As a deadly E. coli outbreak in Germany worsens, U.S. regulators say the American food supply remains safe, while meat processors say stepped-up safety practices in recent years have reduced the chances of a similar outbreak here.

More than 1,800 have been sickened and 18 have died in the outbreak, which is believed to be linked to tainted vegetables carrying a rare but dangerous E. coli strain that’s never been reported in the U.S. food system.

E. coli has been a concern for the U.S. beef industry for years, though illnesses typically resulted from a different strain, known as O157:H7, which contaminated ground beef. But meat does not appear to be connected to the Europe outbreak at all, U.S. industry officials said.

Moreover, sanitation improvements at slaughter plants have sharply reduced the prevalence of E. coli over recent years, according to the American Meat Institute. Stricter food safety practices “have served us well,” said Janet Riley, a spokeswoman for the Washington, D.C., institute, which represents most U.S. processors.

The U.S. beef industry “has been held up as a model for others in how to prevent and control pathogenic bacteria like E. coli O157:H7,” Riley said in a June 2 e-mail. “The good news is that the strategies that have helped reduce E. coli O157:H7 appear to work equally well on other strains.”

Citing government studies, the American Meat Institute last year said the prevalence of E. coli O157 was as low as it’s ever been, with beef samples testing positive for the bacteria dropping 70 percent over from a decade ago. E. coli can be found in the intestines of cattle.

In the Germany outbreak, the E. coli strain was identified as O104:H4, one of about eight “Shiga toxin” producing strains – or “STECs” – that are believed to be the most dangerous for humans. Most reported U.S. infections involve O157, which can cause bloody diarrhea, severe stomach cramps and vomiting and is responsible for an estimated 70,000 illnesses and 80 deaths every year, according to the Centers for Disease Control and Prevention.

Germany’s outbreak is unusually severe compared with outbreaks in the U.S. over the past two decades, food safety experts said. “This one’s off the charts,” said Scott Hurd, an Iowa State University professor who specializes in foodborne pathogens. Still, U.S. consumers shouldn’t be concerned, he said.

In a June 3 conference call with reporters, U.S. food regulators downplayed the prospect that O104 may contaminate the domestic food supply, noting that tainted cucumbers, lettuce or tomatoes from Europe are suspected as the cause of the outbreak in Germany. Regulators have increased surveillance of vegetables from the European Union, but noted that relatively little of U.S. fresh produce imports come from the region.

U.S. consumers “should feel safe,” David Elder, director of regional operations for the U.S. Food and Drug Administration, said during the call.

JBS USA, the country’s third-largest beef processor, says sanitation methods such as acid rinses applied to cattle carcasses are effective at killing E. coli and other bacteria.

“When we knock down O157, we’re knocking down all pathogens,” JBS spokesman Chandler Keys said in a June 3 phone interview. “Our whole process is to try to get that carcass into the cooler with zero pathogens.”

Earlier this year, JBS installed video cameras in its eight U.S. beef plants, Keys said. The video is remotely monitored by an outside firm, helping JBS identify areas on its processing lines where contamination may occur.

The cameras “are helping us get to astronomical levels of compliance” with food safety regulations, he said. JBS, owned by Brazil-based meat processor JBS SA, has capacity to slaughter about 28,600 head of cattle a day, according to Cattle Buyers Weekly.

Cargill Meat Solutions, the second-largest U.S. beef processor behind Tyson Foods, Inc., is monitoring the situation in Europe, company spokesman Mike Martin said.

“As this appears to be a new strain that has been linked to vegetables and has not been found in meat, there is nothing more we can add to the discussion at this time,” Martin said in a June 3 e-mail.

While reported E. coli illnesses from tainted beef have declined in recent years, the U.S. food industry still must remain vigilant for lesser-known, non-O157 strains, food safety experts said. More research is needed to better understand where the rare O104 strain originates and how it can contaminate food, said Michael Doyle, director of the University of Georgia’s Center for Food Safety.

“We don’t have it here yet that we know of,” Doyle said. “But that’s not to say it won’t get here.”