Mycobacterial Diseases
Open Access

Tuberculosis-Associated Mycobacterial Infections

Joanna Pia^{* *}Correspondence: Joanna Pia, Department of Microbiology and Immunology, University of Otago, Dunedin, New Zealand, Email:

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Description

Mycobacterial infections have long been a challenge to public health worldwide, with Tuberculosis (TB) being one of the oldest and deadliest infectious diseases known to humanity. Despite significant progress in combating TB, new mycobacterial infections, drug resistance, and co-infections continue to emerge, highlighting the need for ongoing research and a multifaceted approach to address these persistent health threats. In this article, we will explore the area of mycobacterial infections in the modern era, including the challenges they pose and the innovations catalyst progress in their prevention and treatment.

The resurgence of TB

Tuberculosis, caused by Mycobacterium tuberculosis, has been a constant companion of human civilization for thousands of years. In the mid-20th century, the development of antibiotics such as Isoniazid and Rifampicin led to significant advancements in TB treatment, reducing the disease's global burden. However, TB remains a major public health concern, particularly in regions with high prevalence and limited access to healthcare [1].

Key factors in the modern TB areas: The global HIV/AIDS pandemic has fueled the resurgence of TB. HIV weakens the immune system, making individuals more susceptible to TB infection and accelerating the progression from latent TB infection to active disease.

The emergence of drug-resistant TB strains, including Multi Drug-Resistant TB (MDR-TB) and Extensively Drug-Resistant TB (XDR-TB), has complicated treatment regimens and increased the risk of treatment failure.

TB disproportionately affects vulnerable populations, including those living in poverty, people in congregate settings (e.g., prisons), and refugees, highlighting the social determinants of TB [2].

Stigma surrounding TB remains a barrier to early diagnosis and treatment; as individuals may delay seeking care to avoid social isolation.

Advancements in TB prevention and treatment: The development and widespread use of molecular diagnostic tests like GeneXpert have revolutionized TB diagnosis, enabling rapid detection of M. tuberculosis and resistance to key drugs.

Novel drugs such as Bedaquiline and Delamanid have been introduced to treat drug-resistant TB, offering hope for patients with limited treatment options and improving treatment outcomes [3].

Research into new TB vaccines aims to enhance protection, particularly in adults, where the Bacillus Calmette-Guérin (BCG) vaccine's effectiveness is limited.

Emerging mycobacterial infections

While TB remains a formidable adversary, other mycobacterial infections are also gaining attention in the modern era. Two notable examples are leprosy and Non-Tuberculous Mycobacterial (NTM) infections.

Leprosy (Hansen’s disease): Leprosy, caused by Mycobacterium leprae, has been known since ancient times. Although it is no longer a major public health threat globally, pockets of endemic transmission still exist in some countries. Leprosy presents a range of clinical manifestations, from mild and localized to severe and disfiguring [4].

Early diagnosis and treatment with Multi Drug Therapy (MDT) have been effective in controlling the disease, but challenges remain in reaching remote and marginalized communities where leprosy persists.

Non-Tuberculous Mycobacterial (NTM) infections: NTM infections are caused by mycobacterial species other than M. tuberculosis or M. leprae. These infections primarily affect individuals with underlying lung conditions (e.g., chronic obstructive pulmonary disease) or compromised immune systems.

The prevalence of NTM infections has been rising in recent years. Diagnosis and management can be challenging due to the diversity of NTM species and their variable clinical presentations. Research into NTM infections and the development of effective treatments are ongoing.

Challenges and future directions

Drug-resistant TB: Addressing drug-resistant TB remains a priority. Ensuring access to novel drugs and shortening treatment regimens while maintaining high cure rates are essential goals.

TB-HIV co-infection: Integrated TB and HIV services, including universal testing and treatment for HIV, are important to addressing the dual burden of TB and HIV [5].

Prevention strategies: Expanding TB preventive therapy for individuals at high risk, including household contacts of TB patients and people living with HIV, can reduce the incidence of TB.

Research and innovation: Continued research into new TB drugs, diagnostics, and vaccines is necessary to improve TB control efforts.

Global collaboration: Collaboration among countries, international organizations, and stakeholders is vital to achieving global TB control targets and reducing the stigma associated with the disease.

Conclusion

Mycobacterial infections, particularly TB, have evolved and adapted in the modern era, presenting new challenges and opportunities for progress in their prevention and treatment. While TB remains a global health priority, emerging mycobacterial infections, drug resistance, and co-infections require sustained efforts and innovative strategies to mitigate their impact.

References

1. Monack DM, Mueller A, Falkow S. Persistent bacterial infections: The interface of the pathogen and the host immune system. Nat. Rev. Microbiol. 2004;2(9):747-765. [Google Scholar] [Pub Med] [Cross Ref]
2. Cohen KA, Abeel T, Manson McGuire A, Desjardins CA, Munsamy V, Shea TP, et al. Evolution of extensively drug-resistant tuberculosis over four decades: Whole genome sequencing and dating analysis of Mycobacterium tuberculosis isolates from KwaZulu-Natal. PLoS Med. 2015;12(9):e1001880. [Google Scholar] [Pub Med] [Cross Ref]
3. Winthrop KL, Iseman M. Bedfellows: Mycobacteria and rheumatoid arthritis in the era of biologic therapy. Nat. Rev. Rheumatol. 2013;9(9):524-531. [Google Scholar] [Pub Med] [Cross Ref]
4. Lawn SD, Badri M, Wood R. Tuberculosis among HIV-infected patients receiving HAART: Long term incidence and risk factors in a South African cohort. World J. AIDS. 2005;19(18):2109-2116. [Google Scholar] [Pub Med] [Cross Ref]
5. Delogu G, Sali M, Fadda G. The biology of Mycobacterium tuberculosis infection. Mediterr. J. Hematol. Infect. Dis. 2013;5(1). [Google Scholar] [Pub Med] [Cross Ref]