Vienna’s public lavatories were the focus of the work by the Global Food Safety research group at the Vetmeduni Vienna.
Dagmar Schoder, head of the global food safety research group at the university, said it is now standard for businesses to ensure the highest level of hygiene.
“But more attention should be paid to the hygiene of persons making deliveries. Delivery persons and workmen often wear safety shoes with a deep tread.
“It is especially important that these persons regularly clean and disinfect their shoes.”
Transmission by shoes
Transmission of Listeria via fomites, such as shoes, has been suspected at food processing facilities prior to outbreaks due to food contamination, found previous research.
The study looked at 224 public restrooms in Vienna for the presence of Listeria monocytogenes.
L. monocytogenes is a so-called environmental bacterium which is highly adaptable and resistant.
Results suggested that shoes, particularly those with deep type treads, are important for the distribution of Listeria spp.
This may reflect a greater opportunity for dirt to adhere to soles. However, it cannot be excluded that people who wear deep tread shoes frequent particular environments where Listeria spp. are more common than elsewhere, such as visitors from the countryside, said the study.
Previous studies at the University of Veterinary Medicine Vienna have shown that L. monocytogenes is more prevalent in rural areas than in cities.
It also found soil environments are one of the most important reservoirs for L. monocytogenes.
No Listeria spp. were found on shoe soles that had smooth treads, while it was detected on eight of 41 samples from medium depth tread types and three from 32 examples of deep tread.
Detectamet: shoe covers growth
In a separate development, Detectamet has said interest in its fully detectable shoe covers has increased tenfold since they were launched at the end of 2014.
The plastic cover is made using Detectamet’s metal and X-ray visible polymer. The shoe covers can be identified by standard detection/inspection systems.
They are used for visitors to cover their outdoor shoes and interdepartmental staff can use them to re-cover footwear as they move to and from restricted areas.
Sean Smith, Detectamet’s CEO, said customers have learned the material is more durable and samples have been requested to be trialled across the UK.
“We carried tests on the pre-production samples and we were very impressed with both the detectability and the durability of the new covers,” he said.
“Some of our factory staff wore them for a day and compared them with the old specification worn for a similar period of time.
“I’ve experienced the use of similar non-detectable over shoes and they can wear out before lunchtime.”