From science to action: finding a common European approach for tracking SARS-CoV-2 and its variants in wastewater (PEER)

Bernd knows that there are other requests from journalists in his inbox that he has not had the time to look at. He knows that there are messages from his colleagues that have also gone unanswered.

Over the past year, Bernd’s working hours went through the roof and all parts of his house – including the kitchen and the bathroom – turned into office space.

Coincidentally, both the kitchen and the bathroom are intrinsically linked to Bernd’s every-day occupation.

The chemical engineer has dedicated over two decades of his working life at the Commission’s Joint Research Centre (JRC) to urban water management.

Here, he has been studying the presence of chemicals, pharmaceuticals, antimicrobial agents and other veterinary medicinal products in urban wastewater, contributing to different EU Directives and strategies on water.

When the COVID-19 pandemic started and scientific articles about monitoring the presence of the virus using wastewater started popping up in various parts of the world, Bernd’s already busy work schedule took a hectic turn.

“The scientific evidence was mounting fast that wastewater could be part of the solution for tracking the spread of the virus, but the process of translating scientific evidence into practical policy measures is slow, and with COVID-19 there was no time for that”, Bernd explains.

“The JRC is here to advise policymakers, so I just knew that we had to jump into the driving seat to coordinate the scientific effort at EU-level, and help bring this evidence to the attention of those who were in charge of managing the pandemic, as fast as possible.”

The Commission Directorates-General for Environment (DG ENV) and Health and Food Safety (DG SANTE) were quickly on board, and a partnership was born to support the EU Member States in establishing wastewater surveillance systems to track the spread of SARS-CoV-2 and its variants.

What can wastewater tell about the spread of COVID-19?

“Not everyone is tested, but everyone uses the toilet”, Bernd says.

Which is why wastewater is an efficient – and cheap – tool to monitor the ‘health’ of the population in an urban area: it is a direct reflection of the human activities in a given area.

“It is a sort of a mirror which reveals the amount of chemicals, medicines and drugs used by the population and it can provide an indication of infections by bacteria or viruses among the population.”

The concept of wastewater monitoring is not anything new. Many countries were already using it to monitor the presence of chemicals, pollutants and contaminants in the environment. In the 1990s, wastewater surveillance was used to support the efforts to eradicate poliovirus.

So when the COVID-19 started, scientists in various parts of the world turned to wastewater as an easy solution to detect the presence of the virus in a city.

It quickly became clear that wastewater could reveal the presence of the virus and the infection dynamics earlier than the official testing figures.

One of the advantages is that wastewater can give an indication of the presence of the virus also in areas where there are people who are asymptomatic, who would normally not suspect having the virus and therefore not be tested.

Finding a common approach

What was missing was a common approach and a channel to pass on the results to the health authorities quickly, so that they could respond with timely measures.

“While some EU Member States already knew that this was a useful tool, some others did not have much experience with it. And it seemed that the scientists were talking with other scientists. We needed to find a way to get everyone on the same page and have the scientific community speak with the public health authorities and the operators of waste water treatment plants”, Bernd explains.

As a first step, Bernd’s team set up a Europe-wide knowledge exchange platform, which connected scientists, wastewater operators and public health authorities across Europe, and which enabled scientists to share the findings of their investigations as soon as they were ready.

Four virtual “Town Hall” events were organised in collaboration with the World Health Organisation (WHO), the United Nations Environment Programme (UNEP) and other national and international partners to facilitate the exchange of best practices and experiences.

“We can say that thanks to this initiative, the wastewater operators and the national public health authorities are now collaborating in places were that was not the case before.”

Europe-wide sampling

To support all partners across the EU, Bernd’s team orchestrated a Europe-wide wastewater sampling campaign, with the JRC taking care of the administrative and logistical organisation, as well as guidance on sampling procedures.

Containers were ordered by the JRC and distributed to 103 wastewater treatment plants around Europe.

“The sampling covered 103 cities and towns and provided a snapshot on the presence of the virus for a total of 31 million Europeans”, Bernd comments.

Wastewater was collected over a period of 24 hours from the local wastewater treatment plants, and the filled containers sent to a laboratory in the Netherlands, which carried out the analysis on the presence of the virus.

The containers were then sent to the JRC’s water monitoring laboratory in Ispra for chemical analysis and further characterisation.

The innovations stemming from this collaborative exercise enabled to screen large population groups to identify where more detailed analysis was needed.

“For instance, we identified a Polish city, where the official numbers of patients residing in the city did not correspond with the high viral load in the wastewater. After a more careful analysis, we were able to determine that the cause was the large number of commuters to the city”, Bernd says.

“This was a confirmation that wastewater surveillance could be used to see early warning signs, and that it provided additional information that was useful for better understanding the dynamics of the pandemic.”

The scientific team stresses that wastewater monitoring is a useful, complementary and independent approach to COVID-19 surveillance, but that it does not replace direct testing of the population.

“Wastewater surveillance is a tool to observe trends, but not an absolute means to draw conclusions about the prevalence of COVID-19 in the population.”

Commission recommendation

Following this initiative, and in the context of the launch of the HERA Incubator on 17 February 2021, the European Commission published in March 2021 a recommendation for EU Member States to put in place a national wastewater surveillance system targeted at data collection of SARS-CoV-2 and its variants in wastewaters.

Based on JRC advice, the recommendation sets out guidance for Member States on the design and management of SARS-CoV-2 wastewater surveillance systems, and the rapid transmission of the data collected to the competent health authorities.

A recent JRC report illustrates the resonant responses of the scientific community, which constituted the base for the possible creation of an EU-wide Wastewater Monitoring System for SARS-CoV-2 Surveillance.

“This was a massive collaboration effort. We would not have been able to do it without the enthusiasm of our partners within and outside the Commission, the effort of the operators at the wastewater treatment facilities, the support of various administrative teams across the JRC from procurement services to colleagues at the storage facilities, as well as the tireless work of my own team members”, Bernd concludes.