BERLIN (REUTERS) - Four people who work at the same company in southern Germany have been infected with the coronavirus, and one of them contracted it from a colleague visiting their workplace in China, officials said on Tuesday (Jan 28).

The cases raise concerns about the spread of the flu-like virus that broke out in the central Chinese city of Wuhan at the end of last year and has killed 106 people and infected more than 2,800 people.

It spreads in droplets from coughs and sneezes and has an incubation period of up to 14 days.

In one of the first cases of person-to-person transmission outside China, a 33-year-old man apparently contracted the virus on Jan 21 during a training session with a Chinese colleague, the ministry said.

The three additional patients were being monitored in isolation at a clinic in Munich.

"A total of around 40 employees at the company have been identified as potential close contacts. As a precaution, the people concerned are to be tested on Wednesday," Bavaria's Health Minister Melanie Huml said in a statement.

German car parts supplier Webasto earlier on Tuesday said an employee at its headquarters in Stockdorf, Bavaria, had become infected following the visit of an employee from China.

A day earlier, it said an employee from Shanghai tested positive for the virus upon returning to China.

Confirmation of any sustained human-to-human spread of the virus outside of China, as well as any documented deaths, would bolster the case for reconvening the World Health Organisation's Emergency Committee to consider again whether to declare a public health emergency of international concern.

The independent panel last week twice declined to declare an international emergency.

Outside of China there have now been 45 confirmed cases in 13 countries, with no deaths so far, the WHO's spokesman Christian Lindmeier told a briefing in Geneva on Tuesday.

The WHO said a case in Vietnam involved human-to-human transmission outside China and a Japanese official has said there was a suspected case of human-to-human transmission there too.

WUHAN CONNECTION

Andreas Zapf, president of Bavaria's office for health and food safety, said on Tuesday the first person infected was 33 years old, lived in the district of Landsberg about 50km west of Munich and had come into contact with a Chinese lady on Jan 21.

Zapf said the Chinese woman was from Shanghai but her parents, who are from the Wuhan region, had visited her a few days earlier.

He added that she had arrived in Germany on Jan 19, appearing not to have any symptoms, but began to feel ill on her flight home on Jan 23.

She sought medical treatment after landing and tested positive for coronavirus.

When that information was relayed back to the German company, a male employee said he felt like he had flu over the weekend and was on Monday advised to get medical treatment.

The head doctor at the clinic where the man is being treated told a news conference the patient was awake and responsive and he did not think the man's life was at risk.

Health Minister Jens Spahn said the risk to people's health in Germany from the coronavirus remained low.