HSBC has evacuated a floor of its Canary Wharf office tower after an employee was confirmed to have caught coronavirus.

The bank has sent 100 people home and ordered a deep clean of the 10th floor, which houses its research department. This has so far not affected HSBC’s trading floor, which carries out large transactions on financial markets for big institutions.

HSBC said: “We have been informed that one of our employees at 8 Canada Square has been diagnosed with Covid-19. This colleague is under medical supervision and has self-isolated. We are working closely with the health authorities.

“We are deep-cleaning the floor where our colleague worked and shared areas of the building. Colleagues on that floor, and others who came into contact with him, have been advised to work at home. Based on medical and official advice the building remains open and operates as normal. Our first priority and concern is the health of our employees and customers – and we are encouraging our colleagues to monitor their health carefully and stay at home or call a doctor if they feel unwell.”

About 20 people were sent home from the global banking division on the second floor of the HSBC tower on Wednesday, after an employee had contact with someone who subsequently developed coronavirus symptoms, according to a person familiar with the matter.

HSBC has also banned all non-essential travel. The floor evacuation was first reported by Financial News.

Q&A How can I protect myself and others from the coronavirus outbreak? Show Hide The World Health Organization is recommending that people take simple precautions to reduce exposure to and transmission of the coronavirus, for which there is no specific cure or vaccine. The UN agency advises people to: Frequently wash their hands with an alcohol-based hand rub or warm water and soap

Cover their mouth and nose with a flexed elbow or tissue when sneezing or coughing

Avoid close contact with anyone who has a fever or cough

Seek early medical help if they have a fever, cough and difficulty breathing, and share their travel history with healthcare providers

Advice about face masks varies. Wearing them while out and about may offer some protection against both spreading and catching the virus via coughs and sneezes, but it is not a cast-iron guarantee of protection Many countries are now enforcing or recommending curfews or lockdowns. Check with your local authorities for up-to-date information about the situation in your area. In the UK, NHS advice is that anyone with symptoms should stay at home for at least 7 days. If you live with other people, they should stay at home for at least 14 days, to avoid spreading the infection outside the home.

Other companies are also making plans to send staff home, if the epidemic escalates. Tesco on Wednesday told more than 5,000 staff at its Welwyn Garden City headquarters in Hertfordshire and other offices to prepare to work from home.

Lloyd’s of London, the world’s biggest insurance market, this week announced “emergency trading protocols” to allow the market to remain open if the situation escalates. Lloyd’s 1,000 staff, along with thousands of brokers and underwriters who work for other firms, would be asked to work from home and to resort to electronic trading.

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Britain’s financial services regulator said on Wednesday it has “no objection” in principle to City staff working remotely due to coronavirus quarantine measures.

However, the Financial Conduct Authority said firms must take all reasonable steps to keep operating effectively and support their customers.

The FCA said: “For example, we would expect firms to be able to enter orders and transactions promptly into the relevant systems, use recorded lines when trading and give staff access to the compliance support they need. If firms are able to meet these standards and undertake these activities from backup sites or with staff working from home, we have no objection to this.”