The value of the net long dollar position was $21.21 billion in the week ended Feb. 25, compared with $14.78 billion the previous week. The Dec. 3 level for net long US dollars was the highest since late June.
US dollar positioning was derived from net contracts of International Monetary Market speculators in the Japanese yen, euro, British pound, Swiss franc and Canadian and Australian dollars.
In a wider measure of dollar positioning that includes net contracts on the New Zealand dollar, Mexican peso, Brazilian real and Russian ruble, the US dollar posted a net long position of $18.082 billion, up from $11.183 billion a week earlier.
The dollar benefited last week as a safe haven amid fears about the outbreak of a coronavirus that originated in China and has spread around the world. So far this year, the dollar index has risen 1.7%.
The latest figures from the World Health Organization showed that more than 82,000 people have been infected, with over 2,700 deaths in China and 57 deaths in 46 other countries. Mexico, Nigeria, Estonia, Denmark, the Netherlands and Lithuania reported their first cases, all with travel histories connected to Italy, the worst affected European country.
Some analysts said the dollar's rally could pause as investors priced in more aggressive interest rate cuts by the US Federal Reserve as the coronavirus spreads.
Investors are expecting the Fed to cut rates at its policy meeting next month.