U.S. officials have linked recalled black fungus to a Salmonella outbreak that has sickened dozens of people in 10 states. The edible fungus is also known as wood ear mushrooms.

At least 41 patients are reported in the outbreak according to the Centers for Disease Control and Prevention outbreak announcement today. Many of them reported eating wood ear mushrooms in restaurants before becoming ill, according to the Food and Drug Administration. At least four people have required hospitalization.

Wismettac Asian Foods Inc. has recalled the mushrooms. The California company reports distributing the implicated fungus to restaurants in 32 states and Canada. Federal officials in the United States and Canada, as well as state officials, are investigating to discover the source of the contamination of the Chinese mushrooms.

Mushroom Council Senior Vice President Eric Davis says this recall is in no way related to fresh, cultivated mushrooms produced in the United States. He also stressed that fresh mushrooms are not implicated.

California health officials found the Salmonella in samples of the edible fungus, spurring the company to initiate the recall.

“Wood ear mushrooms imported by Wismettac Asian Foods Inc. were only sold to restaurants and were not available directly to consumers. Although these items have been recalled, concerned or high-risk individuals should check with their restaurant to confirm that any wood ear mushrooms that have been used or are being used are not part of this recall,” the FDA advised in an update today.

Wood ear mushrooms are also commonly referred to as Kikurage, Dried Black Fungus, Dried Fungus, or Mu’er/Mu Er/Mu-Err, according to the CDC. The public health agency is advising anyone who has such food on hand to throw it away unless they know for sure it is not subject to the recall.

The company reports that the mushrooms were distributed to restaurants in six-packs of 5-pound bags labeled as Shirakiku brand Black Fungus (Kikurage) with Universal Product Code (UPC) bar code 00074410604305, item #60403, and imported from China.

Clusters of ill people have been identified in relation to several restaurants. Many of them reported eating wood ear mushrooms or ramen containing wood ear mushrooms in the week before their illnesses started. 

“FDA and states are conducting a traceback investigation to identify the source of the wood ear mushrooms eaten by ill people. A review of records collected to date identified that Wismettac Asian Foods Inc., supplied wood ear mushrooms (dried fungus) to the illness cluster restaurants,” according to the CDC’s outbreak announcement posted today.

“The California Department of Public Health collected dried fungus at one of the restaurants linked to an illness cluster for testing. Testing identified Salmonella in a sample of dried fungus distributed by Wismettac Asian Foods Inc. (Whole genome sequencing) analysis is being done to determine if the Salmonella identified in the dried fungus is the same as the Salmonella from ill people.

A wide range of people is listed as outbreak patients, with their illnesses having begun between Jan. 21 through Aug. 26, according to the CDC. 

Ill people range in age from 2 to 74 years old. Of 32 ill people with information available, four hospitalizations have been reported. No deaths have been reported.

Illnesses might not yet be reported due to the time it takes between when a person becomes ill and when the illness is reported. This takes an average of two to four weeks.

About Salmonella infections
Food contaminated with Salmonella bacteria does not usually look, smell, or taste spoiled. Anyone can become sick with a Salmonella infection. Infants, children, seniors, and people with weakened immune systems are at higher risk of serious illness because their immune systems are fragile, according to the CDC.

Anyone who has eaten any of the recalled mushrooms and developed symptoms of Salmonella infection should seek medical attention. Sick people should tell their doctors about the possible exposure to Salmonella bacteria because special tests are necessary to diagnose salmonellosis. Salmonella infection symptoms can mimic other illnesses, frequently leading to misdiagnosis.

Symptoms of Salmonella infection can include diarrhea, abdominal cramps, and fever within 12 to 72 hours after eating contaminated food. Otherwise, healthy adults are usually sick for four to seven days. In some cases, however, diarrhea may be so severe that patients require hospitalization.

Older adults, children, pregnant women, and people with weakened immune systems, such as cancer patients, are more likely to develop a severe illness and serious, sometimes life-threatening conditions.

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