Although tuberculosis is relatively uncommon in the United States, it remains a potent killer in less developed regions. In South Africa, TB is the number one cause of death and there is a disproportionate share of HIV-associated tuberculosis. People with HIV are more likely to progress from latent tuberculosis to active tuberculosis disease, making prevention of tuberculosis transmission a priority.

A new study by investigators at the University of Liverpool’s Institute of Infection and Global Health, as well as colleagues in Africa, reveals that Mycobacterium tuberculosis carries a significant risk of mortality for patients with HIV and is often underdiagnosed. The study appeared in The Lancet.

Tuberculosis disease is a global killer, infecting 10 million people every year and taking the lives of 1.5 million. Being HIV positive is a risk factor for contracting tuberculosis disease and dying from it. Pregnancy also leaves women vulnerable to the ravages of tuberculosis, and pregnant women who also have HIV are especially at risk.

Tuberculosis (TB), in addition to causing symptoms such as coughing and fever, often results in significant weight loss and lack of appetite. In one study, more than 40% of Los Angeles residents with TB experienced a lack of appetite and more than 44% lost weight. This weight loss—also known as wasting—leads to malnutrition and subsequent impairment of the immune system, and puts the TB sufferer at a much higher risk of dying from the disease. Indeed, TB remains a top cause of death around the globe.