Antimicrobial resistance is the ability of disease-causing microorganisms to withstand treatments such as antibiotics. Often described as a silent pandemic, it is already responsible for an estimated 1.27 million deaths each year, with the highest burden in Africa. Efforts to address antibiotic resistance have largely focused on hospitals and clinics. However, resistant bacteria and resistance genes can also spread through wastewater and the environment. Wastewater treatment plants reduce bacterial loads, but there is a blind spot.
Researchers working through the African Microbiome Project analysed wastewater from several treatment plants in the City of Tshwane. They found that extracellular DNA carrying antimicrobial resistance genes remained in water released into the environment after standard treatment. Extracellular DNA is genetic material released when bacterial cells break apart. Some microorganisms can incorporate this material into their own DNA, allowing resistance to spread even when the original bacteria are no longer present.
Some of the genes detected were linked to resistance against antibiotics of last resort. The findings do not mean that treated wastewater directly causes disease, but they identify a pathway through which resistance may survive treatment and potentially re-enter communities through drinking water, food production or recreational exposure.
The researchers argue that antibiotic resistance must be understood as both a medical and environmental issue. Monitoring systems should include genetic material, wastewater technologies may need to incorporate treatments, and stronger collaboration is needed among policymakers, engineers, microbiologists and public health practitioners. _________________________________________________________________________________________________________
The article can be accessed on: Phys.org
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