If you live in the US, it's a good time to get into the kohlzug.
A month ago, the US Center for Disease Control (CDC) reported that there were 17 cases of E. coli Food poisoning in seven states partially associated with romaine lettuce from a farm near Yuma, Arizona. Since then, there have been another 132 cases and one death reported in 22 other states, which makes this worst E. coli Outbreak since 2006, when 205 people fell ill and five died of contaminated baby spinach (Paywall).
Of the 29 states with confirmed Romain-related cases, California has the most, at 30, followed by Pennsylvania at 20. The outbreak has even reached an Alaska where, according to the Washington Post (Paywall), a prison inmate. At that point, the CDC recommends that consumers take steps to ensure that their romaine lettuce is not from Yuma, although the Watchdog group recommends that consumers avoid this particular green altogether.
E. coli is a type of bacteria commonly found in our intestines; Only certain strains are known to cause disease. In this case, the culprit is a strain of E. coli which is related to its number O1
As Quartz Chase Purdy has already noted, tracking outbreaks of food-borne illnesses is particularly difficult as there is a reporting problem. Even if a person gets sick enough to visit a hospital and receive the lab tests to confirm that the cause is a specific pathogen, it is difficult to pinpoint exactly what they ate, what made them sick. Even if a source is identified, it is not always clear where the food (paywall) originally absorbed the bacteria. It could be that the plants were irrigated by a contaminated source or that the farmers did not wash their hands after handling manure.
Officials from the CDC, the US Food and Drug Administration and various state health departments are still trying to pinpoint the source of contamination for the supply of lettuce outside the Yuma, Arizona region. Even if they find the cause of the problem, there will probably be more cases added to the E. Coli Outbreak due to a delay between a person visiting the hospital and her case being reported to health officials.