Biology and Hosts of Echinococcus Species in China

Echinococcosis, is a serious zoonotic disease with severe prevalence in the vast western and northwestern pastoral areas of China, one of the highest prevalence rates in the world. Cystic echinococcosis (CE) and alveolar echinococcosis (AE), are endemic in some areas simultaneously, posing a serious threat to the health and socio-economic development of local populations. Echinococcus species (spp.) can infect both domestic and wild animals through the domestic cycle, wild cycle and mixed domestic–wild cycle, completing the cycle chain. In the pastoral areas of western China, the extensive distribution of pasture and forest and the abundance of domestic and wildlife resources provide a good environment for the growth and egg success of Echinococcus spp. This, together with the unique human factors in endemic areas, poses a great challenge to the prevention and control of Echinococcus spp. nowadays, resulting in a large number of population infections in the West in recent years, especially in the Qinghai-Tibet Plateau and Yili, Xinjiang. Based on previous epidemiological studies, this chapter reviews the important factors contributing to the spread of Echinococcus in China, focusing on three aspects: biological (parasite genotype and host species), environmental (landscape and climate) and social (age, sex, ethnicity, education, occupation, lifestyle, cultural practices, living conditions and hygiene habits of populations in endemic areas), which interact with each other to determine the transmission of Echinococcus tapeworm. In view of the current epidemiological situation of echinococcosis in China, and in view of the above-mentioned challenges in the prevention and control of echinococcosis, in order to implement precise prevention and control, and to achieve a shift from the previous ‘crude’ prevention and control to ‘precise’ prevention and control, it is more important to highlight science and precision, and it is urgent to use scientific theories and methods to grasp the many epidemiological factors of echinococcosis, to accurately identify and assess the future risk of echinococcosis transmission and its changing trends, and then to identify potential high-risk areas and develop efficient control strategies.