Nieuws - 3 april 2008

Risky ticks in Ede woods

Whereabouts in the Netherlands you get bitten by a tick can make a difference. The chance of developing Lyme disease is greatest if it’s a tick from the woods in Ede starts sucking your blood. according to a Wageningen study. Researchers from Plant Research International and the Entomology group have determined the bacteria population of Dutch ticks.

‘When ticks bite they can transfer Borrelia bacteria which cause Lyme disease,’ says Dr Leo van Overbeek. ‘We don’t know for sure where the bacteria come from. But ticks probably pick them up when they suck the blood of small mammals or birds, which are a reservoir of Borrelia in the wild.’

Van Overbeek and his colleagues used molecular techniques to examine the bacteria in ticks from woods near Amsterdam, Veldhoven in the south and Ede. First they determined what strains of Borrelia bacteria were present. The ticks from Ede had the highest numbers of Borrelia bacteria. However, the bacteria are so widespread that the differences between the ticks were not statistically significant.

When they screened the whole bacteria population in the ticks, the researchers found even more potential pathogens. Ticks from near Amsterdam had more Rickettsia australis, a pathogen that can cause high fever. Another risky bacteria found in the ticks from Ede was Neoehrlichia mikurensis, a pathogen that was only discovered a few years ago and about which little is yet known.

‘What is striking is that the bacteria population in the ticks varies so much depending on which woods they come from,’ says Van Overbeek. ‘Perhaps it’s because different kinds of animals live in different woods, as a result of which the bacteria population in ticks varies.’ According to Van Overbeek this could open up possibilities. ‘Maybe there are ‘friendly’ bacteria that can fight the Borrelia bacteria, like beneficial bacteria in healthy desserts can reduce harmful bacteria in the human gut. If we find the right bacteria maybe we can introduce measures that will make the woods in Holland safer.’