Further examples of water surveillance
Activity: Further examples of water surveillance
Extended learning example 1: Drinking water monitoring in Ireland
The following extract summarises a study of AMR in drinking water from private wells in Ireland (Alawi et al., 2024). Read the extract and then answer the questions below.
In Europe, data on AMR in drinking water is scarce. In Ireland, as in many countries, household drinking water is supplied via mains, private wells or water schemes. We identified Irish private drinking water supplies as reservoirs of antimicrobial resistant bacteria (ARB), including both Gram-negative (n = 464) and Gram-positive (n = 72). For example, we isolated linezolid-resistant Enterococcus. Linezolid is a last-resort antibiotic used to treat vancomycin-resistant Enterococcus sp (VRE). Our work suggests that private drinking water is a potential sink and source of AMR pathogens.
This highlights a value of drinking water surveillance as the surveillance would provide information regarding the movement and persistence of ARB and ARGs that are able to survive in drinking water and subsequently have the opportunity to be mobilised through humans.
- What environmental compartment was studied?
- What was the main finding of the study?
Answer
- The environmental compartment was drinking water from private wells.
- The study found a significant level of contamination and AMR bacteria in the drinking water wells, showing possible contamination of private wells by human or animal faeces.
Extended learning example 2: Surveillance of antibiotics in wastewater in South Africa
Wastewater surveillance is used for monitoring resistant bacteria. It can also be used to generate information on antibiotic use in situations where there is limited data on quantities of antibiotics used.
A study in South Africa tested different antibiotics and their degradation products in wastewater from a WWTP and from an informal settlement, finding that the quantities of specific antibiotics measured in sewage exceeded the quantities that were expected based on existing prescription data (Holton et al., 2023). Incomplete data on prescriptions was put forward as one of the reasons for this difference, as well as other methodological difficulties such as estimates of the population size contributing to the wastewater samples and stability of the residues analysed.
Can you suggest another reason for the disparity?
Answer
It is also possible that antibiotics are purchased and used without prescriptions.
When you’ve tried this activity you should return to Section 7.2 of the course.
Wastewater treatment (part 2)
