The United States is currently experiencing a concerning rise in cases of cyclosporiasis, an intestinal infection caused by a tiny yet troublesome parasite.
According to recent figures released by the Centers for Disease Control and Prevention (CDC) on Wednesday, there are now over 11,500 reported cases scattered across 41 states. Of these, around 4,100 have been confirmed through laboratory testing, while approximately 7,400 cases remain to be officially verified.
In a parallel investigation, health authorities are delving into an outbreak that seems to be linked to the shredded iceberg lettuce used at Taco Bell outlets in five states: Indiana, Kentucky, Michigan, Ohio, and West Virginia.
This particular lettuce was supplied by Taylor Farms de Mexico, hailing from central Mexico. In response to these developments, the firm has proactively announced a voluntary recall of all its iceberg lettuce offerings.
While there’s been progress in identifying the affected regions and potential causes of the infection, several critical questions remain unanswered about the ongoing outbreak. Here’s what we’re still trying to uncover:
Scope of the outbreak
So far, the CDC has only confirmed 4,100 cases, but case counts reported by individual state health departments are higher.
The Michigan Department of Health and Human Services has confirmed at least 7,171 cases linked to an outbreak, according to
Dr. Zoe Weiss, director of clinical microbiology at Tufts Medical Center in Boston, told ABC News that it can be hard to determine the scope of the outbreak.
"I think in any outbreak situation, you're probably going to underestimate the actual number of cases," Weiss said. "There may be people who have very minor symptoms, and they never present to care, or people who just try to tough it out and eventually get better and again never present to care."
Although it usually takes about a week between when a person is infected with the parasite and when symptoms appear, it can range from two days to two weeks or longer, according to the
Wolfe noted that it does seem public health officials are getting a better understanding of how many cases there may be, likely due to better awareness and tracking of cases.
He said with more awareness, more patients with symptoms are likely coming forward seeking care and health care professionals also know to look for the illness.
"It's far from perfect because there's lots of people who will have symptoms that will self-resolve and they probably don't present, don't get tested and we never count their case, so we probably still grossly underestimate the number of cases that are out there, but we're getting a better handle on it," he said.
Source of the outbreak
The CDC and Food and Drug Administration have linked a multi-state outbreak to shredded iceberg lettuce from Taylor Farms.
Last week, Taylor Farms de Mexico issued a voluntary recall of all iceberg lettuce sourced from central Mexico, with the recall affecting 27 states. The recalled products were distributed from June 29 through July 16 and have best-if-used-by dates up to Aug. 3.
The recall includes Marketside-brand products available at Walmart, according to the FDA.
Weiss said it can take some time to determine that all the affected products are off the shelves.
"A lot of lettuce or produce in general can be sold under different names," she said. "It can be transported across state lines. There are opportunities for ambiguity about exactly where something was sourced from."
Despite the link between Taylor Farms iceberg lettuce and the multi-state outbreak, it is possible there are other potential sources, which officials are continuing to investigate.
Additionally, 29 other states are reporting dozens of cases. New York and Texas, which have not been linked to the outbreak, are each reporting between 161 and 300 cases, according to the