US chip giant Intel, Facebook, Chinese phonemaker Vivo and Cisco all withdrew from the Mobile World Congress over coronavirus fears Tuesday, joining other industry heavyweights pulling out of the world's top mobile fair.

The annual Barcelona-based congress normally draws more than 100,000 people, but this year, participation has been hit by the outbreak of the COVID-19 virus, which has claimed more than 1,000 lives since first emerging in China.

Over the past week, a string of major tech names have dropped out, among them Sony, Sweden's Ericsson, South Korean giant LG and Japan's NTT DoCoMo, raising questions about whether the event would be cancelled.

"The safety and wellbeing of all our employees and partners is our top priority, and we have withdrawn from this year's Mobile World Congress," said an Intel statement sent to AFP.

Facebook, which operates Instagram and WhatsApp, said in a statement that it was pulling out of the Barcelona event because of public health risks related to the virus.

Vivo, which is one of the world's top five smartphone manufacturers, also confirmed it would not participate in the show, a key date in the tech calendar where firms unveil their latest gadgets and innovations.

"In light of the current situation, we have taken the decision not to attend MWC 2020 or any other associated event in Barcelona at the same time" it said, pledging to postpone the presentation of its latest mobile offering.

"The health and security of our employees and the wider public are a priority for us," it said.

Big tech names have pulled out of the Barcelona conference over COVID-19 virus fears
Big tech names have pulled out of the Barcelona conference over COVID-19 virus fears AFP / Anthony WALLACE

Vivo is the second Chinese firm to withdraw from the show after Umidigi, a smaller handset maker, pulled out on Monday.

US tech company CISCO had taken the "difficult decision to withdraw" from the event due to concerns over the virus, the company said in a statement on Twitter.

For now, China's top smartphone manufacture Huawei as well as its smaller rival ZTE are still set to attend and have said their executives and staff would undergo a self-imposed two-week quarantine period before appearing at the show.

ZTE has also said its stand and equipment would be disinfected daily, with all of its booth exhibition staff brought in from countries outside of China, mainly Europe.

US chipmaker Nvidia has also cancelled its appearance at the show, which is due to run from February 24-27 and normally includes between 5,000 to 6,000 participants from China, according to GSMA, the mobile trade association which organises the show.

On Sunday, the association said it would step up security measures to try and reassure exhibitors, saying it would have staff on hand to take visitors' temperatures and would impose restrictions on visitors coming from China.

By Tuesday, the death toll from the virus had risen to 1,016, with more than 42,000 people infected.

Almost all of the deaths and infections have been in mainland China, although the virus has since been detected in 25 countries, in what the World Health Organization on Tuesday said posed a "very grave threat" for the world.