Methods for Detecting Mycobacterial Mixed Strain Infections-A Systematic Review

Area of Science:

• Microbiology
• Infectious Diseases
• Epidemiology

Background:

• Mixed strain infections (MSIs) involve concurrent infection by multiple strains of a single pathogen species.
• MSIs are significant in mycobacterial diseases like tuberculosis and paratuberculosis, impacting transmission, evolution, and treatment.
• Understanding MSI prevalence and detection is crucial for both human and animal health.

Approach:

• A systematic review was conducted to define MSIs, assess their prevalence across hosts, and document detection methods.
• 121 articles reporting MSIs were identified, predominantly involving the *Mycobacterium tuberculosis* complex.
• Commonly used strain typing methods were reviewed, noting associated challenges and the need for standardization.

Key Points:

• MSIs are documented across diverse host species, with a focus on human tuberculosis.
• Strain typing methods for MSI detection vary, with some lacking the discriminatory power to differentiate true MSIs from microevolution.
• There is a need for standardized, highly discriminatory methods for accurate MSI identification.

Conclusions:

• Further research is required to investigate the prevalence of non-tuberculous mycobacteria (NTM) MSIs in humans and animals.
• Accurate identification and understanding MSI distribution will enhance knowledge of mycobacterial disease epidemiology and pathophysiology.
• Standardization of MSI detection methods is essential for reliable diagnostics and research.