Climate change increasing the prevalence of harmful parasite, warn scientists

Credit: CC0 Public Domain

A rise in a parasite called liver fluke, which can significantly impact livestock production in farms in the UK and across the world, could now be helped by a new predictive model of the disease aimed at farmers. The tool, developed by University of Bristol scientists, aims to help reduce prevalence of the disease.

Cattle or sheep grazing on pastures where the parasite is present can become infected with , which develops in the liver of infected animals, leading to a disease called fascioliasis. Current estimates suggest liver fluke contributes to around £300 million annually in lost productivity across UK farms and $3 billion globally.

Until now, risk predictions have been based on rainfall estimates and temperature, without considering the life-cycle of the parasite and how it is controlled by levels of . This, combined with shifts in disease timing and distribution attributed to climate change, has made liver fluke control increasingly challenging.

A new tool for farmers has now been developed by the Bristol team to help them mitigate the risk to their livestock. The model, which works by explicitly linking liver fluke prevalence with key environmental drivers, especially soil moisture, will help farmers decide whether they avoid grazing livestock on certain pastures where liver fluke is more prevalent, or treat animals based on when risk of infection will be at its peak. Importantly, the model can be used to assess the impact of potential future climate conditions on infection levels and guide interventions to reduce future disease risk.

Ludovica Beltrame, one of the study's researchers from Bristol's School of Civil, Aerospace and Mechanical Engineering, said: "In recent decades, the prevalence of liver fluke has increased from 48 to 72 per cent in UK dairy herds. This new tool will help farmers in managing the risk associated with fluke and offers a more robust approach to modelling future climate change impacts."

Professor Thorsten Wagener from Bristol's Cabot Institute added: "Water-related diseases can be difficult to eradicate using medicine alone, as resistance to available drugs is increasing. We need predictive models of disease risk that quantify how strongly infection risk is controlled by our rapidly changing environment to develop alternative intervention strategies."

Explore further

Global health lessons from Thailand's successful liver fluke elimination campaign

More information: Ludovica Beltrame et al. A mechanistic hydro-epidemiological model of liver fluke risk, Journal of The Royal Society Interface (2018). DOI: 10.1098/rsif.2018.0072
Citation: Climate change increasing the prevalence of harmful parasite, warn scientists (2018, August 29) retrieved 19 June 2019 from
This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only.

Feedback to editors

User comments

Aug 29, 2018
This comment has been removed by a moderator.

Aug 29, 2018
Who knows? Americans are being infected by many diseases that were mostly eradicated here in the States, but are now making a comeback in the bodies of the illegals from Mexico and Central America - and elsewhere who are sneaking in for the free goodies. And about half of all Americans don't seem to have a problem that other Americans are being infected (some have died) from some exotic diseases like Zika.
It is possible that those Americans are just too ignorant to care, unless, of course, they are the ones to come down with those diseases. Only then they might come to their senses and demand that the illegals be kept out of American cities or countryside by the US government.
But there is no accounting for the origins of stupidity in the first place.

Aug 29, 2018
But WHY did physorg use a photo of a cloudy night sky instead of a photo of a "liver fluke" so that we can see what it looks like, as far as liver flukes go? Are there liver flukes flying about up there?
Did the photo of a liver fluke get lost in the shuffle? Tossed into the trash? Used to wrap a sandwich or something from the fish market? It makes no sense. How are we supposed to fight the enemy when we can't even see it?

Ok, time for Wikipedia, I suppose.

Aug 30, 2018
Cold kills 1.5 million people a year.

Aug 30, 2018
Two days ago you said cold kills 1.4 million people a year. Did 100,000 people die of cold in the last two days? 'Cause it looks like you are actually just lying and forgetting that you told a slightly different version of the lie already.

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more