Tuberculosis ( TB ) is one of the epidemic diseases caused by Mycobacterium tuberculosis, which threatens global public health. Tuberculosis usually affects the lungs but can also affect other parts of the body. Tuberculosis has been a deadly disease of humanity since ancient times and has always threatened public health leading to morbidity and mortality. In 1993, the global TB epidemic led the “World Health Organization” to declare TB a high priority issue.
The antibiotic resistance’s increase in patients since the 1970s, increasing human immunodeficiency virus (HIV) infection, and resulting immunosuppression since the 1980s have increased the incidence of TB. According to the “Global Tuberculosis Report 2021” of the World Health Organization (WHO), it has been reported that approximately 10 million people have TB disease, and about 6.8 million people have been newly diagnosed with tuberculosis. The WHO’s most recent 2019 global death estimate showed that TB is the most significant cause of death from a single infectious agent and is the 13th leading cause of death worldwide. In 2020, TB was expected to be the second leading cause of death, after COVID-19, from a single infectious agent.
Barriers to controlling TB infection include long treatment regimens of 6 to 9 months, drug resistance, the absence of a highly effective vaccine, and a poor understanding of the factors that control infectivity and disease progression. Only 10% of individuals infected with M. tuberculosis develop active disease. Immune responses associated with TB susceptibility or resistance are unknown. Several studies have suggested that host genetic factors influence susceptibility and resistance to TB. TB-associated genes were identified in the OMIM database: NRAMP1, SP110, CISH, TLR2, IRGM, IFNGR1, TIRAP, IFNG, CCL2, CD209 (Table Below). Genetic counseling is recommended for those with more than one TB diagnosis family history.