A total of 23 Costa Coffee stores received two or less stars in their most recent hygiene inspections, according to the http://www.dailymail.co.uk/news/article-3267212/Dead-mouse-risk-killer-bacteria-Squalor-inside-Costa-coffee-shops-revealed-chain-ordered-clean-act.html" target="_blank" rel="noreferrer">Daily Mail.
The newspaper revealed the findings of the Scores on the Doors initiative following a Freedom of Information request.
One incident included a dead mouse being found in a back room of the Costa next to St Paul's Cathedral - it was reported to have been there 'for some time'. Mice droppings were also found on shelves, surfaces and floors of the store.
An inspection of the Costa at the Royal Hampshire County Hospital carried out in June, found paninis at risk of contamination with clostridium botulinum - a form of bacteria that can cause paralysis and death.
Cockroach and rat infestations were also discovered at an outlet in Broadstairs, Kent, with inspectors likening the store to a 'building site'.
Other branches were found to have no hot water for staff to wash their hands after using the toilet, while the Costa store in Liverpool shopping centre was closed for a week in February after inspectors returned a zero-star rating.
However, the findings are not representative of the entire Whitbread-owned chain, as most of Costa Coffee's shops scored five stars, or received 'good' or 'satisfactory' ratings.
Responding to the investigations Costa said the hygiene failings were acted on immediately.
Jim Slater, managing director, Costa UK and Ireland, said: "At Costa the health and wellbeing of our customers is our number one priority which is why we personally check every single one of our 2,000 stores regularly. According to EHO figures 98% of Costa stores score good to very good in inspections, but in our opinion anything less than a three star satisfactory rating is unacceptable and requires immediate attention.
"We would like to reassure all customers that these are isolated incidents and we have a robust system, supported by external auditors to immediately address concerns raised either by the EHO or our own checks."
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