Severe headache after consuming raw milk? Test for brucellosis

Humans should avoid drinking raw milk and unpasteurised milk products. [iStockphoto]

Many milk consumers are not aware of brucellosis, a disease mainly caused by the consumption of unboiled raw milk and other dairy products and eating undercooked meat and meat products.

Dr Mulei Muema, an epidemiologist, at Washington State University Global Health-Kenya and a PhD Fellow, at the Centre for Epidemiological Modelling and Analysis, University of Nairobi explains that brucellosis is a zoonotic disease (transmitted from animals to humans) caused by a bacterium from the genus Brucella that affects livestock, wildlife, and humans.

He says that brucellosis is found worldwide but is particularly common in regions where livestock keeping is practised, especially in pastoral communities.

Dr Muema says that apart from the consumption of raw and unboiled meat, brucellosis can be caused by poor handling and disposal of livestock afterbirths, animal carcasses, and internal organs at slaughter leading to environmental contamination and increased risk of infection in livestock and further spread to the human population.

Symptoms of brucellosis in humans can vary but often include flu-like symptoms such as fever, chills, fatigue, sweating, muscle and joint pain, and headaches. If left untreated, brucellosis can cause severe complications to organs and to the bones and joints.

"It's important to note that the symptoms of brucellosis can be non-specific and mimic those of many other infectious diseases, making diagnosis challenging," explains Muema.

Preventing brucellosis involves a combination of measures to reduce the risk of infection in humans and animals. "Boiling milk for direct human consumption is one of the most essential methods in preventing transmission of the disease from animals to humans. Humans should avoid drinking raw milk and unpasteurised milk products or coming in contact with aborted animal fetuses," says Muema.

Other strategies to prevent human infection include risk communication and community engagement through education campaigns that raise awareness and improve food safety and occupational hygiene.

Targeted livestock vaccination can prevent brucellosis. Other prevention methods include isolating all aborted animals until all discharges have stopped, burning, or burying all contaminated materials such as fetuses, and fetal membranes.

"It's essential to clean and disinfect cattle premises contaminated with fetuses and fetal membranes," says Muema.

According to the expert, brucellosis is associated with enormous socioeconomic and public health impacts. For example, it causes a significant burden on human health due to costs incurred in diagnosis and treatment, loss of person-hours, and hence loss of income. Nonetheless, it leads to production and reproductive losses due to abortions, stillbirths, infertility, reduced milk yields, and trade restrictions, leading to significant economic and household income losses.

"For effective control of brucellosis, there is a need for multisectoral coordination, bringing together key players in livestock health, public health, food safety and hygiene, and community education and sensitization," he observes.