spike protein covid
The first diagnostic designed to identify patients with Long Covid has received CE-IVD marking in Europe, meaning it is ready for its formal launch in countries accepting the designation this month. It works by looking for "patterns of inflammatory marker expression" in the blood, and in particular for the Covid spike protein persisting in white blood cells. Business Wire has the story.
The simple blood test can help to objectively diagnose patients suffering from Post-Acute Sequelae of COVID-19 (PASC), commonly known as Long Covid. Developed by IncellDx, the test will be available to prescribers and patients in September through one of the world's largest providers of diagnostic services.

A CE Mark indicates that the incellKINE Long Covid In Vitro Diagnostic fulfills the requirements of relevant European product directives and meets all the requirements of the relevant recognised European harmonised performance and safety standards...
The CE marking is supported by data from a validation study conducted by one of the world's largest providers of diagnostic services, showing the test provides greater than 90% accuracy across Covid strains. The test was developed based on clinical studies published in the peer reviewed journal Frontiers in Immunology, which showed that IncellDx researchers generated credible, objective disease scores for Long Covid using machine learning and artificial intelligence to measure and analyse sets of inflammatory markers called cytokines and chemokines. The studies also demonstrated that patients with previous COVID-19 infection and lingering symptoms were found to have a distinct immunologic profile characterised by patterns of inflammatory marker expression. In a subsequent publication, IncellDx found SARS CoV-2 S1 spike protein in monocytic reservoirs of Long Covid patients up to 15 months after acute infection. These papers can be found here and here.

Patterson added, "Long Covid presents a significant diagnostic and treatment challenge for patients. Many of the symptoms that are associated with long Covid, including fatigue, brain fog, shortness of breath, insomnia, and a wide range of cardiovascular issues, can easily be mistaken for other conditions like post-Lyme, ME-CFS, Fibromyalgia, or even the common cold. Having an effective - and importantly an objective - tool to diagnose the condition is absolutely essential. An objective test that can detect immune signatures specific to Long Covid is vital for effective diagnosis and to enable patients to seek effective treatment."
Patients who have or think they may have Long Covid can learn more and register for a test here.

One question is how it will distinguish Long Covid from 'Long Vaccine'. The same research team behind this test also investigated whether vaccination produced a similar syndrome characterised by lingering spike protein, immune inflammation and the typical symptoms. They found it did: spike protein persistence from vaccination appeared, they said, to be a "major contributor" of symptoms similar to Long Covid post-vaccination. Further, given that the spike protein "alone delivered by vaccination can cause similar pathologic features", they concluded it may be a "major contributor" of Long Covid symptoms post-infection as well. In other words, Long Covid after infection may be being caused or prolonged by spike protein from the vaccine rather than the infection. It's not clear if the new diagnostic test will distinguish between these causes (or if that's possible).