Japan's yen surged 2% on Monday with traders seeking cover in safe-haven currencies as fears about the coronavirus trumped central bank efforts to ease the pain, while the dollar stood tall despite the U.S. Federal Reserve slashing rates to zero.
The Fed cut U.S. interest rates on Sunday and said it would expand its balance sheet by at least $700 billion in the coming weeks.
The Bank of Japan said at an emergency meeting it would buy more corporate bonds, commercial debt and establish a new corporate lending scheme. New Zealand's central bank has also slashed rates in an emergency move.
But equity markets slumped again on Monday as traders fretted about the growing number of coronavirus cases worldwide.
In FX, investors dumped riskier currencies and bought into those they consider safer, although the size of the moves was not as large as last week.
MUFG analysts said policymakers could reduce volatility, but "the ultimate determinant will of course be evidence that COVID-19 is peaking".
The dollar dropped 2% to as low as 105.70 yen. That was still above last Monday's 101.18 yen.
The Swiss franc, another currency considered a safe haven, rose versus the dollar, with the dollar down 0.6% at 0.945 francs. The franc was unchanged versus the euro at 1.055 francs but near four-and-a-half-year highs.
The dollar, measured against a basket of currencies, was last up 0.1% at 97.95, off the day's highs. It had been falling as traders sold because of collapsing Treasury yields, but the U.S. currency has rebounded the past week as panicked investors stocked up on the world's most liquid currency.
The euro jumped 0.5% to $1.1168 after earlier reaching $1.124. Sterling sank as low as $1.2250, its weakest since October.
Volatility, which had doubled in a few weeks, has subsided in both euro/dollar and across currencies, though it remained elevated.
The People's Bank of China injected 100 billion yuan ($14.28 billion) into financial institutions on Monday.
The move came minutes before data showed China's retail sales, industrial output, and fixed-asset investment all tumbled in January and February.
"The measures introduced to stop the spread of the virus in China may have led to a sharper slowdown in activity than will be the case elsewhere, but it's clear that the measures central banks have taken, and whatever they do next, cannot prevent a major economic hit being felt globally," Societe Generale strategist Kit Juckes said.
The offshore yuan rose 0.1% at 7.0206 yuan per dollar.
The Reserve Bank of New Zealand cut rates by 75 basis points to a record 0.25%. The Reserve Bank of Australia added A$5.9 billion ($3.63 billion) to the banking system.
The New Zealand and Australian dollars fell 0.3% but were off the day's lows.
Currencies hit hard by risk aversion, such as the Russian rouble, Mexican peso and Norwegian crown, fell in many cases towards record lows.