MONTREAL – Bacteria and yeast: that’s what was found on the handrails in the Montreal Metro, according to a molecular biologist who conducted tests for La Presse.

Sylvain Beausoleil, a microbiology teacher at Ahuntsic College, went into the Metro on Oct. 7. According to the news report, he found so much bacteria that it was impossible to count under a microscope.

The scientist also found traces of pathogens that could lead to different skin diseases, including numerous fungal infections.

The Société de transport de Montréal (STM) tells CTV News it’s normal for bacteria to be found on the metro due to the large number of people travelling every day – about one million trips.

However, the public transit authority admits it only does a full clean of the underground network every five to six weeks.

“Our main constraint is that if we were to stop the trains [to clean them every day], it would affect the quality of service,” STM spokesperson Philippe Déry said.

He notes that the public transit authority doesn’t do regular testing, and only calls on outside experts if there is a public health issue.

Nevertheless, the STM insists it aims to have all “visible areas” of the metro stations, including the ticket machines, washed at least once a week.

“A partial interior washing of the Metro car floors is carried out approximately every three days for the entire fleet,” Déry said, adding some of the products are organic and hospital-grade.

“Some of these products even have a residual effect of up to 24 hours.”

He adds that in “customer-related incidents, such as vomit,” workers use specific disinfectants.

Déry reminds the public that the usual health tips apply to anyone using public transit: wash your hands and sneeze or cough into your elbow to prevent the spread of any bacteria.