(Bloomberg) — Rising coronavirus cases in Thailand dimmed the outlook for a quick rebound in tourism, sending the nation’s equities benchmark to rank as the world’s worst performer.

Thailand’s SET Index’s 5.1% slump on Wednesday, most in six years, came after the government said confirmed cases of the virus rose by three to 40, fueling fears of a wider spread. The benchmark gauge’s 14% decline this year, the most among the world’s key equity indexes, has also plunged it into a bear market from a recent high.

The virus outbreak hit tourism-reliant Thailand particularly hard because Chinese tourists, its biggest source of foreign visitors, have all but vanished. Income from tourism, accounting for about fifth of the economy, tumbled last month. That’s exacerbated the effects of a severe drought, a delay in the government’s budget and an export slump in Southeast Asia’s second-biggest economy.

“Fundamentals and valuations are irrelevant now as the market is overwhelmed by fear,” said Namchai Techaratanawiroj, the head of research at LH Securities Co. in Bangkok. “Tourism is a key economic driver and Chinese tourists are the big spenders. There is still no end of this outbreak in sight.”

Other Southeast Asian markets have also been battered, with the Philippine Stock Exchange Index’s 11% slide year-to-date and the Jakarta Composite Index’s 10% putting them in the ranks of the world’s worst performing major equity markets in 2020, while Malaysia’s KLCI Index has tumbled out of a 12-year long bull run.

Overseas investors have pulled $1.18 billion from Thai equities this year, adding to an $11 billion withdrawal in the previous three years, according to data compiled by Bloomberg. Investors should hold onto their cash and be in “no rush” to buy equities during the ongoing coronavirus crisis, BBL Asset Management Co., which oversees about $29 billion of assets, said this week.