A year after CBC's Marketplace revealed shocking issues with cleanliness in Canadian hotels, follow-up testing reveals that lack of proper sanitizing is still a problem in top chains.

Marketplace this week See how you can protect yourself from hotel germs when you travel. Watch Marketplace's episode, The Dirt on Hotels: We’re Back Friday at 8 p.m. (8:30 p.m. in N.L.).

Marketplace retested six of Canada’s biggest hotel chains and found that despite some progress, some chains actually performed worse than last year.

“Certain hotels have actually gone backwards. They've actually gotten worse,” microbiologist Keith Warriner told Marketplace co-host Erica Johnson.

The full investigation, The Dirt on Hotels: We’re Back, which also ranks hotels based on their performance and their improvement from last year, airs Friday at 8 p.m. (8:30 p.m. NT).

Some of the problems that Marketplace found in this year’s test included unclean bedding and surfaces that hadn’t been properly cleaned or sanitized. In one case, a stain found last year on the wall of a room at the EconoLodge in downtown Toronto -- which Warriner says was likely urine -- was still there.

Checking back in

Last year, Marketplace tested 54 hotel rooms in Vancouver, Montreal and Toronto across six of Canada’s biggest hotel chains. The hotels tested included budget options such as the Super 8 and EconoLodge, mid-range hotels the Holiday Inn and Best Western, as well as higher-end rooms in the Sheraton and Fairmont.

For this year’s investigation, Marketplace retested rooms in the same hotel chains in Toronto, testing three rooms per hotel.

Microbiologist Keith Warriner assisted Marketplace in its investigation of the cleanliness of hotels. (CBC)

Under the guidance of Warriner, a professor at the University of Guelph and one of Canada’s leading microbiologists, Marketplace tested the hotel rooms both for general cleanliness and for a variety of germs that can’t be detected by the naked eye.

The tests included visual inspection with a black light; microbiological testing for germs including bacteria, coliforms -- which could indicate fecal contamination -- and antibiotic-resistant superbugs. There was also a hidden camera test to document housekeeping practices. Marketplace also took samples from ice machines and tested the ice for coliforms.

Lack of proper cleaning could pose a serious risk to travellers, says Warriner, because people have no way of knowing if previous guests were sick, and because of the high volume of people who stay in hotels, that exposure can be even greater.

Marketplace focused on surfaces in hotel rooms that guests frequently touch, such as remote controls, telephones, faucet handles and lamps.

Ice machines cleaner, but superbugs still a problem

This year’s testing indicates that hotels taken some positive steps in their cleaning practices, while other problems remain.

In last year’s investigation, ice machines in all six hotel chains were found to contain coliforms, a possible sign of fecal contamination. In one instance -- an ice machine at the Sheraton Centre hotel in Toronto -- the tests found a strain of E. coli.

This year’s testing, however, found clean ice in every hotel tested.

“I think it's very good what they're doing, I think it's very positive that they're taking steps,” says Warriner.

Air vents -- a site of visible mold growth in last year’s tests -- also appeared to be cleaner.

However, results from microbiological testing found superbugs at all chains except one, Super 8.

MRSA, which is an antibiotic-resistant strain of Staphylococcus bacteria, was found on a variety of frequently touched surfaces in hotels, including a TV remote, bathroom counter and lamp.

The Marketplace testing also found C. difficile, which can cause serious illness in some people, on a toilet seat at the Sheraton Centre hotel in Toronto. While MRSA and C. difficile may not be an immediate threat to healthy individuals, they can pose problems for those who are sick or have compromised immune systems.

According to Warriner, the results indicate that hotels are not properly sanitizing rooms. “In hotels, we don't know who's been in there before,” Warriner says. It’s a concern, he says, that combined with the lack of sanitizing could easily lead to the spread of illnesses such as flu or norovirus.

Despite hard work, housekeepers’ equipment lacking

This year’s examination suggested that while housekeepers were often diligent, test results at some hotels revealed widespread cross-contamination in some hotel rooms.

“What the study's really showing is that they're not sanitizing the room. They're cross-contaminating rooms,” says Warriner.

One of the causes of the cross-contamination, according to Warriner, may be lack of proper equipment, and insufficient use of sanitizer.

In some hotels, hidden camera testing revealed that the cleaning caddies provided to housekeepers may allow sponges, cloths and toilet brushes to come into contact with one another, allowing cross-contamination.

The Hotel Association of Canada, which describes itself as the “voice of the Canadian Hotel & Lodging industry” declined to speak with Marketplace for the story. In a statement, the association wrote that “The health, safety, and welfare of our guests has always been and continues to remain our top priority.”

None of the hotel chains agreed to be interviewed for the Marketplace investigation, although many committed to continuing to improve training and cleaning practices.