ZURICH, Oct. 7 (AFP) - The wealth of the world's dollar billionaires reached record heights despite the global COVID-19 crisis, notably thanks to a strong comeback by tech and health giants, said a report published Wednesday (Oct 7).

By the end of July, the cumulative wealth of billionaires stood at around US$10.2 trillion, according to a study conducted by Switzerland's biggest bank UBS and accounting giant PricewaterhouseCoopers.

That exceeded the previous peak of US$8.9 trillion recorded in 2017.

The annual inventory of the super-rich's fortunes identified 2,189 billionaires at the end of July - 31 more than in 2017.

However, the figures mask significant changes during the stock market crash in March, which saw some tumble out of the billionaires' club, before a sharp rebound in technology and health stocks began.

"Fortunes are polarising as business innovators and disruptors deploy technology to be among the leaders of today's economic revolution," the report said.

"The COVID-19 crisis just accentuated this divergence" between tech, health and industry innovators who were already on the rise, and other billionaires who are "on the wrong side of economic, technological, societal and environmental trends" and are becoming less wealthy.

The coronavirus pandemic had a dramatic impact on the world's billionaires.

The wealth of billionaires fell 6.6 per cent in February and March, before bouncing back by 27.5 per cent between April and the end of July, notably to the benefit of technology giants.

Across 2018, 2019 and the first seven months of 2020, the fortunes of four billionaires in the tech sector increased by 42.5 per cent, putting their cumulative fortune at an estimated US$1.8 trillion.

Health sector billionaires recorded an increase of 50.3 per cent, with a cumulative fortune estimated at US$658.6 billion.

By comparison, the net worth of billionaires in industries such as entertainment, real estate and financial services only increased by no more than 10 per cent.