Lyme disease : the foxes to the rescue

MennoSchaefer/epictura

Published the 03.08.2017 at 16h04

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Keywords :

Lymetiqueprévention

Lyme disease progresses. The reading of the figures of contamination, probably largely under-estimated, it becomes a public health problem. The health agencies are trying to respond to this bacterial infection not always obvious to heal, now having in mind that for preventing its diffusion, it is necessary to do the prevention, and of interest to the ticks.

By their sting, these arachnids are the vector of the bacterium designated as responsible for the disease, Borrelia burgdorferi, as well as other as yet poorly identified. And their population is increasing in our forests. But these ticks could have found their enemy : the fox.

Human Intervention

More specifically, the animal would reduce the number of infected ticks. Dutch researchers have shown that more foxes are numerous in the forests, less ticks are carriers of the bacteria ; and vice versa. The decrease is not negligible : in the most populated areas in foxes, infected ticks collected on rodents can be up to 20 times less numerous.

These results were obtained by comparing the infection rates of ticks in twenty forests of the netherlands. Some of the reserves were natural, with populations of foxes important. For others, the canines were removed either unintentionally, when woods have been fragmented by human activities, either voluntarily, and there are now virtually non-existent.

This is not the first time that this correlation is observed, but in an article published in the journal Proceedings of the Royal Society, scientists explain its mechanism.

The fox’s away, the mice will play with the ticks

To get to a reproductive stage, the tick must conduct three blood meals, which enable him in particular to develop from a larva stage to the pupa, and then to his adult form. In the forest, the larvae, in principle, devoid of any infection, cling to the first animal come to that, in these ecosystems, are often of small mammals : voles, mice, or other rodents.

However, these species are often carriers of many pathogens, including Borrelia. After the bite, the ticks are infected, and may, in turn, ltransmettre the bacteria to other animals, and in particular to man.

But when the foxes prowl, rodents are more discrete, and arachnids are somewhat lacking. They do people with no victim, or fall back on other species, sometimes on birds. Of the species less – or not at all – carrying the bacteria. Thus, mechanically, the rate of infected ticks down.