The Problem
Water is increasingly being used for recreational activities as a boost to both mental and physical health. Furthermore, local economies benefit greatly from the tourism generated from such activities. However, microbial pollution from various sources such as sewage discharge and agricultural runoff pose a substantial risk to public health, with bathers more likely to show signs of gastrointestinal illness, respiratory, skin, ear and eye infections than non-bathers. In addition, there are clear relationships between weather and incidence of disease associated with Salmonella, Campylobacter, and Vibrio spp. Recent studies have shown that rising temperatures are causing a growing diversity of Vibrio bacteria in the sea that can harm shellfish and with concerns for human health.
Therefore, monitoring bathing water quality is vital to mitigate the health risks associated with recreational use of coastal and inland bathing waters and improve public perception and confidence in water quality.
Water quality is monitored for faecal pollution using faecal indicator bacteria (FIB), commonly, Escherichia coli (E. coli) and enterococci using culture-based methods. However, this method, requiring sample transportation to specialised laboratories, trained personnel and growth of the organism that takes 18–48h means any result obtained is retrospective delaying proactive measures to be taken concerning polluted waters. Considering that delays as short as 1-2 hours can result in pollution exposure with associated health risks, the need for significantly shorter lead times for obtaining accurate results is a critical bottleneck for assessing water quality in water supply infrastructures and recreational water bodies. Moreover, by focussing solely on FIB it is possible that other pathogens that may pose a risk to human health may go undetected. For example, over recent years additional pathogenic bacteria associated with human illness have been detected, including Salmonella species in bathing waters that had been classified as ‘good’ by current indicator detection methods.
The Solution
Building on its research expertise, Molendotech has developed novel technology to rapidly detect pathogens in water. The innovative technology allows near real-time assessment of bacterial contamination of water and overcomes the limitations of current culture-based approaches and allows rapid risk assessment of water quality. The team at Molendotech have developed two versions of portable near real-time assays: Bacteriskâ – can measure 10 samples simultaneously and Bactiquickâ – a smaller handheld version. Both types are designed to be used by non-specialist staff in situ.
Background
The technology that underpins Bacterisk and Bactiquick was translated from the biomedical research of the founder, Professor Simon Jackson. It uses molecules originally developed for the pharmaceutical industry and relies on an enzyme-based methodology, designed to swiftly identify and detect a molecular biomarker (lipopolysaccharide, also known as endotoxin) closely associated with Gram-negative bacteria (Figure 1). These bacteria types include faecal indicators such as E. coli but also notorious pathogens such as Salmonella, Campylobacter and Pseudomonas species, often found in contaminated water and posing significant health risks.
Figure 1. Endotoxin is a molecule in the outer membrane of Gram-negative bacteria. Our technology rapidly detects this molecule as a marker of bacterial contamination.
Our assay demonstrates a strong correlation with E. coli and coliforms, as detected by traditional culture methods. However, its capabilities extend beyond coliforms, allowing for the identification of a wide range of bacterial contaminants including pathogenic species not detected by current methods. Moreover, the assay protocol is designed to overcome effects of turbidity, pH, salinity etc and is thus suitable for a broad range of water samples.
