Cystic Echinococcosis in Iceland: a Brief History and Genetic Analysis of a 46-year-old Isolate Collected Prior to the Eradication of This Zoonotic Disease

Overview

Journal Parasitology

Specialty Parasitology

Date 2023 May 10

PMID 37161714

Authors

Urmas Saarma

Karl Skirnisson

Thorunn Soley Bjornsdottir

Teivi Laurimae

Liina Kinkar

Affiliations

Soon will be listed here.

Abstract

Cystic echinococcosis (CE) is considered the most severe parasitic disease that ever affected the human population in Iceland. Before the start of eradication campaign in the 1860s, Iceland was a country with very high prevalence of human CE, with approximately every fifth person infected. Eradication of CE from Iceland by 1979 was a huge success story and served as a leading example for other countries on how to combat such a severe One Health problem. However, there is no genetic information on parasites before eradication. Here, we reveal the genetic identity for one of the last isolates in Iceland, obtained from a sheep 46 years ago (1977). We sequenced a large portion of the mitochondrial genome (8141 bp) and identified the isolate as genotype G1. As G1 is known to be highly infective genotype to humans, it may partly explain why such a large proportion of human population in Iceland was infected at a time . The study demonstrates that decades-old samples hold significant potential to uncover genetic identities of parasites in the past.

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