Three dozen more patients and two more states are officially part of an E. coli outbreak traced to romaine, according to a renewed public alert from the CDC.

As of this week 138 people across 25 states are on the books in the outbreak that was first announced Nov. 20, the Centers for Disease Control and Prevention reported. 

Since then the CDC has repeatedly stated that the outbreak strain of E. coli O157:H7 matches the strain responsible for outbreaks in 2017 and 2018. Those outbreaks were linked to leafy greens and romaine lettuce, respectively.

The Food and Drug Administration is also investigating the outbreak. An investigation team consisting of staff from FDA, CDC, the California Department of Public Health and the California Department of Food and Agriculture are attempting to identify any factors that could have led to contamination at a common farm identified by traceback, according to a statement posted today by the FDA.

“This investigation involves assessing and sampling soil, animal droppings, compost, water, and other potential environmental sources at the ranches of this grower. The samples and information collected during the farm investigations will be analyzed,” the FDA reported.

Of 136 ill people with information available in the outbreak, 72 hospitalizations have been reported, including 13 people who developed hemolytic uremic syndrome (HUS), a type of kidney failure. No deaths have been reported. 

Overall the patients range in age from less than 1 to 89 years old, with a median age of 26. Their symptoms began on dates ranging from Sept. 20 through Dec. 1. Additional victims are likely to be identified because partly because of the lag time between when a person becomes ill and when their diagnosis is reported. 

More victims are possible because of an ongoing threat from romaine, according to the CDC.

“CDC continues to advise that consumers not eat and retailers not sell any romaine lettuce grown in the Salinas, California, growing region. This includes all use-by dates and brands of romaine lettuce from this region,” according to the updated public alert.

“This advice includes all types of romaine lettuce grown in Salinas, California, such as whole heads of romaine, organic romaine, hearts of romaine, romaine in salad wraps, and packages of precut lettuce and salad mixes which contain romaine, including baby romaine, spring mix, and Caesar salad.”

Public health investigators have linked bagged salad products from Fresh Express and Ready Pac to the outbreak based on testing by the Wisconsin and Maryland state health departments. Specifically, an unopened package of Ready Pac Foods Bistro Chicken Caesar Salad collected from a sick person’s home and an unopened package of Fresh Express brand Leafy Green Romaine returned positive test results for E. coli.

The CDC reported additional products could be linked to the outbreak.

About E. coli infections
Anyone who has eaten any of the implicated products and developed symptoms of E. coli infection should seek medical attention and tell their doctor about their possible exposure to the bacteria. Specific tests are required to diagnose the infections, which can mimic other illnesses.

The symptoms of E. coli infections vary for each person but often include severe stomach cramps and diarrhea, which is often bloody. Some patients may also have a fever. Most patients recover within five to seven days. Others can develop severe or life-threatening symptoms and complications, according to the Centers for Disease Control and Prevention (CDC).

About 5 to 10 percent of those diagnosed with E. coli infections develop a potentially life-threatening kidney failure complication, known as a hemolytic uremic syndrome (HUS). Symptoms of HUS include fever, abdominal pain, feeling very tired, decreased frequency of urination, small unexplained bruises or bleeding, and pallor.

Many people with HUS recover within a few weeks, but some suffer permanent injuries or death. This condition can occur among people of any age but is most common in children younger than five years old because of their immature immune systems, older adults because of deteriorating immune systems, and people with compromised immune systems such as cancer patients.

People who experience HUS symptoms should immediately seek emergency medical care. People with HUS will likely be hospitalized because the condition can cause other serious and ongoing problems such as hypertension, chronic kidney disease, brain damage, and neurologic problems.