New York (AFP)

Wall Street, on a roller coaster since the beginning of the week, was again under heavy pressure Thursday as investors struggle to assess the consequences of the spread of the new coronavirus.

Its flagship index, the Dow Jones Industrial Average, fell 3.58% to finish at 26,121.28 points.

The highly technological Nasdaq plunged 3.10% to 8,738.59 points, when the S&P 500, which represents the 500 largest companies listed on the New York Stock Exchange, fell 3.39%. at 3,023.94 points.

After having cashed in their worst week since 2008, the indices are still fluctuating according to the headlines about the epidemic and have alternated falls and rebounds since the start of the week.

Hit hard by the spread of the virus around the world, airlines were particularly affected Thursday. United Airlines collapsed by 13.25%, American Airlines by 13.24%, JetBlue by 10.81% and Delta by 7.20%.

The International Air Transport Association (Iata) has estimated that the spread of the Covid-19 epidemic could cost the sector up to $ 113 billion this year.

But all companies are potentially affected by the epidemic.

"Markets can handle bad news because they can quantify it," says Quincy Krosby of Prudential. "Managing uncertainty is much more complicated," she adds.

However, with the epidemic of the new coronavirus, uncertainty concerns both the extent of its spread in the world and its consequences on the economy.

"Companies have not yet gone into too much detail, except to say that the epidemic had disrupted their supply chains and was going to affect their business," she said.

If the epidemic is still spreading a lot, "the question will be whether they start to lay off staff", and then "what will be the impact on consumer spending, knowing that the latter represent 68% of gross domestic product, "adds Krosby.

If Americans stop consuming, going out, going to restaurants, "it could badly affect small and medium-sized businesses", fears the specialist.

As a sign of the rush of investors towards assets deemed less risky, the 10-year rate on US Treasury bonds fell again on Thursday, falling for the first time below the 0.9% threshold. Around 9:00 p.m. GMT, it was evolving at 0.922% against 1.052% the day before at the close.

Wall Street had however welcomed Wednesday with enthusiasm the return of Joe Biden to the rank of favorite of the Democratic primaries against Bernie Sanders, supporter of a major overhaul of the health insurance system.

The impression that authorities around the world seemed to be stepping up to fight the spread of the epidemic and support the economy had also contributed to the renewed confidence of investors.

But Thursday, anxiety took over among Wall Street brokers from the start of the session, and even more after the state of emergency declared by the State of California.

© 2020 AFP