Research: the next epidemic could be spotted early in wastewater
Researchers analyzing wastewater say that routine monitoring at sewage treatment works could provide a powerful early warning system for the next flu or norovirus epidemic, alerting hospitals to prepare and providing public health agencies with vital health information, according to a press release by the University of Bath.
In the first large scale and comprehensive wastewater-based epidemiology (WBE) study in the United Kingdom, scientists at the University of Bath, Bangor University and the U.K. Heath Security Agency analyzed wastewater from 10 cities for both chemical and biological markers of health, including pesticides, pharmaceuticals and disease-causing viruses.
They collected samples from each location at hourly intervals over 24 hours on nine days in November 2021. The samples for each day were pooled before being processed and analyzed for trace chemical markers using mass spectrometry techniques.
The samples were also analyzed to detect any genetic material from viruses (SARS-CoV-2, norovirus and adenovirus). The total sampling catchment area equated to a population of around 7 million people.
Identifying disease outbreaks
The researchers detected localized outbreaks of norovirus, COVID-19 and flu, but could also correlate them with spikes in usage of over-the-counter painkillers such as paracetamol.
The results indicate that analyzing wastewater on a large scale in this way, dubbed wastewater-based epidemiology, could spot new outbreaks of diseases in communities early on, before large numbers were admitted into hospitals.
“Most people reach for the paracetamol when they first get sick, and try to treat their illnesses at home,” said professor Barbara Kasprzyk-Hordern, who led the chemistry work on the project. “So looking for large spikes in paracetamol use could give an early indication that there may be an infectious disease outbreak in the community.
“Norovirus and seasonal flu have always been a huge problem in hospitals each winter; now Covid-19 has added to this problem,” said professor Davey Jones, who led a team at Bangor University analyzing the wastewater for viruses. “Our proof-of-concept study has shown the potential for Wastewater Based Epidemiology to provide an early warning surveillance system for these and other diseases, which would enable hospitals to prepare for outbreaks in the local area.”
Detecting trace chemicals
Using highly sensitive chemical analysis that could distinguish between very similar markers, the researchers were able to tell whether pharmaceuticals had passed through the human body or had been directly disposed into the wastewater system.
They could also identify whether chemicals such as pesticides had been ingested through food or had washed into the wastewater system from agricultural land.
The team observed that differences in levels of chemical markers were mostly dependent on the size of population in the catchment area, however there were some outliers.
For example in one city, there was a much higher concentration of ibuprofen found in the water, compared with other cities, suggesting direct disposal from industrial waste.
The study is published in the Journal of Hazardous Materials.