Of the 3,400 ticks sent to the public health institute RIVM for testing last year, 22% were found to be infected with the bacteria which gives rise to Lyme disease.

But just 3% of 7,000 people who reported having been bitten by a tick went on to develop the disease, the RIVM said. Left untreated, Lyme can affect the joints, heart and central nervous system.

The RIVM and Wageningen University set up the special monitor last year in an effort to better understand the Dutch tick population. People living in Drenthe are the most likely to be bitten by ticks, followed by Groningen, Utrecht and Gelderland. 

In order to avoid being bitten, the RIVM recommends people check their skin and clothing well if they have been in the countryside. People are also advised to wear long sleeves and tuck their trousers into their socks.