Surveillance, prevention and control of echinococcosis

The disease can be prevented by periodic deworming of dogs, improved hygiene in the slaughtering of livestock including proper destruction of infected offal, and public education campaigns. Vaccination of livestock with an E. granulosus recombinant antigen (EG95) offers encouraging prospects for prevention and control. Small-scale EG95 vaccine trials in sheep indicate high efficacy and safety with vaccinated lambs not becoming infected with E. granulosus. A programme combining vaccination of lambs, deworming of dogs and culling of older sheep could lead to elimination of human cystic echinococcosis in less than 10 years.

Taking sheep for disease testing, Ethiopia ©ILRI / Barbara Wieland

Prevention and control of alveolar echinococcosis is particularly complex as the cycle involves wild animal species as both definitive and intermediate hosts. Regular deworming of domestic carnivores that have access to wild rodents should help to reduce the risk of infection to humans. Culling of foxes and unowned free-roaming dogs is applicable but appears to be highly inefficient. Deworming of wild and stray definitive hosts with anthelminthic baits resulted in significant reductions in the prevalence of alveolar echinococcosis in European and Japanese studies. Sustainability and cost–benefit effectiveness of such campaigns are however controversial.

Surveillance of cystic echinococcosis in animals is difficult because the infection is asymptomatic in livestock and dogs, and is not recognized or prioritized by communities or local veterinary services. However, inspection of carcases after slaughter can be used to deliver information. For alveolar echinococcosis, surveillance is rarer still due to the involvement of wildlife in all parts of the cycle. Existing data are scattered and derived from infrequent surveys rather than regular national surveillance in most parts of the world.