Consumers who have purchased raw milk from Our Lady of the Rock on Shaw Island, San Juan County, during the week of April 29 should discard it immediately due to the risk of Listeria contamination.
A routine sample of the unpasteurized milk from the dairy was taken April 30 and found to be contaminated with Listeria monocytogenes bacteria. The dairy operation was notified of the laboratory test results on Friday, May 11.
As of today, no illnesses have been reported as a result of the contamination. Individuals who have consumed the raw milk and become ill are advised to consult their physician or their local health department.
Five days to three weeks after ingestion, symptoms of Listeriosis will appear if a person becomes infected. A person with listeriosis usually has fever, muscle aches, and gastrointestinal symptoms such as nausea or diarrhea. If infection spreads to the nervous system, symptoms such as headache, stiff neck, loss of balance, confusion, obtundation or convulsions can occur. With brain involvement, listeriosis may mimic a stroke.
Human cases of Listeria are, for the most part, sporadic and treatable. Nonetheless, Listeria remains an important threat to public health, especially among those most susceptible to this disease. With the increase of the numbers of immunocompromised people, the risk multiplies. The fact that Listeria is a disease easily transmitted from mother to fetus through the placenta is worrisome to an expectant mother, especially since pregnant women themselves rarely show outward signs of such a devastating infection.