Rapid Saliva Protein Test

Delivery Update:

Due to high demand, despatch may take up to 3 days at this time.  Shipping time varies by country. 

Rapid Saliva Protein Test (RSPT)


The RSPT is a non-invasive test indicating the immune response to infection from SARS-CoV-2, the virus underlying COVID-19:

– Provides results on the spot in 10 minutes
– Less intrusive than a swab or blood test
– Simple saliva sample required
– Can be taken on the premises (with a healthcare professional present)
– 94% accuracy in indicating the immune response to infection in patients with the absence of specific symptoms

It enables businesses with a healthcare professional present to test on a wide scale and build confidence to return to work quickly and safely.
The RSPT works by using a lateral flow device. Users provide a small saliva sample into a tube and add drops from Medusa 19’s novel solution which isolates and solubilises protein structures present in saliva, produced in response to SARS-CoV-2 infection.

This mixture is placed on the lateral flow device which migrates the saliva sample along the device. As the sample moves along the device, the antibodies to SARS-CoV-2 that are present in the saliva will attach to chemicals in the device, capturing them on test and control lines.

A colour change along these lines will appear depending on the presence of proteins (G for IgG and M for IgM).

The results are within 10 minutes

In the pack
1 x lateral flow cassette
1 x 3ml Buffer A
1 x 1ml Buffer B
1 x Cryotube
1 x Pipette
1 x IFU

The non-invasive test requires simple saliva collection, and is less intrusive than a blood sample, nasal or throat swab. Developed in the UK and Spain, the test indicates a user’s immune response to SARS-CoV-2, the virus underlying COVID-19.

Users provide a saliva sample into a collection tube, mixing this with a solution, which isolates and solubilises the protein structure present in saliva. This mixture is applied to a lateral flow device which migrates the saliva sample along the device. The test identifies antibodies unique to COVID-19, capturing them on test and control lines.

The RSPT isolates the protein complexes in saliva, allowing for recognition of saliva antibodies produced after the first contact with the virus, immunoglobulin M (IgM) and immunoglobulin G (IgG). Antibodies are produced when a virus is present as part of the body’s immune system response to infection.

At the early stage of infection, human cells produce an immune response and generate IgG, but more specifically IgM at the point of contact with the virus, which for COVID-19 is in the throat and respiratory tract. The antibodies are then transported from the lymph nodes into blood and saliva. In the early stage, detection in blood is not sensitive enough due to a high dilution effect, whereas in saliva, the independent clinical data indicates it is detectable.

The test is CE marked to 98/79/EC, registered with the MHRA, and is for use under supervision from a medical professional throughout Europe. It could prove pivotal in helping companies safely reopen workplaces and take action in line with government guidance.

Clinical trials were undertaken independently by Hospital Carlos III/Institute Carlos III – Hospital La PAZ, Madrid, on 254 participants in total. The study was conducted in multiple phases, comparing the test with PCR and blood antibody tests including a cohort with patients with no specific symptoms.

The Rapid Saliva Protein Test has been evaluated with samples of saliva. The results were compared to clinical diagnosis (based on RT-PCR, and clinical signs).

Relative specificity 92.5% (98/106), relative sensitivity 89% (132/148) and accuracy of 90.5% (230/254)

For patients’ with non-specific symptoms in the early phase (mean days post PCR of 3.3 days) relative specificity 92% (46/50), relative sensitivity 95.6% (44/46) and accuracy 93.7% (90/96).


A PDF of the instructions for use (IFU) can be found here:

Instructions for use – English