver, mesenteric, and mediastinal lymph nodes of 272 camels slaughtered at the slaughterhouse of Yazd, Iran. Forty-one out of 272 camels (15.1 %) were infected with nymphs of L. serrata. Twenty-four out of 166 males (14.45 %) and 17 out of 106 females (16 %) were positive. The livers of five camels, which also had nymphs in their lymph nodes, were infected with the larval stage of this parasite. The infection rate increased with age and was highly significant, while sex did not play a significant role in the prevalence of this parasitic infection. The infected lymph nodes were grossly enlarged, edematous, and consisted of hemorrhagic and necrotic lesions. Histopathologically, the architecture of the infected lymph nodes was degraded, necrotic, and sectioned migrating stages of L. serrata were clearly visible. In some lymph nodes, parasitic granulomatous lymphadenitis with necrosis and in some cases, degenerated parasite in central area was observed. High prevalence of infection in camels suggests possibility of similar high rate of infection in other animals of this region. In view of the consumption of raw or undercooked visceral organs of camel by humans of this region, the importance of careful inspection at slaughterhouse needs to be emphasized.