Prevalence and Molecular Characterization of Cystic Echinococcosis in Livestock Population of the Malakand Division, Khyber Pakhtunkhwa, Pakistan

Abstract

Cystic echinococcosis (CE) is a neglected zoonotic disease prevalent in Pakistan, but the genetic diversity of the cestode is largely unexplored in the country. This study investigated the molecular epidemiology of CE infecting the livestock population of the Malakand division, Khyber Pakhtunkhwa, Pakistan. A total of 1,200 livestock, including buffaloes, cattle, goats, and sheep, were examined for echinococcosis from November 2017–2018 at different slaughterhouses in the Malakand division. Hydatid cysts were collected from different organs, and hydatid cyst fluid (HCF) was examined microscopically and used for DNA extraction. The LSU (rrnl) and NAD1 genes were amplified and sequenced. The overall prevalence of CE was 17% (204/1,200), including cows (21.7%), buffaloes (17.4%), goats (10%), and sheep (9.6%). The infection was relatively more prevalent among males (17%) than females (16.9%) and animals of older age (>5 years) (p = 0.710). Liver (63.2%) and lungs (25%) were more affected as compared to kidneys (6.8%) and heart (4.9%). HCF analysis indicated that 52.0% of the cysts were sterile and (48.0%) were fertile. Sequencing and phylogenetic analyses confirmed 80.0% of the isolates as Echinococcus granulosus sensu stricto (G1-G3) in all animal species, while Echinococcus equinus (G4) and Echinococcus ortleppi (G5) were present in buffaloes. The present study concluded that CE is prevalent in the livestock population of Malakand. Besides E. granulosus s. s. (G1-G3), E. ortleppi genotype (G5) and E. equinus (G4) in livestock were also reported.