Basel residents criticise late warning over Legionella outbreak

Residents of Basel’s Kleinbasel neighbourhood have criticised the authorities for informing them about a Legionella outbreak two weeks after an unusual rise in illnesses was detected, SRF reported. One person has died and 26 people have been infected.

The suspected source is a cooling system on the roof of a Manor office building. The system’s two wet cooling towers have been switched off.

Marco Natoli, who lives opposite the building, said he was contacted by friends on WhatsApp asking whether he was well. “It gives you an uneasy feeling when you come home,” he said.

Natoli said the authorities should have contacted local residents directly. A leaflet delivered to homes or a hotline for concerned neighbours would have helped, he said. He knows someone who had to be treated in intensive care because of the outbreak.

Other residents also said they felt poorly informed. Some older people in the neighbourhood were particularly unsettled, one passer-by said. A bookshop in Rebgasse and a Reformed church congregation had not yet heard about the outbreak the day after the authorities’ announcement.

Eva Würfel, deputy cantonal physician at Basel-Stadt’s health department, said the authorities took the concerns seriously. They had deliberately sought to reach not only residents but also people who might have visited the neighbourhood, she said, using a news conference and social media.

Several patients have since left hospital, Würfel said. Only a few remain in hospital, with one person still in intensive care. No further Legionella infections had been reported by Tuesday noon.

The cantonal laboratory is examining the homes of all 26 infected people. Cantonal chemist Yves Parrat said officials would continue looking for other possible sources in the city until they had definitive proof that none existed. Genetic tests are also being carried out to compare bacteria from the cooling system with those found in patients.

People becoming infected in public spaces through vapour from a cooling system is uncommon, according to SRF science editor Christian von Burg, although similar cases have occurred in Germany. Switzerland has thousands of comparable systems, so the possibility of Legionella spreading through the air elsewhere cannot be ruled out.

Manor did not comment on residents’ criticism of the information provided. The company said the cooling towers had been shut down and that specialists were examining the system. Three Manor employees have also been infected, but the company said their illnesses had not been confirmed as connected to the outbreak.