A diagnostic kit to detect the new coronavirus that can be employed directly by basic health units, providing a result in up to 45 minutes, at a low cost and with high accuracy. The innovation, which may help fight Covid-19, has had its patent deposited after a year of work by researchers of the Oswaldo Cruz Institute (IOC/Fiocruz), the Federal University of Santa Catarina (UFSC), and the Federal Institute of Santa Catarina (IFSC), in a partnership with the company SPK Solutions.

Simple, quick and cheap, this diagnostic kit identifies the genetic material of the Sars-CoV-2 using a technique called RT-LAMP. In validation tests with more than one thousand samples, the test has proven to be as accurate as RT-PCR, considered the gold standard for the diagnostic of Covid-19. For oropharyngeal samples, collected with a swab introduced in the patient’s nose, the test showed 96% sensitivity and 98% specificity.

“What makes this kit stand out is the fact that it integrates all the steps of the molecular diagnosis, with a methodology suitable for the point of care. This is a simple, cheap and robust method that makes it possible to make a diagnosis exactly where it is needed”, emphasizes André Pitaluga, IOC researcher and project coordinator.

The methodology can also be used for samples of saliva, which is easier to collect. In that case, the first analysis show a 70% sensivity and a 98% specificity, and a new round of tests shows that it is possible to achieve almost 100% sensitivity if the sample is collected during fast, right after waking up.

“Eating, drinking or brushing one’s teeth can alter the composition of saliva and may therefore reduce the presence of viral particles in the sample, making a diagnosis harder. Tests made with the sample collected while fasting, in the morning, are still ongoing, but preliminary results are very encouraging so far”, comments the researcher.

To develop this diagnostic kit, researchers relied on the support of the IOC’s Nucleus of Technological Innovation (NIT-IOC, acronym in portuguese) and on the financial support of the company Engie, of the Inova Fiocruz Program, and of the Public Ministry of Labor (MPT, acronym in portuguese). Validation tests were carried out in a partnership with the Central Laboratory of Public Health of the state of Santa Catarina (Lacen-SC) and the municipalities of Tubarão and Florianópolis.

Particularities

The estimated cost of the new Sars-CoV-2 diagnostic kit is R$ 30, less than one third of the price of a RT-PCR kit, which costs approximately R$ 100. The operation costs to carry out the test is also significantly lower, considering the equipment and labor involved.

The reearchers highlight that the tool uses components for the extraction and amplification of viral RNA. The first step aims to extract from the sample only the genetic material, leaving other molecules aside. The goal of the second step is to identify and multiply targets of the Sars-CoV-2 genome, to make its detection possible.

Source: Fiocruz site.