Incidence of Cystic Echinococcosis in Libya: I. Seroprevalence of Hydatid Disease in Sheep and Goats Naturally Exposed to the Infection in the North Midland Region

Hydatid disease is one of the most and serious public health and veterinary problems in Libya and other North African countries. Thirteen rural villages of two main districts bordered to each other at the north midland of the country namely, Misrata which is almost agricultural area and about 200 km east of Tripoli and Sirt which is almost pasture area and about 500 km east of Tripoli, were included in the current study. Incidence of cystic echinococcosis was investigated serologically using serum samples collected from 2651 animals of three groups; young sheep under two years old (240), adult sheep over two years old (2082) and adult goats over two years old (329). Antigen B prepared from camel crude hydatid cyst fluid together with ELISA were used for detection of total IgG antibodies against hydatid cysts in the collected serum samples. 1377/2651 serum samples from all animal groups of both districts gave overall ELISA seropositive result of 52%. The overall ELISA seropositivity for each group of animals was 55/240 (23%), 1235/2082 (59%) and 87/329 (26%) for young sheep, adult sheep and goats (all adults) respectively. In Misrata district, the overall seropositivity was 729/1243 (59%) and among the villages it was 43% from Saso and 78% from Tawergha; while in Sirt district, the overall seropositivity was 648/1408 (46%) and among the villages it was 25% from El-Gbeba and 63% from El-Arbaien. Statistical analysis showed no significant differences in the rate of seropositivity between the three groups of animals which was 23, 59 and 26%, in young sheep, adult sheep and adult goats respectively and between the two district areas which was 59% in Misrata and 46% in Sirt. Also statistical analysis showed no significant differences in the rate of seropositivity between the different age animal groups which was 23% for young sheep and 68% for adult sheep 7- <10 yrs old and in the case of goats, it was 24% for goats 2- <4 yrs old to 29% for goats 7+ yrs old.