Brucellosis and unpasteurised dairy

For many people, fresh milk and homemade cheese are the familiar taste of home. But if the milk or cheese comes from an infected animal and has not been pasteurised, it can pass the Brucella bacterium to people. The illness it causes is called brucellosis, or Malta fever. This article is for people who have a fever and joint pain and remember eating such dairy, or who want to protect their family.

How does brucellosis reach people?

The CDC names several routes:

• drinking raw milk, or eating dairy (milk, cheese, ice cream) made from infected milk
• eating undercooked meat from an infected animal
• direct contact with an infected animal or its fluids
• breathing in a contaminated environment
• working in a laboratory

WHO says most cases come from unpasteurised goat or sheep milk or cheese. Farmers, butchers, hunters, vets and laboratory workers are more exposed. The reassuring point is that spread from person to person is very rare.

What are the symptoms?

The illness usually starts like a bad flu: fever, weakness, sweating, headache, muscle, joint and back pain, and loss of appetite. WHO says symptoms usually begin two to four weeks after exposure, and can take anywhere from one week to two months. Sometimes the symptoms are mild and the illness is missed.

If it is not treated, or treatment is incomplete, the infection can become chronic. The CDC names arthritis, swelling of the testicles, heart infection, memory problems or confusion, depression, and an enlarged liver and spleen.

Why can it be diagnosed late?

Because the symptoms look like those of many other illnesses. The CDC says early symptoms are not specific and diagnosis is made with tests. That is why the doctor asks you about animals, raw milk, local cheese and travel. If you remember any of these, be sure to say so. This history helps choose the right test. The tests include an antibody test on the blood and sometimes a culture, and sometimes a second sample is needed a few weeks later.

How can we lower the risk?

The CDC says:

• Do not eat undercooked meat.
• Do not eat or drink unpasteurised dairy (milk, cheese, ice cream).
• “If you are not sure that dairy is pasteurised, do not eat or drink it.”

WHO says pasteurising milk, including milk used for cheese, is an important step in prevention. For people who work with animals, protective barriers and proper disposal of placenta, carcasses and organs matter. The CDC says animal workers should use gloves, goggles, protective clothing and masks.

If you use traditional or local dairy at home and want to know what can be done, ask your doctor. In the sources we read, the way to prevent infection is to pasteurise the milk; we cannot make promises about other ways of making local dairy safe.

What does treatment look like?

It is with antibiotics chosen by the doctor, usually a combination of several medicines. Treatment lasts weeks; the CDC gives at least 6 to 8 weeks. Full recovery can take from a few weeks to a few months. Do not stop the medicine without the doctor’s advice, because incomplete treatment raises the risk of the illness becoming chronic. Death from brucellosis is rare (the CDC: under 2 percent of those infected).

If you are pregnant, allergic to antibiotics or have a weak immune system, be sure to tell your doctor (CDC).

If your family ate the same dairy

Everyone who ate the same dairy or meat may have been exposed. Symptoms may appear weeks later. If they develop a fever, sweating, joint pain or a general feeling of illness, they should tell the doctor what they ate.

In short

Brucellosis can be prevented and treated. The main way to prevent it is pasteurised dairy and fully cooked meat. If you have a fever and joint pain and a history of unpasteurised dairy or contact with animals, tell your doctor. Diagnosis and treatment are for the doctor to decide.