What Clues to the Covid-19 Epidemic Lie in Monaco’s Waste-Water?

Did you know that there are back-up ways to test for the presence of Covid-19 in communities other than individual testing. Researchers have been investigating if waste residue such as in the sewer system would yield traces of the virus and if that would give clues as to the rate of infection. The answer is that there are indeed traces of the virus. 

Fortunately they are not at levels that are dangerous to those researching it. They are non- contaminating and inactive. And it is also true that the levels of the virus found in the sewer system sometimes (but not always) is linked to the level of infection in a community. 

Monaco since last October as well as France and Italy have been investigating their waste water to see if this may help interpret how the epidemic is penetrating their populations. Monaco already has in place a very strong test program for Covid in individuals. 

Link between Individual and Group Testing 

Is there a correlation between the evidence from individual testing and group testing from sewage systems? Reportedly in France (in the Obepine Project) researchers have shown a correlation between the presence of the virus in sewage and the number of cases of Covid-19. 

Similar reporting reveals Monaco also has been able to correlate the presence of the virus in wastewater with the number of positive tests per 100,000 inhabitants. During the Festive period there was a significant increase noted in the presence of the virus in wastewater which has since receded. But this same drop-off has not yet reportedly been observed in individuals tested using PCR and antigenic tests. So for the moment this is an intriguing but imprecise science.

High Incidence Rate in January

Before the festive period the incidence of Covid in Monaco was substantially below Nice but has since elevated to 386.84 in the week ending January 10th. This is getting closer to that of Nice which is at 387.8 (Public Health France). But Monaco’s robust health program tests about three times as many people proportionately – over 12,000 people per 100,000 inhabitants against over 4,000 for Nice

Group Testing Locations in Monaco

Early days yet in this science, yet Monaco is taking it seriously in the event it eventually gives additional insight into the waves of the epidemic. 

The main testing location is interestingly near the Port and Rue Quarantine whose history ironically goes back to the deadly Black Death plague itself. There is a major sewer access there from which samples are taken. Press reports also mention up to eleven locations for sampling : Rainier-III / Rue Bosio junction; Roundabout on avenue des Moulins and avenue de la Madone; Église des Carmes; Avenue Princesse Grace in two separate locations; Wurhemberg storm basin; pre-treatment station: arrivals from Monaco-Ville, Fontvieille and Boulevard Albert-Ier; Fontvieille station; Boulevard d’Italie. Each location may yield indicators of the progress of the pandemic in the surrounding thousands of individuals. 

All the Way to Denmark for Analysis 

The samples are sent to the Eurofins laboratory in Denmark after being stored in a cooler at 4°C. To quantify the presence of the virus, scientists use an analysis technique called “RT-PCR” similar to the PCR nasal swab test for individuals. 

Test, Trace and Isolate 

Test trace and isolate is one of the main weapons against the spread of Covid and the testing options are now taking more forms including testing the whole community via its waste-water.