The prevalence of viral persistence in non-invasive biospecimens from individuals with PCS as measured by a variety of methods has also been low in previous studies [82,84–86], with the exception of two small studies that showed spike antigenemia in >60% of patients with PCS some of whom were also PCR-positive in plasma samples [87,88], and a study reporting S1 protein persistence in monocyte populations of patients with PCS up to 15 months post-infection [89]. The gene discussed is PSMD1; the disease is infection.