Viability of Echinococcus granulosus protoscolices at different conditions.

The aim of this study was to examine the longest survival time of Echinococcus granulosus protoscolices stored at different humidities and constant temperatures from -10 to +40 degrees C. Sheep livers containing hydatid cysts obtained from slaughterhouses were taken to the laboratory within 3h and transferred into incubation cabinet previously set at -10, 0, +10, +20, +30 and +40 degrees C with different relative humidity (RH). Viability of protoscolices was assessed by 0.1% eosin staining. The longest survival times were 3 days at -10 degrees C (50% RH), 36 days at 0 degrees C (60% RH), 28 days at 10 degrees C (65% RH), 12 days at 20 degrees C (70% RH), 4 days at 30 degrees C (75% RH) and 3 days at 40 degrees C (80% RH).