GENEVA, March 27 (Reuters) - Social unrest could erupt among the urban poor and marginalised in the West's biggest cities as they lack sources of income amid the COVID-19 crisis, the head of the International Federation of Red Cross and Red Crescent Societies (IFRC) said on Friday.

More than 80,000 people have tested positive for coronavirus in Italy since the outbreak emerged little more than a month ago and some 8,215 have died, far more than in any other country.

Francesco Rocca, an Italian who heads the world's largest disaster relief network, said that as well as social unrest the risk of suicide is increasing among vulnerable isolated people.

"We have a lot of people who are living very marginalised, in the so-called black hole of society... In the most difficult neighbourhoods of the biggest cities I am afraid that in a few weeks we will have social problems," Rocca told a U.N. news briefing.

"This is a social bomb that can explode at any moment, because they don't have any way to have an income," said Rocca, whose Geneva-based agency also deploys volunteers in hard-hit Spain and France.

He said the largest Western cities could see these problems emerge "in a few weeks".

Rocca, who is also president of the Italian Red Cross, spoke from Milan in the north, epicentre of the country's outbreak, after visiting Codogno, Bergamo, Brescia and Lodi.

Some people with a family who normally live on odd jobs that earn them 20-25 euros a time are often outside social assistance programmes, Rocca said, adding: "Think about the Roma camps."

In Italy, Rocca met mayors and some of the 180,000 Red Cross volunteers who visit elderly people confined to their homes, do their food shopping and get medicines from pharmacies. There is a shortage of ventilators in the north and the south, he said.

The IFRC, which has 14 million volunteers in 192 countries, and the International Committee of the Red Cross appealed on Thursday for 800 million Swiss francs ($830 million) to help vulnerable communities worldwide fight COVID-19. ($1 = 0.9639 Swiss francs) (Reporting by Stephanie Nebehay; Editing by Hugh Lawson)

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