July 21, 2008 -- A fresh jalapeño pepper grown in Mexico and processed in Texas has tested positive for the strain of salmonella that has sickened more than 1,200 people in recent months, food safety and health officials said today.

The U.S. Food and Drug Administration's associate commissioner for foods, David Acheson, said there has been a "significant break in the salmonella investigation," stressing, however, that the probe is ongoing.

As a result of the finding, the FDA is asking people nationwide to avoid eating fresh jalapeño peppers, serrano peppers and foods made with fresh jalapeño peppers. Pickled and preserved jalapeños are still safe to eat.

The pepper that tested positive was obtained at a produce distribution center called Agricola Zaragosa, in McAllen,Texas, officials said. That distribution center has since recalled all peppers that passed through its plant. All the other samples that have since been taken at that facility have tested negative for the outbreak, the FDA said.

And although the pepper in question was grown on a farm in Mexico, the FDA has yet to determine whether it was contaminated there or later along the supply chain.

"Contamination could have occurred anywhere from the farm all the way to the facility," Acheson said.

Dr. Robert Tauxe, deputy director of the Centers for Disease Control's division of foodborne, bacterial and mycotic diseases, said 1,251 people in 43 states and the District of Columbia have become sick from salmonella since April. There have been 229 hospitalizations and two deaths as a result.

"This outbreak continues," Tauxe said today. "This is 14 more cases than had been reported as of last Friday."

Indeed, the source of the salmonella outbreak has been a complex mystery in recent months, as officials first focused on tomatoes as the likely culprit. But the FDA last week gave consumers the go-ahead to eat tomatoes again.

Officials cleared tomatoes because the farms that may have shipped them at the beginning of the outbreak in May are no longer harvesting them, and food safety officials also said they've found no contamination along the tomato-distribution chain.

Food safety officials last week said there could have been cross-contamination between tomatoes and peppers at packing or washing stations before the foods made their way to restaurants and grocery stores.

"This has been one of the most complex outbreaks that I personally have ever been involved with," Acheson said today.

Now that a pepper has tested positive for salmonella, the FDA said it is looking up and down the entire production chain that pepper would have passed through for more clues. Acheson said that includes looking at records to find where peppers from that distribution center were sent.

"We are very actively pursuing and investigating several clusters of cases who all ate at the same restaurant or group of restaurants," Tauxe said. "We are also conducting extremely detailed interviews in the heartland of the outbreak, if you will, down in the Southwest."