Researchers in bid to improve detection of waterborne pathogens
13 August 2015
Research to test the ‘stickiness’ of hundreds of organic compounds might improve the detection of the microscopic water bugs that can cause vomiting and diarrhoea.
Two pathogens, Cryptosporidium and Giardia, are the focus of the research. The microscopic pathogens tend to enter water supplies from animal droppings and quickly cause outbreaks of illness that are characterised by diarrhoea and gastrointestinal illness.
Last week, Lancashire residents were warned to boil tap water, after tests at a water treatment plant discovered traces of Cryptosporidium, although the cause of contamination is not yet known.
Dr Helen Bridle of Heriot-Watt university is working in partnership with Dr Moushumi Ghosh from Thapar University, Punjab, to develop a new, ‘green’ compound that could be used to improve detection rates of such pathogens and improve water filtration in developing and developed countries.
In developing countries persistent diarrhoea caused by bugs such as these accounts for 30-50 percent of mortality of children under five. It is estimated that 250-300 million cases of cryptosporidiosis occur each year. In England, it’s estimated that around 60,000 cases go undiagnosed each year.
Pathogens like Cryptosporidium and Giardia can be infectious in very low doses, can live for months in water and are also resistant to chlorine.
“Currently tests to detect bugs like these are only 30 per cent effective. When water is monitored, the problem is that the bugs get stuck in the filters, says Dr Bridle. "This means they could go completely undetected. We’re looking for a naturally occurring polymer, or compound, that is ‘non stick’ and will repel the bugs and keep the filters from clogging up with them, to ensure they travel through the system and show up in results.”
The team is testing hundreds of natural polymers, which are chains of molecules, by printing them onto an array format. Initial testing will look at how the biopolymers interact with the pathogens and which features influence this, such as surface roughness, whether they repel water, pH conditions and exposure time.