NEW YORK -- Bullish option traders are swarming to Europe as central bankers prepare to open the money spigots. 

OptionMonster's Heat Seeker tracking system detected aggressive call buying Wednesday in at least three funds that track equities across the Atlantic. The activity followed news reports that the European Central Bank will announce $58 billion in monthly asset purchases on Thursday. 

The iShares MSCI Italy (EWI - Get Report) fund appeared first, with more than 6,800 June 15s changing hands against open interest of just 156 contracts. Almost all of them priced for 35 cents.  

The iShares MSCI Germany  (EWG - Get Report) portfolio followed less than an hour later, with almost 70,000 April 30s purchased for 30 cents and 35 cents. Volume was more than 45 times open interest at the strike. 

Long calls lock in the price where investors can buy a stock, which lets them profit from a rally with limited risk. Their low cost can also result in significant leverage on a%age basis, but they can quickly lose value if shares fall. 

The EWI rose 1.77% to $13.81, and the EWG gained 0.65% to $27.85. Both have lagged the S&P 500 over the last six and 12 months but have started to catch up over shorter time frames. Economic data has also been firming recently, especially Germany's Zew sentiment index. 

A broader-based fund, the Vanguard FTSE Europe (VGK - Get Report) fund drew a bullish later in the session as well. Traders bought 21,000 February 54 calls for 60 cents against open interest of 393 contracts. The VGK rose 0.82% to $52.96.

Written by David Russell of  OptionMonster

Russell has no positions in any of the stocks mentioned in this article.

This commentary comes from an independent investor or market observer as part of TheStreet guest contributor program. The views expressed are those of the author and do not necessarily represent the views of TheStreet or its management.