The dollar advanced on Thursday as a sell-off in global equities weighed on risk appetite and drove haven demand for the US currency.
Fears over global growth hit commodity-linked currencies the hardest.
By midday in New York, the Australian dollar fell 1.6% to USD 1.0362 against the US dollar, while the Canadian dollar fell 1.2% to CAD 0.9925 and the New Zealand dollar dropped 1.5% to NZD 0.8248.
The dollar also rose 1% to USD 1.4292 against the euro and was up 0.6% at USD 1.6430 against the pound.
The dollar eased 0.1% to Y76.50 against the yen, however, as haven demand also boosted the Japanese currency.
The drop in global stocks also boosted haven demand for the Swiss franc, thwarting the Swiss National Bank's latest efforts to weaken its currency.
Earlier in the session the franc weakened on speculation that the SNB used the foreign exchange swaps market to stem its strength.
Traders said that the central bank had been active in the swaps, or forwards market, to sell the franc in short-dated maturities in a bid to saturate it with cash and drive down interest rates while promising to buy the currency back at a later date.
The move pushed Swiss interest rates implied by the futures market deeper into negative territory.
Analysts questioned whether such action, essentially an interest rate operation, could help to stabilise the euro against the Swiss franc over the longer term, however.
Ulrich Leuchtmann at Commerzbank said if the SNB wanted to fight Swiss franc strength, it would have to take more decisive action.
"If they do not decide to do so, the euro will most likely come under massive pressure against the Swiss franc. Parity would be likely," he said.
"We can hardly believe that such a massive policy error is likely. Accordingly, we expect the SNB to take more decisive action soon, especially FX market intervention."
The Swiss franc climbed 1.3% to SFr1.1252 against the euro and rose 0.3% to SFr0.7869 against the dollar.
