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Facilitator: And welcome to all of you who have joined us for the frontline media briefing. I'm Olivia from the Australian Science Media Centre. Today's briefing is to announce that Australian researchers are developing an early warning surveillance system to track COVID-19 prevalence in the community.

Researchers from the University of Queensland and CSIRO have shown that they are able to detect the presence of the virus that causes COVID-19 in Aussie sewage. The principle concept study used wastewater samples from two wastewater treatment plants in South East Queensland which represents populations living in the Brisbane region. The researchers hope that this could be used to track COVID-19 prevalence in the community.

Joining us today are two speakers. The first is Professor Kevin Thomas, Director of the Queensland Alliance for Environmental Health Sciences at the University of Queensland.

Next we'll hear from Paul Bertsch, the Science Director of CSIRO Land and Water.

There will be an opportunity to ask questions of any of the speakers today at the end of the presentation. You can pop your questions into the Q&A box at the bottom right of your screen at any time during the presentation. Please make sure to use the Q&A box and not the chat box, which looks quite similar, but it goes elsewhere.

So we will begin now with Professor Kevin Thomas. Handing over to you Kevin.

Kevin: Thank you. And, thanks to everyone for attending this media briefing today on the release of our very exciting development in being able to advance the implementation of a wastewater based surveillance system for COVID-19.

So look, I'm guessing a lot of you must be wondering why sewage, and why ... or wastewater as we often call it as well? Well we know that the SARS COV-2 virus, the virus that causes COVID-19, are excreted from those infected with the virus, and through testing a community stool sample we can effectively test entire population. The entire population connected to a wastewater treatment works for example. So we ask the question, why only test individuals when you can also test an entire population?

How this works. Well the science of testing entire communities through wastewater is often called wastewater-based epidemiology and we do it a lot for things like illicit drugs and chemicals that people are exposed to in the community. But here we're looking at a virus instead of a chemical. And we collect samples at the last point before the wastewater influent is treated, and we do this really frequently, so we can collect small samples every few minutes. And what we're trying to do is to capture the toilet flushes that are coming from the community that are containing the stool samples that will be containing fragments of the virus that we're trying to detect. And once we have it, and we can see what's in those samples in terms of the SARS COV-2 virus, and that's why I'll hand you over to Paul who will explain the science behind on how we measure those wastewater samples.

Paul: Yeah. Thanks Kevin. And welcome everyone. The trick here is to isolate the RNA, RNA of course, is just an Alcaic acid that's found in all living cells, but for many viruses it's actually the genetic code. And so the idea is to isolate RNA that's specific to the SARS COV-2 virus, and two different methods were used to actually process. You can see the samples are collected, as Kevin mentioned, prior to going into the wastewater treatment plant. Two different methods were used to isolate the RNA and that's because we know still just learning about the virus, and so wanted to compare different methods side by side and this is happening globally really in real time.

The idea then is to extract the RNA. And once the RNA is extracted it then goes through a liquid handler and goes through what we call RRQPCR, and all that really is is a fancy term for a molecular photocopier, and what this allows us to do then is to photocopy the RNA, and it's a specific RNA fragment to the virus. And the scientist that you see in the middle is the lead of the CSIRO team, Dr Warish Ahmed, and he's still working quite laboriously on this project as we speak.

But the idea is to use these photocopies, photocopy many copies, and then a standard curve is generated. And really what that standard curve is is a CT on the axis is really Cycle Threshold, which really is just the number of photocopies you need to detect the RNA fragment from the virus above background. And you can see you get a nice standard curve there. The other thing that's done to be sure that we're amplifying the white fragment, the correct fragment from the virus is it's totally sequenced, and that's the little green check there, that is has been totally sequenced, and verified that it is the fragment from the virus.

What was found through this process was that for two different wastewater treatment plants, at two different points in time, there were positive tests for the RNA specific to the virus. And these two samples actually occurred close to what we know of as the peak in incidents, infection incidents in Queensland from at least those that had been tested. So again, you can see the sampling dates, and we get these two positive results suggesting that we're getting, we're able to detect the virus at low concentrations in this complex media, wastewater.

And back over to Kevin.

Kevin: So you're probably wondering why we'd want to test the entire community, and now we think some of the advantages and the benefits of also using wastewater testing alongside conventional testing is that it can tell us whether COVID has infected a community at a very early stage, and at the same time it can tell us, and help us inform us when a community is relatively free of COVID-19.

And if we can develop this approach into a technique that can tell us how much of the virus is in the wastewater then it has the potential to monitor the rate of infection all the time. So mirroring the result, the figure you say on the previous slide from Paul, where we saw the infection rates for South East Queensland, or for Queensland overall, we could do the same with specific wastewater catchments. And similarly we can then compare the community results to the results of the tested individuals from that catchment, and for example, work out if there are any common individuals are there who have COVID-19 but maybe don't have any symptoms. And we can, of course, monitor changes over time to evaluate whether the measures that we're all placed under at the moment to try to flatten the curve.

There are some caveats in how we think this technology should be used. We certainly don't think it should be used alone, it should be used as a complimentary technique to the existing testing that's being used. At the same time we really don't think they should take resources away from clinical testing, and I'm happy to say that our method as it's been developed isn't.

So what next for our team? Well the CSIRO and UQ team are really happy that we've been able to release this proof of concept study in a peer reviewed manner to the scientific community, and the general public, and it confirms that this is possible. And there is extensive capability across Australia in being able to deliver this type of technology, and there is certainly lots of interest in developing serious testing in Australia and overseas. And there are programs underway in various states and territories where people are at an early stage, and we hope that this proof of concept, and I guess as I said, the early release of the data will encourage others, and help others along this journey.

But I think to effectively manage a nationwide and planned use of the technology that we really need to develop a national coordinated collaboration to bring together all the groups that are working in this space to fully explore the clear benefits of what we believe a complimentary approach using wastewater can add to a surveillance of COVID-19 in the community. And then that's all from me. And I'm sure Paul and I are happy to take question.

Facilitator: Thanks though. Well there's now an opportunity for journalists to ask questions of the speakers. So questions can be asked by typing your question into the Q&A box on the bottom right of your screen. But please be sure to tell us where you're from as well. A reminder to use the Q&A box and not the similar looking chat box.

For those of you who have joined us over the phone we will give you the opportunity to ask questions as well, so we'll unmute you in a few minutes time. So we'll kick things off with the first question. So what level of population will this tell us about? Is it the suburbs, or just city level information?

Kevin: I can take that one if you like. It's Kevin here.

Facilitator: Yeah, sure. Go for it.

Kevin: Well at the moment what we do is, as I said, we take samples at the inlet to wastewater treatment works, so that would give you a catchment sewage work catchment sample, but there is clearly the potential to collect samples up the sewage network if that was what was desired in terms of the data that was needed. But that has added complications in that you have to go down manholes and quite often they're in the middle of roads, so they're not as easy to get hold of, good quality samples from a suburb level. So, there's already challenges with suburbs, but it's certainly feasible.

Facilitator: Excellent. Thank you.

Paul: And I might say...

Facilitator: And I've got a question. What?

Paul: I was just going to say I might add Olivia that one of the first groups that reported this was in the Netherlands, and they actually had positive samples from an area that had no confirmed cases. So it has been used very effectively as an early surveillance detection method.

Facilitator: Excellent. And I've got a question here from Tim Collett from Channel 10 Brisbane. Does the presence of COVID RNA in sewage have any implications for drinking water supplies?

Paul: I'm happy to take that one Kevin. It's a good question. But we ... drinking water is treated, and it's treated to get rid of all pathogens. This particular virus is extremely fragile as well, so it's unlikely that it would really live in wastewater for any time period, and certainly would not get into drinking water.

Facilitator: Fantastic. Thanks for that. And has there been a change ... oh this question is from Heather Catchpole from Refraction Media, has there been a change in the way university science is working together on research relevant to the pandemic?

Kevin: I can speak on behalf of the group of scientists that work on this project together, and we've been incredibly open. We've not sought any real kudos from doing what we're doing, it's just an open collaboration to try and contribute to the national and global effort in dealing with the COVID-19 pandemic. It's been purely of a collaborative and open motivation, and it's been absolutely fantastic. So maybe it is a change in how academic collaboration has happened, but it's been fantastic in the fact that over three weeks ago the group had never come together before, and three weeks later we have a peer reviewed publication that's hot in the press. It's quite an impressive achievement I think. But maybe it is a sign that academic collaboration has changed for the better.

Paul: Yeah. I'd like to just add to that one Olivia, especially since I wasn't part of the team that actually did the work and Kevin was, I just want to congratulate Kevin and the rest of the team for this unprecedented level of collaboration. We're seeing it's not only obviously here in Queensland, but all over Australia, and frankly all over the globe. And it's really advancing science at a pace that we've rarely seen in the past.

Facilitator: Fantastic. Thank you. And I have another question here from Stuart Layt from the Brisbane Times. What is the level of correlation with known testing results? Is there a suggestion there are more cases in the community than testing was picking up?

Kevin: Oh so...

Paul: Oh go ahead Kevin.

Kevin: We're really early stage here in terms of being able to measure SARS COV-2 in wastewater. And I think these early results tell us that the method is it's feasible. And the very rough comparison that we did suggests that the data that comes from testing and from the wastewater are comparable, but they're not sufficiently quantified at the moment to be able to make a direct comparison. So at the moment we're not quite there, but I'm sure that'll come in time.

Paul: And again let me just add Olivia that I think it is important to stress that this particular study is a proof of concept, and so as data emerges, and the methods get better, we expect that our ability to make such predictions will also improve. Having said that, there is a paper that's published out of MIT and Harvard, that does suggest significantly more cases in a suburb of Boston that was measured, so they measured less than 450 cases, 446 to be exact, and they were estimating between 23,000 and 155,000 individuals that were infected. That's a big range, because they're also in the early stages. And as we look at data that'll be emerging from China, Europe, and North America, we expect that these will be refined, will get better, we'll get much better at making those predictions.

Facilitator: Fantastic. Thanks for that. And another question from Stuart, we did mention it briefly [16:20], but maybe you could expand. He said, you mentioned this briefly but this ... is this type of broad scale detection being investigated anywhere else in the world?

Kevin: I can take that one if you like. It's being investigated, it's already being investigated in the Netherlands first of all, a few weeks back, and then colleagues in the US, and they're in multiple groups in the US applying this sort of technique. And there is huge interest from everywhere, and it was applied in China in the early days of the pandemic in Wuhan. And what we see as we addressed in the earlier question is that there is huge global interest, and there is a huge amount of sharing of data. There is ... there are kind of chat rooms available to share techniques and approaches so that we can advance this technology as quickly as possible. At the same time generate data that is comparable.

So I think in terms of global interest certainly there are ... in Europe there are a number of countries that are applying it, and the US, here, and I'm sure it will just develop as the approach becomes ... and the proof of concept study became more widely distributed so people can kind of make that early jump into being able to apply the technology as opposed to trying to develop the technology.

Facilitator: Excellent. Thanks for that. And, another question here from Tim at Channel 10. He's asking, post Corona should this testing be ongoing moving forward for early detection?

Paul: Kevin, you can take a shot at this too, but I think this is going to be really important for the recovery phase, because as the proof of concept is refined, and we get much better at being able to make predictions about community wide infections, this will be a way that we can manage our public health interventions going forward as we begin to recover and begin to relax, and actually monitor the infection rate as a function of interventions and relaxing a bit, interventions. So I think it's going to be a really, really important management tool.

Facilitator: Excellent. Thank you for that. And Stuart Layt would also like to know, how quickly could this be rolled out across Queensland and Australia?

Kevin: In terms of the capacity to do it, we already have a national wastewater drug monitoring program that collects wastewater every three months from a large percentage of the Australian population, and that's used for illicit drug monitoring, and this could easily build on that in terms of using the existing network of wastewater treatment works that provide samples to that collaborative effort. There are also other ongoing projects with organisations such as Water Research Australia, who have a strong link into the water industry and able to scale up the approach, and that's what really our desire and call for getting people together to do this in a collaborative manner is that it will allow the scale up across states and territories, and across the entire nation to be much quicker. It can be done reasonably quickly I believe, in terms of applying what we've learnt from our proof of concept, and building on existing collaborations and networks that are in place.

Facilitator: Thank you. And a question from Robert Stevenson here, what do you think about the use of your technology to predict the future for this fall?

Paul: Could you repeat the question, I didn't get the end of it either. Sorry.

Facilitator: Yeah, sure. No problems. I just realised there's another half to this as well elsewhere, so April is in the Southern Hemisphere and is equivalent to October in the Northern Hemisphere, the projections for the North diverge and probable progress in the fall, so yeah, she's asking, what do you think of your use of technology to predict the future for this fall?

Kevin: I don't think this is a predictive technology, it's a monitoring technology that tells us what's happening at a community level. And kind of extrapolating from that data I think we should be very cautious around, because all we're doing at the moment is being able to say whether it's present in a community or not, and hopefully the level that it is present the prevalence of infection within a community. I'm not quite sure of any predictive application that we could use at this stage.

Facilitator: No problem. Thanks for that. And just a question now of interest as well. So once genetic material is detectable in the water how widespread would you say the problem is? Like would that be indicative of one person being infected, or would there have to be say ten people, or is there like a baseline level for the number of people infected for it to be showing up in the water like this?

Paul: Yeah. I would say again that it's too premature to really know what that is. There's a lot of work that still needs to be done in terms of really understanding the lower level of detection, how much is actually being shared by an individual. You know a lot of these questions are being investigated in real time, so it's quite premature to make any speculation on what that number would be.

Facilitator: No problem. And could you use this on planes or boats coming into Australia to check for viruses in passengers?

Kevin: Potentially, yes. You could test the wastewater from planes or boats as you suggest, but kind of it takes time to do the testing. At the moment it takes a couple of days from collection to results, it's not an immediate answer of yes, no, whether that vessel would be ... would not have anyone who was carrying COVID-19 on board.

Facilitator: So there's still a little bit of a [22:56] there. So I do have some calling users at the moment, so what I'll do is we'll unmute you in a moment and so if you're a journalist calling in over the phone we'll unmute you when I say so, and you can ask your questions. So let's just hit unmute. Yes. So if you're a journalist calling in you can ask your questions now. No. And it sounds like there are no questions from our calling journalists. Excellent.

So it seems that's all the questions. So, thank you guys. That's it for today's event. Our full recording of today's presentations will be posted on [Symex] shortly.

For media requests with Professor Kevin Thomas please contact Danny Nash on 0434 551 578, or at For media requests with Dr Paul Bertsch please contact Helen Beringen on 0437 338 298 or at

Feel free to contact us direct at the Australian Science Media Centre is you do have any specific requests or questions on 08 7120 8666, or email

Thank you again to today's speakers, you've been fantastic. And thank you everyone for joining us for this online briefing.

Kevin: Thank you Olivia.

Paul: Thank you.

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