In-House Developed ELISA Indicates High Prevalence of Anti- Echinococcus granulosus IgG in Sheep Population-An Update from Pakistan

Pathogens. 2020 Oct 29;9(11):905. doi: 10.3390/pathogens9110905.

Abstract

Cystic echinococcosis (CE) is a World Health Organization (WHO)-listed neglected tropical farm economy jeopardizing and public health concern disease. This study was aimed at furnishing sero-epidemiological baseline data of CE in sheep in Pakistan, where data are non-existent. For this purpose, two sheep-rich provinces of Pakistan were selected, and 728 sheep sera were collected using probability proportional to size (PPS) statistical technique. Epidemiological information was recorded on a questionnaire for the estimation of potential risk factors. The serum samples were analyzed for IgG antibodies against Echinococcus granulosus using an in-house-developed EgAgB-based ELISA kit. The overall seroprevalence recorded was 21.98% (160/728) in the tested sheep, suggesting higher seropositivity in sheep from Punjab (23.73%) as compared to Khyber Pakhtunkhwa (KPK) (19.04%). The overall apparent prevalence observed by this ELISA method was almost similar to the calculated true prevalence (21.77%). Prevalence was significantly different (p < 0.05) among sheep from different districts. Higher prevalence was found in females (22.54%, OR 1.41), age group > 5 years (29.66%, OR 1.64), crossbreeds (42.85%, OR 2.70), and sheep with pasture access (25.96%, OR 3.06). Being in age group > 5 years and having pasture access were the factors significantly associated with seropositivity (p < 0.05). This study provides serological evidence of E. granulosus infection in sheep and can be used as a model for ante-mortem screening of the sheep globally.

Keywords: ELISA; Echinococcus granulosus; Pakistan; epidemiology; risk factor; seroprevalence; sheep.