Laetitia Lempereur
Parasite Resistance Specialist, Food and Agriculture Organization of the United Nations (FAO)
Parasitic diseases are caused by infectious agents, which maintain a parasitic relationship in which ‘one organism benefits at the expense of the other.’
Parasitic diseases include a broad spectrum of agents, such as worms (eg. ascaris), protozoans (eg. malaria, babesia) and arthropods (eg. mosquitoes, ticks). They directly cause diseases in a host or act as vectors of various pathogens, causing huge impacts across the entire One Health spectrum.
Parasitic diseases harm food production and immunity
Around 70% of production animals are estimated to experience severe parasite transmission. This is a very common challenge that farmers are facing worldwide, with important economic impacts and potential public health concerns. While addressing issues of worms, ticks, mosquitos and protozoans may seem disparate from antimicrobial resistance challenges, they are more interconnected than one might think.
The consequences of these parasitic diseases range from mortality to production losses such as reduced milk and meat production. It also impacts the host’s immune system, potentially reducing vaccine efficacy and increasing susceptibility to co-infection, which may necessitate additional drugs such as antibiotics.
Why vector and parasite control is essential
Control of parasitic diseases and vectors is mainly achieved by synthetic medicinal products. These are products composed of a wide range of drug classes and molecules, which represent the second largest global market segment in the animal health industry after vaccines. Some of these antiparasitic drugs are classified as antimicrobials. Alongside this, the direct indication of antibiotic use as antiparasitic treatment is often under-recognised.
However, many of these parasites are transmitted by vectors such as mosquitoes, ticks or flies. It is therefore clear that, in addition to the antimicrobial drugs used directly against these parasites, vector control is a key component to combating these diseases, as well as other vector-borne diseases. Vector control primarily relies on insecticides or acaricides, some of which also target other parasites like worms.
The direct indication of antibiotic
use as antiparasitic treatment
is often under-recognised.
Drug overuse fuels resistance
Overuse, misuse and use of substandard medicinal products are the main factors contributing to antimicrobial resistance as well as antiparasitic drug resistance. The rapid emergence and spread of drug-resistant parasite strains — such as ticks, mosquitoes and worms — are alarming.
Failure to include vector control and antiparasitic drug resistance in the animal health priorities and AMR fight will hinder productivity, increase the burden of diseases and reduce the effectiveness of preventive vaccination measures. This also contributes to AMR.
Parasitic control reduces antimicrobial reliance
In the FAO’s 10-year RENOFARM initiative, the control and prevention of parasitic diseases will play a crucial role in reducing the need for antimicrobials on farm level. During AMR Awareness Week, it’s important to remember that, like antibiotics, resistance to antiparasitic drugs is a global issue that impacts the entire One Health spectrum and requires a comprehensive approach.
