One person in California has died over an E.coli outbreak speculated to have been caused by romaine lettuce, food officials confirmed May 2.

According to the Centers for Disease Control and Prevention, three more states have been ravaged by this outbreak, bringing the total number to 25, with 121 people reported sick.

The current romaine lettuce situation is being hailed as the worst E.coli outbreak since 2006 when illnesses linked to spinach took three lives and made over 270 people sick.

With the numbers increasing every week, this outbreak is fast approaching the aforementioned 2006 fiasco. The CDC says more than half of those who have become ill have been hospitalized.

The strain of E.coli linked to romaine lettuce produces a toxin called Shiga that induces diarrhea and other potentially severe symptoms, including kidney failure in some cases. The CDC confirms that so far, 14 people have this kidney damage called hemolytic uremic syndrome, which puts them at risk of death.

Don't Eat Lettuce

All the contaminated romaine lettuce has been traced to farms in Arizona.

"Do not eat or buy romaine lettuce unless you can confirm it is not from the Yuma, Arizona growing region," the CDC cautions. "Restaurants and retailers should ask their suppliers about the source of their romaine lettuce."

Health officials warn that washing lettuce doesn't cut it.

This bacteria can actually get inside the lettuce leaf," says Ian Williams, the chief of CDC's Outbreak Response and Prevention Branch. "Washing it doesn't make it safe."

E.Coli Romaine Lettuce Outbreak

E.coli typically lives in animal intestines such as cows and pigs. In fact, in the 1990s, most E.coli illnesses were linked to contaminated hamburger products. Improvements in the livestock industry have lowered the number of meat-related E.coli outbreaks but conversely, E.coli contamination of leafy vegetables have been rising.

On average, people get sick three to four days after first ingesting the bacteria, according to the CDC. Most people experience diarrhea — often bloody ones, including vomiting, and severe stomach cramps. Most people recover within a week, while some cases last longer and can be more severe, requiring hospitalization.

California is the state with the most hospitalizations at 24, followed by Pennsylvania with 20, then Idaho with 11. The most recent case was reported April 21. The person in California who died over the outbreak has not been identified.

The California Department of Public Health has confirmed the death to CBS News but did not provide any more details, citing patient privacy laws.