Tuberculosis (TB) can be caused by more than one type of bacteria, one of which is Mycobacterium bovis. TB caused by M. bovis is of particular concern because of its predilection for children and the fact that infection can be acquired from animals and food. M. bovis is usually, but not exclusively, spread through consumption of unpasteurized, contaminated dairy products. The proportion of TB cases due to M. bovis in California has increased and the rate of M. bovis TB exceeds the national average. To identify risk factors associated with M. bovis TB in California, researchers reviewed surveillance records.

They found that M. Bovis TB in California has increased, exceeding the national average. They also found risk factors to be Hispanic ethnicity, extrapulmonary (outside the lungs) TB, diabetes, and other conditions that weaken the immune system (except for HIV/AIDS). Therefore, efforts to prevent M. bovis TB should focus on educating Hispanic populations and adults who have medical conditions that weaken the immune system about their risk. In addition, efforts to limit the demand and distribution of unpasteurized dairy products, which can also be associated with other foodborne diseases, should continue.

Epidemiology of Human Mycobacterium bovis Disease, California, USA, 2003-2011, Mark Gallivan, Neha Shah, Jennifer Flood, Emerging Infectious Diseases, DOI: 10.3201/eid2103.141539, published online 11 February 2015.