CRP and long COVID-19: In patients experiencing the post-acute sequelae of SARS-CoV-2 (PASC), or long COVID following the PASC, it was shown that immune system cells infiltrating lung tissue were associated with increased systemic inflammation and reduced lung function [16,17], and the overexpression of inflammatory biomarkers, including CRP and the neutrophil-to-lymphocyte ratio (NLR), was associated with subsequent lung function abnormalities in patients who recovered from COVID-19 [18].