Mycobacterial Diseases
Open Access

Wastewater Surveillance for Tuberculosis Detection

Faizal Metwa^{* *}Correspondence: Faizal Metwa, Division of Infectious Diseases, University of Virginia, Charlottesville, USA, Email:

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Description

Tuberculosis (TB), remains one of the leading infectious diseases globally, particularly in low- and middle-income countries. Traditional surveillance methods often rely on clinical diagnostics and patient reporting, which can be slow and limited in scope. Molecular surveillance of TB-causing mycobacteria in wastewater presents a novel approach to monitor the spread and prevalence of TB in communities. This method leverages advanced molecular techniques to detect and analyze Mtb DNA in wastewater, providing a complementary tool for public health surveillance. Wastewater-Based Epidemiology (WBE) has emerged as a powerful tool for monitoring public health. By analyzing wastewater, researchers can detect the presence of pathogens, pharmaceuticals, and other biomarkers that reflect the health status of a community. For TB, wastewater surveillance offers several advantages, such as, sampling wastewater is less invasive and more cost-effective than collecting clinical samples from individuals. Wastewater reflects the health status of entire communities, including individuals who may not seek medical care. Molecular surveillance can detect TB-causing mycobacteria before symptoms appear widely in the population, potentially enabling earlier intervention.

Molecular techniques for detecting mycobacteria in wastewater

The detection of TB-causing mycobacteria in wastewater involves several molecular techniques:

Sample Collection and Preparation: Wastewater samples are collected from sewage systems, treatment plants, or specific locations within a community. Samples are then processed to concentrate bacterial cells and extract DNA.

Polymerase Chain Reaction (PCR): PCR is a widely used technique for amplifying specific DNA sequences. In wastewater surveillance, PCR targets specific genetic markers unique to Mtb, such as the IS6110 insertion element or the 16S rRNA gene.

Quantitative PCR (qPCR): qPCR not only detects the presence of Mtb DNA but also quantifies the amount, providing an estimate of bacterial load in the wastewater.

Next-Generation Sequencing (NGS): NGS allows for comprehensive analysis of the microbial community in wastewater. It can identify and characterize Mtb strains, detect genetic mutations associated with drug resistance, and provide insights into the epidemiology of TB.

Public health implications

Wastewater surveillance can serve as an early warning system, alerting health authorities to increases in TB prevalence or the emergence of drug-resistant strains. By identifying hotspots of TB transmission, public health officials can target interventions, such as screening, treatment, and community education, more effectively. Wastewater surveillance complements traditional clinical data, providing a more comprehensive picture of TB epidemiology and helping to identify underreported or undiagnosed cases. Wastewater contains a complex mixture of organic and inorganic substances, which can inhibit PCR and other molecular assays. Effective sample preparation and DNA extraction methods are critical. Ensuring that molecular assays are both sensitive (able to detect low levels of Mtb) and specific (able to distinguish Mtb from other mycobacteria) is essential for accurate surveillance. Interpreting the presence and concentration of Mtb DNA in wastewater requires careful consideration of various factors, including population size, sewage system design, and environmental conditions.

Conclusion

Molecular surveillance of tuberculosis-causing mycobacteria in wastewater represents a promising approach to enhance TB monitoring and control efforts. By leveraging advanced molecular techniques, this method provides a non-invasive, costeffective, and community-wide tool for detecting and quantifying Mtb in the environment. While challenges remain, continued research and development in this field have the potential to significantly improve our ability to track and combat TB, ultimately contributing to better public health outcomes.