The Los Angeles County Department of Public Health (LAC DPH) is investigating a cluster of Brucella melitensis (brucellosis) infections among adults living in South Los Angeles County.
Each of the confirmed cases reported consumption of pasteurized cheese imported from Mexico, highlighting the serious health risks associated with raw or pasteurized dairy products.
Brucellosis is rare in Los Angeles County, with less than 15 cases reported each year. Most local cases are linked to unpasteurized imported cheese, occupational exposure to foreign animals, or accidental laboratory exposure. Although the current risk to the general public remains low, LAC DPH is issuing this advisory to inform health care providers and the public of the ongoing investigation.
“Consuming raw or unpasteurized dairy products poses a serious risk of infection,” said Dr. Sharon Balter, Los Angeles County Department of Public Health Acute Infectious Disease Control Program director. “We urge all residents to avoid products purchased locally or brought by family and friends from overseas.”
LAC DPH advises all residents to avoid consuming raw or unpasteurized dairy products, including cheese, brought into the country informally by family or friends or consumed while traveling to areas where brucellosis is prevalent. If you have recently consumed unpasteurized imported cheese and are experiencing symptoms such as fever, cold sweat, fatigue, or joint pain, please consult a medical professional immediately.
Brucellosis, also known as “Malta fever,” “tide fever,” or “Mediterranean fever,” is considered one of medicine’s “great imitators” due to its wide range of symptoms. Bacteria can enter the bloodstream through regional lymph nodes and spread throughout the body. The incubation period is about 1 to 4 weeks, but can take up to 6 months.
Symptoms include acute or insidious fever, night sweats, joint pain, headache, fatigue, loss of appetite, muscle pain, and weight loss. In severe cases, infection may cause arthritis, spondylitis, meningitis, endocarditis, orchitis/epididymitis, and organ involvement affecting the liver and spleen.
Brucella species have been designated as federal selection agents due to their low infective capacity and aerosolization potential. The laboratory must be notified before submitting specimens from suspected cases of brucellosis.
Health care providers should take the following steps:
- Suspect: Consider brucellosis in patients with fever, night sweats, fatigue, or arthralgia who have a history of consuming unpasteurized dairy products in the United States or while traveling to endemic countries.
- Testing: Order Brucella serology and blood cultures. Notify the laboratory before submitting the specimen so that appropriate biosafety precautions can be taken.
- Treatment: Consult an infectious disease doctor. Standard treatment is doxycycline plus streptomycin (14 to 21 days) or rifampin (6 weeks) for 6 weeks. For pediatric or pregnant patients, consider rifampin and TMP-SMX. If clinical suspicion is high, treatment is initiated without waiting for laboratory confirmation.
- Post-Exposure Prophylaxis (PEP): Consider PEP in conjunction with serologic and symptom monitoring for individuals exposed to common contaminated products or at high risk for confirmed cases.
- Reporting: Brucellosis must be reported to Public Health within one business day. If you suspect two or more related cases clustered together, notify Public Health immediately.
- Education: Advise patients to avoid all raw or unpasteurized dairy products, including those of unknown pasteurization status, whether purchased locally or while traveling.
