Breaking Transmission with Vaccines: The Case of Tuberculosis

Tuberculosis (TB) is the biggest killer of humanity. TB has killed more human beings than any other infectious disease in history, with an estimated loss of over a billion lives in the past 200 years (1). Despite effective treatment, in the WHO 2016 there were an estimated 10.4 million new TB cases and 1.8 million deaths attributed to the disease worldwide, surpassing those caused by AIDS (2). Still more worrying is the rising transmission of multidrug-resistant TB (MDR-TB), caused by mycobacteria that are resistant to treatment with at least two of the most powerful first-line anti-TB drugs, isoniazid and rifampin (2). Nearly half a million new MDR-TB cases are estimated every year, which together with increasing globalization makes TB an alarming global health problem (2). Loss of compliance with the current treatments for TB raises the frightening idea of a return to the pre-antibiotic era, when 50% of TB patients died in the absence of an effective treatment. Dissemination of multi- and extremely drug-resistant Mycobacterium tuberculosis strains has adverse implications for TB control in the 21st century.