Sars CoV 2 test, molecular saliva sample as valid as a nasopharyngeal smear


Rome, December 13 – For the diagnosis of Sars Cov 2 infection “The validity of the saliva molecular sample is completely similar, 100%, to that of the nasopharyngeal smear. Indeed, it is better in the first days of infection. During the first six to seven days after infection, it is therefore helpful to use the saliva sample as the best tool for active infection control programs.anemic and for early diagnosis “.

To support it is Mario Plebani (in the picture), elected president of the European Federation of Laboratory Medicine, honorary professor of clinical biochemistry at the University of Padua and father of the molecular saliva test developed by the University of Venice. Plebanis, who was interviewed by the agency, explains it to AdnKronos Health and then emphasizes how the molecular saliva test has an ease of use in addition to its acceptance: “In schools and other programs it is acceptable in contrast to the nasal pharynx”.

In fact, the test simply involves chewing a piece of cotton extracted from a test tube into which it is then placed by the person performing the test. At the University of Padua “we have been using it for a year now, for all employees. Now the city hospital has replaced the pharyngeal nose with saliva in Covid staff monitoring, we are talking about doctors and nurses who no longer do the swab but the saliva analysis. In addition, this tool is the basis of the guard school program. “.

Also on the subject of saliva tests, news is coming from Singapore about the development of a potentially revolutionary Art technology (Antigen rapid test), which also aims to diagnose Covid. Using a proprietary kit amplification technique, a person’s saliva can be self-administered or tested for SARS CoV 2 at the point of care with sensitivity above current ART tests and close to that of Pcr (protein C test). reactive).

Call Parallel care point saliva rapid test enhancement (Passport, acronym), the technology produces results in minutes, without the need for additional equipment or specially trained staff. The invention was born out of a research collaboration between Duke-Nus Medical School, Singapore General Hospital (Sgh) and Singapore National Cancer Center (Nccs) – member institutes of the SingHealth Duke-Nus Academic Medical Center – and National University. of Singapore (Nus).

The test can be performed on the spot, allowing physicians to accurately diagnose Covid 19 and, in light of the imminent availability of oral antiviral drugs against Sars CoV2, to appropriately prescribe treatment, “shifting” Covid treatment, in the future, in the context of primary care. In addition, with the expected low cost and ease of use compared to PCR testing, Pasport could help Singapore and countries around the world diagnose Covid 19 early to begin proper case management. Research published in the journal Microchemistry Acta.


Unlike tests that use nasal or throat swabs, saliva-based ones are convenient and easier to administer on their own. Until now, however, saliva tests for Sars CoV 2 have not been considered reliable enough to be performed on a large scale. This is because the concentration of viral particles in saliva decreases dramatically after a person eats or drinks. As a result, saliva antigen tests are generally only reliable when done early in the morning, after an overnight fast, and before breakfast or brushing your teeth. This makes the analysis of saliva samples at other times of the day less reliable. The researchers corrected this problem using a two-step procedure. Like other ARTs, Pasport uses nanoparticles to bind the virus. But uniquely, it also adds a second type of nanoparticle that binds the first set of nanoparticles to amplify the signal. This makes Passport tests more sensitive to finding and reporting the virus and allows it to be used at any time of the day: its sensitivity is not compromised even after eating or drinking. Compared to other amplification techniques, Pasport is able to detect even at much lower viral loads, making it extremely sensitive. In a clinical study of more than 100 participants at Singapore General Hospital, Pasport’s sensitivity to the virus was 97% and its specificity was 90.6%, compared to the standard Pcrgold test.

“Our invention meets all expectations for an ideal fast test: easy saliva collection. is extremely accurate with very low false negative results, which largeor make it an invaluable control tool; can be performed at any time of the day, making it possible to use it at the point of care, with reliable certification “ points out Professor Soo Khee Chee of the SingHealth Duke-Nus Oncology Academic Clinical Program. ““With this, we hope that more people will take the test as a personal act of social responsibility before participating, in particular, in large-scale events or gatherings.”.

Duke-Nus and SingHealth have filed for copyright protection for the invention and entered into a licensing agreement with Digital Life Line Pte Ltd, a Singapore-based company.

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