Influence of Ionizing Irradiation on Infectivity of Eggs of Echinococcus granulosus in Laboratory Rodents

Effects of gamma irradiation on the infectivity and development ofHymenolepis nana oncospheres (Cestoda: Cyclophyllidea)

“…X-irradiation of Echinococcus granulosus cysts at 20000 r and 30000 r had inhibitory effects on the subsequent growth of worms in dogs (Movsesijan et al, 1968) and similar irradiation of the eggs of this parasite reduced infectivity for rodents (Williams and Colli, 1972). Dow et al (1962) protected mice against, challenge with eggs of Hydatigera taeniae/ormis by vaccinating them orally with eggs attenuated through X-irradiation at 40000 to 100000 r. The immunizing parasites did not develop into liver eysticerei.…”

Inhibitory effect of different UV lamps on the infectivity of taeniid eggs

“…However, it was observed that the survival of taeniid eggs is greatly aected by desiccation (Laws 1968). Relative resistance of taeniid eggs to chemicals was observed (Veit et al 1995) and a remarkable resistance to UV radiation in Echinococcus granulosus eggs was also reported (Williams and Colli 1972). Recently, in a preliminary report, Konno et al (1997) showed that UV radiation at 254 nm for a total exposure dose of more than 2,880 mJ/cm 2 completely inhibited the infectivity of Taenia taeniaeformis eggs.…”

Echinococcus spp.

“…For inactivation of taeniid eggs irradiation doses higher than 40 krad are apparently required: after infection of laboratory rodents with eggs of Taenia taeniaeformis irradiated at 60 krad metacestodes did not develop (Dow et al, 1962).The infectivity of E. granulosus eggs after irradiation with doses of 10, 20 and 30 krad (= 100, 200 and 300 Gray) was diminished, but not lost (Williams and Colli, 1972). Echinococcus multilocularis eggs irradiated with a dose of 40 krad triggered specific antibody production but metacestodes did not develop (Veit et al, 1995).…”