“New technique detects respiratory viruses on used tissues, early detection for influenza and COVID-19”

During the pandemic, some parents competed in ingenuity to save their children from repeated tests, deemed too invasive. Like the diversion of baby flies, for example, which consisted of soaking the self-test swab in the mucus collected by the device rather than directly at the bottom of the little one’s nostrils. One method among others, not really validated by scientists.

And now we learn that Vincent Thibault, professor at the University of Rennes and head of the virology laboratory at the University Hospital of Rennes, has developed a technique for detecting “respiratory viral genomes on used tissues, using the equipment standard of medical analysis laboratories”, writes the University of Rennes in a recent press release.

Nursery and school

The idea germinated before the pandemic in the mind of this “admirer of the exploits of scientific police”. Professor Thibault’s postulate: “If today investigators manage to detect DNA fragments on samples that are several years old, why would it not be possible to detect respiratory virus genomes on used handkerchiefs, A few days ? “.

Especially since medical analysis laboratories, such as that of Professor Thibault at the University Hospital of Rennes, are now equipped with increasingly efficient machines. They are capable of carrying out automated molecular biology analyses, allowing the early detection of the main infectious diseases.

The doctor-researcher and his team therefore collected thousands of used tissues from the CHU crèche and primary school. This very fine and complete follow-up, week by week, of the circulation of the main respiratory viruses in children notably allowed “very early detection of the influenza epidemic, since the virus appeared in this crèche six weeks before the peak flu of 2019 is reached in metropolitan France”.

Detectable for months

To confirm these results, published in the journal Emerging Infectious Diseases, the team tested their method on around thirty volunteers with various respiratory symptoms. Among them, people infected with SARS-CoV-2, responsible for Covid-19. Contamination confirmed by means of the traditional swab inserted into the nose… and thanks to the used handkerchiefs that the patients had provided in parallel to the researchers.

“All the tissues made it possible to detect SARS-CoV-2, and for two thirds of them, in a more clear-cut way than by RT-PCR (reference technique for the detection of Covid, editor’s note)”. Better still: “The tissues tested were for some sent by mail, kept for several days and up to six months at room temperature: the viral genome remained detectable there”.

Even if this method has its limits (you have to blow your nose correctly, the work in the analysis laboratory is a little more important…), it is all the more promising since other teams have already validated the “general feasibility of this approach “. A hope no doubt shared by the children… and their parents. And a technique that is considerably more accessible and less expensive in terms of technicality.

Source: University of Rennes – April 2023