Seasonal attempt to bring Brussels' rat numbers down

Brussels has twice as many rats as people - and a big autumn operation to reduce their numbers is now under way.

Water firm Vivaqua spends €200,000 a year on pest control in the city's sewer system. Twice a year, in teams of two, workers go from manhole to manhole around all of Brussels' 19 communes, placing small blocks of poison at the end of a wire.

The strength of the poison depends on how well previous pest control operations went, taking into account any complaints from locals.

It is estimated that there are up to 2.5 million brown rats in the Brussels region. Vivaqua's Pierre Henrion told RTBF: "If we did nothing, we could be invaded by rats."

As well as being a health issue, rats also damage pipes. "Old brick buildings make a playground for them," Henrion added.

This latest campaign aims to bring rat numbers down - not eradicate them entirely. "Rats still play a useful role in the environment," said Yves Laurent of Belgium's Institute of Natural Sciences. "They are excellent waste managers. They feed on about a third of the waste that people throw away."