Abstract
Cystic echinococcosis (CE) is a parasitic zoonosis of public health importance caused by the larval stage of the cestode Echinococcus granulosus. CE has a worldwide distribution but exhibits the highest prevalence in communities where pastoral activities predominate, as the Mediterranean areas (Deplazes et al., 2017). The lifecycle of E. granulosus involves canids as definitive hosts and a broad spectrum of mammals, including humans, as intermediate hosts. A pivotal role in the transmission of echinococcosis is played by dogs (especially sheep dog and stray dogs of rural areas), due to their ability to wander freely in pastoral areas and prey on slaughtered livestock (Wang et al., 2022). In this context, the combined use of Geograpghical Information Systems (GIS) and innovative devices (e.g., GPS, drones), represent a useful tool for the development of innovative strategies to control CE. Recently, the delivery of baits containing praziquantel on the grazing areas using GPS and Unmanned Aerial Vehicles (UAV), proved to be an effective approach to treat stray dogs in areas endemic for alveolar echinococcosis caused by the larval stages of Echinococcus multilocularis (Yu et al., 2017).
The spatial analysis performed in this study aimed to design a new CE control strategy based on a thorough investigation of the micro-epidemiology of CE and the treatment of potentially infected definitive hosts, combining the use of GIS and innovative devices (GPS, drone, camera trap).
In 5 farms positive to CE, the movements of sheep and sheepdogs were tracked for 1 month, using 15 GPS devices applied to the animals. Multiple ring buffers and standard deviational ellipses were generated to estimate the size and the spatial distribution of the grazing areas. Punctual positions were fixed on the risk areas and medicated baits laced with Praziquantel were released by the UAV to deworm stray dogs.
Spatial patterns of the animal positions and the areas of the pastures with highest risk of access by potentially infected animals, were identified. A drone payload was designed on purpose for the release of medicated baits and spatial sampling criteria to improve deworming actions were introduced.
The study shows that the use of GPS collars is more effective than the traditional geospatial approach for accurate identification of the micro-epidemiological channels of the spread of CE, and allows to improve the rationalization of the resources needed to control CE infection. In addition, the results of the study confirmed that the combined use of geospatial technology and innovative devices might be a useful method to interrupt the Echinococcus lifecycle and to reduce the spread of the disease.
References
Deplazes, P., Rinaldi, L., Alvarez Rojas, C. A., Torgerson, P. R., Harandi, M. F., Romig, T., Antolova, D., Schurer, J. M., Lahmar, S., Cringoli, G., Magambo, J., Thompson, R. C., & Jenkins, E. J. (2017). Global Distribution of Alveolar and Cystic Echinococcosis. Advances in parasitology, 95, 315–493. https://doi-org.bibliosan.idm.oclc.org/10.1016/bs.apar.2016.11.001
Yu, Q., Xiao, N., Yang, S. J., & Han, S. (2017). Deworming of stray dogs and wild canines with praziquantel-laced baits delivered by an unmanned aerial vehicle in areas highly endemic for echinococcosis in China. Infectious diseases of poverty, 6(1), 117. https://doi-org.bibliosan.idm.oclc.org/10.1186/s40249-017-0329-8
Wang, L., Gongsang, Q., Pang, H., Qin, M., Wang, Y., Li, J., Frutos, R., & Gavotte, L. (2022). Assessment of echinococcosis control in Tibet Autonomous Region, China. Infectious diseases of poverty, 11(1), 59. https://doi-org.bibliosan.idm.oclc.org/10.1186/s40249-022-00987-9