Low-cost Test Detects Delta Variant in Saliva

The most accurate COVID-19 tests require laboratory equipment and technical skills to determine results. This limits the speed of COVID-19 test, track and trace systems, making it more difficult to slow the spread of the disease. Laboratories also have to genetically sequence samples to test for specific variants, which takes even more time and resources. While at-home tests exist, many require self-collection and mailing to a central laboratory. Others are similar to rapid antigen tests, which have a high potential for false-negative and false-positive results. Moreover, these tests do not detect different variants of COVID-19.

Variants of the SARS-CoV-2 virus may have different transmission rates, require different treatments, and respond differently to vaccines. Scientists from Harvard University and the Massachusetts Institute of Technology (MIT), both in Cambridge, MA, and several Boston-area hospitals, recently created miSHERLOCK, an inexpensive, CRISPR-based diagnostic test that allows users to self-test for variants of SARS-CoV-2 at home, using their saliva.

Simple things that used to be ubiquitous in the hospital, like nasopharyngeal swabs, were suddenly hard to get, so routine sample processing procedures were disrupted, which is a big problem in a pandemic setting,” said co-first author of the study, Dr. Rose Lee, who is a visiting fellow at the Wyss Institute for Biologically Inspired Engineering at MIT.

Our team’s motivation for this project was to eliminate these bottlenecks and provide accurate diagnostics for COVID-19 with less reliance on global supply chains, and could also accurately detect the variants that were starting to emerge,” she notes.

miSHERLOCK is a low-cost point-of-care [COVID-19] test that is capable of detecting and differentiating specific SARS-CoV-2 variants, which could be used to guide patient care as well as for infection control or epidemiological purposes,” lead author Helena de Puig Guixe, a postdoctoral researcher at the Collins lab at the Wyss Institute for Biologically Inspired Engineering, told Medical News Today.

Our device is low-cost, provides a simple visual answer in 1 hour, and only requires saliva from a patient with no additional equipment separate from the device itself (including its standard battery). […] Our full device, including all testing components, costs $15, down to $6 with reuse of the housing and electronics, but could be as low as $2–3 per test if produced at scale,” she added.

Source: https://www.medicalnewstoday.com/