Four years after a salmonella outbreak tied to peanut butter, it's happened again -- despite stricter industry standards.

Arecall of Trader Joe's peanut butter a week ago has been expanded tomore than 100 products sold nationally in many other supermarkets.

Atleast 30 people have been infected with salmonella Bredeney in 19states, according to the Centers for Disease Control and Prevention.Four were hospitalized. No deaths have been reported.

No salmonella has been found in the peanut butter, but 12 of the people who got sick reported eating it.

Theillnesses were traced to Valencia Creamy Salted Peanut Butter producedby Sunland Inc. of Portales, N.M. Trader Joe's also recalled Valenciapeanut butter made with roasted flaxseeds and almond butter with roastedflaxseeds.

So far, the only product directlylinked to the outbreak is Trader Joe's peanut butter, said Sunland vicepresident Katalin Coburn.

Still, Sunlandexpanded the recall to include almond butter, peanut butter, cashewbutter, tahini (sesame seed butter) and roasted blanched peanut productsunder various names manufactured between May 1 and Sept. 24. Theproducts were distributed nationally to large supermarket chains underthe Sunland and store brand labels and were sold online.

Allthe products were made on the same production line. Because the sourceof the contamination isn't known, "we could not take the risk ofjeopardizing anyone," Coburn said.

Infectionwith the salmonella bacteria can cause salmonellosis, an illness thatcan mean serious and sometimes fatal infections in young children, frailor elderly people, and those with weakened immune systems.

Inhealthy people it can cause fever, diarrhea, nausea, vomiting andabdominal pain.It's unknown how or whether the peanuts werecontaminated. If they were, poor manufacturing processes or insufficientroasting could have been the cause, said Michael Doyle, director of theCenter for Food Safety at the University of Georgia in Griffin.

In2008, as many as nine people died and more than 700 people in 46 stateswere sickened by peanut butter and other products made by PeanutCorporation of America. No national brand was involved, but more than125 products were recalled.

An FDA inspectionof the plants that produced the company's products found them to befilthy and infested with birds and rodents.Until then, U.S. food safetyexperts had not considered peanut butter a high-risk food. They reactedby establishing a standard for roasting nuts hot enough to killdangerous pathogens. An American Peanut Council study suggested that arange between 264 degrees at 47 minutes to 295 degrees at 14 minuteswould reduce salmonella levels 100,000 times.

Sunland's peanuts are roasted at 330 to 345 degrees for 30 to 33 minutes, Coburn said.