General Overview of Nontuberculous Mycobacteria Opportunistic Pathogens:Mycobacterium aviumandMycobacterium abscessus

Nontuberculous mycobacteria (NTM) are emerging human pathogens, causing a wide range of clinical diseases affecting individuals who are immunocompromised and who have underlying health conditions. NTM are ubiquitous in the environment, with certain species causing opportunistic infection in humans, includingMycobacterium aviumandMycobacterium abscessus. The incidence and prevalence of NTM infections are rising globally, especially in developed countries with declining incidence rates ofM. tuberculosisinfection.Mycobacterium avium, a slow-growing mycobacterium, is associated withMycobacterium aviumcomplex (MAC) infections that can cause chronic pulmonary disease, disseminated disease, as well as lymphadenitis.M. abscessusinfections are considered one of the most antibiotic-resistant mycobacteria and are associated with pulmonary disease, especially cystic fibrosis, as well as contaminated traumatic skin wounds, postsurgical soft tissue infections, and healthcare-associated infections (HAI). Clinical manifestations of diseases depend on the interaction of the host's immune response and the specific mycobacterial species. This review will give a general overview of the general characteristics, vulnerable populations most at risk, pathogenesis, treatment, and prevention for infections caused byMycobacterium avium, in the context of MAC, andM. abscessus.