The presence of heavy metals in the soil can make bacteria more resistant According to a new study done by researchers from the University of Georgia.
Resistance to antimicrobial agents is one of the most important global health problems. It refers to bacteria becoming resistant to antibiotics. Although the massive and sometimes inappropriate use of antibiotics contributes to this, other factors may also be responsible. A study published in Microbial Biotechnology shows that environmental pollution is also related to this phenomenon. According to researchers at the University of Georgia, soil pollution by heavy metals could contribute to antibiotic resistance.
Bacteria that are able to resist antibiotics
Scientists discovered that bacteria whose genes were associated with antibiotic resistance were found in high concentrations in heavy metal-rich soils in South Carolina. The bacteria Acidobacteria, Bradyrhizobium, and Streptomyces have genes that enable them to resist three molecules: polymyxin, vancomycin, and bacitracin. All three are used in the production of medicines for the treatment of infections. The bacteria also had multi-metal resistance genes to survive against arsenic, zinc, and cadmium.
The need to understand the evolution of bacteria
According to one of the authors of the study, Jesse C. Thomas, soil microorganisms develop new strategies to protect themselves. “The excessive use of antibiotics in the environment puts additional pressure on microorganisms and increases their ability to defend themselves against different types of molecules,” he explains. It is clear to him that agriculture or the burning of fossil fuels contributes to the resistance of bacteria to antibiotics. “We need a better understanding of how bacteria evolve over time,” he stresses, “this can affect our drinking water, food, and even our health.
A global threat
The World Health Organization (WHO) classifies antimicrobial resistance as one of the “greatest threats to global health, food security, and development”. This makes the treatment of certain infections such as tuberculosis or pneumonia difficult, as drugs are becoming less and less effective. The WHO recommends not to use too many antibiotics, and also to prevent infections by following hygiene rules such as hand washing and vaccinations.