Wednesday, April 22, 2020

Parisian poo points the way forward

I refer to this, from Science:
By sampling sewage across greater Paris for more than 1 month, researchers have detected a rise and fall in novel coronavirus concentrations that correspond to the shape of the COVID-19 outbreak in the region, where a lockdown is now suppressing spread of the disease. Although several research groups have reported detecting coronavirus in wastewater, the researchers say the new study is the first to show that the technique can pick up a sharp rise in viral concentrations in sewage before cases explode in the clinic. That points to its potential as a cheap, noninvasive tool to warn against outbreaks, they say.
I wonder if it is sensitive enough a test if there is a flu catching on as well?  This method of testing for community spread of illness is better established than I knew, however:
 Another advantage of wastewater sampling is that it picks up virus associated with the vast number of people who are infected with SARS-CoV-2 but do not present symptoms for the disease, says Paul Bertsch, science director of land and water at the Commonwealth Scientific and Industrial Research Organisation in Australia. Although viral shedding varies among individuals and over the course of their infection, he says, a sewage system blends these variations into an average that represents the wider community. And depending on the sewage system, the warnings can come quickly. He points out that wastewater monitoring in Israel, for example, picked up a polio outbreak before any clinical cases appeared at all, according to a 2018 study.
Brisbane gets a mention in the next paragraph:
Building on similar studies in the Netherlands and the United States, Bertsch’s group last week reported the first detection of coronavirus in Australian sewage. He and his colleagues sampled wastewater in Brisbane representing 600,000 people, in March and April. In contrast to the study in Paris, they found a peak of viral shedding that corresponded to the peak detected through direct human testing. The difference might be explained by more prevalent human testing in Australia, he says.

Bertsch says he hopes to “tap into” Australia’s existing systems for monitoring wastewater for illegal drugs to develop a national COVID-19 monitoring system that could be in place within 1 month. Later, it might even be feasible to “go up-pipe” with specialized sampling portals allowing finer-scale community sampling. “We could test by postal code, for example,” he says.
Fascinating...

2 comments:

GMB said...

Great idea. But we should be using test like this for more nuance in our close-downs. We ought not be treating Broome in the same way we are treating Bondi.

GMB said...
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