Antibiotic resistant bacteria can be carried by rivers and streams, a new study reveals, and are very common in areas where wastewater facilities are located.
Researchers believe the wastewater locations may be the source of at least half of resistant bacteria found in microbes. The study focused on the Thames River in England.
University of Exeter Medical School researchers, along with investigators from the University of Warwick's School of Life Sciences, say enterobacteriaceae bacteria, often found in human digestive systems, was discovered near treatment plants along the river.
Antibiotic resistance is a growing problem in the healthcare industry, explain the researchers.
"Antibiotic resistance naturally occurs in the environment, but we don't yet know how human and agricultural waste is affecting its development. We've found that wastewater discharges effect resistance levels and that improvements in our treatment processes could hold the key to reducing the prevalence of resistant bacteria in the environment," Elizabeth Wellington of the University of Warwick said.
Other chemicals found near the treatment facilities could offer clues to how this resistant bacteria could be spread by the water treatment plants. Researchers examined samples of sediment and water collected from 13 locations near the Thames River.
"[This new study] has allowed us to uncover an association between a number of compounds - such as zinc, phosphorous and silicon - and antibiotic resistance. We think those bacteria that have developed to survive in environments rich in metals may also possess antibiotic resistance mechanisms - highlighting the complexity of this global issue." William Gaze of the University of Exeter Medical School said.
Rainfall patterns also seem to play a role in the spread of resistant bacteria. When rain happens in forested areas, the spread of the organisms is reduced. When precipitation occurs over grasslands, concentrations were found to increase.
A model of the distribution of bacteria in the environment was developed by the study researchers. That model could assist researchers in predicting antibiotic resistance in areas without the need to examine water samples.
A form of Staphylococcus aureus, which causes Staph infections, was the first bacteria to develop a resistance to antibiotics and first noticed in 1947. This was just three years after the development of penicillin, the first major recognized antibiotic.
The study researchers believe that antibiotic-resistant bacteria from around wastewater treatment plants could enter human bodies, although effect on public health remains unknown.
The discovery and analysis of antibiotic-resistant bacteria around wastewater plants was detailed in The ISME Journal.
