Investigators linked traces of salmonella typhi, the bacterium that causes typhoid fever, to a Goya brand frozen fruit product containing mamey fruit pulp. The fruit, also known as zapote and sapote is grown in Central and South America and often used in shakes and smoothies.

Typhoid fever has infected four southern Nevadans and five others in California. Typhoid fever is rare in the U.S., with an estimated 400 cases reported annually, health officials said.

Symptoms of typhoid fever include a sustained fever, stomach pains, headaches, anorexia, a slow heart rate, malaise, constipation or diarrhea or a nonproductive cough.

According to the CDC:

As of August 12, 2010, a total of 7 confirmed and 2 probable individuals infected with a matching strain of Salmonella serotype Typhi have been reported from 2 states since May 25, 2010. Confirmed cases are persons with illness on or after January 1, 2010 and a DNA fingerprint matching the outbreak strain. Probable cases are persons with a Salmonella Typhi infection and a strong epidemiologic link to the outbreak. The number of ill persons identified in each state with this strain is as follows: CA (3 confirmed and 2 probable) and NV (4 confirmed).

CDC and public health officials in two states conducted an epidemiologic study comparing foods eaten by ill and well persons. Among interviewed ill persons, 5 (71%) of 7 reported consuming frozen mamey fruit pulp in a milkshake or smoothie, also called a “batido” or “licuado.” Upon further investigation, it was found that 4 (80%) of 5 ill persons consumed Goya brand frozen mamey fruit pulp. Among well persons, 0 (0%) of 33 reported exposure to frozen mamey fruit pulp. No other food was found to be associated with illness. These results suggest that eating frozen mamey fruit pulp is a likely source of these illnesses. This investigation is ongoing. CDC and its public health partners will update the public on the progress of this investigation as information becomes available.

Mamey, also called “zapote” or “sapote,” is a tropical fruit grown primarily in Central and South America. It is prepared by removing the inner seed and consuming the flesh raw, or adding it to milkshakes, jellies, or other foods or beverages. When preparing frozen mamey fruit pulp, it is peeled and mashed, and then consumed as a shake or smoothie. Frozen mamey fruit pulp can be purchased in grocery stores throughout the U.S., and packages have a 2-3 year shelf life.