A Review of Persistent Post-COVID Syndrome (PPCS)

Abstract

Persistent post-COVID syndrome, also referred to as long COVID , is a pathologic entity, which involves persistent physical, medical, and cognitive sequelae following COVID-19, including persistent immunosuppression as well as pulmonary, cardiac, and vascular fibrosis. Pathologic fibrosis of organs and vasculature leads to increased mortality and severely worsened quality of life. Inhibiting transforming growth factor beta (TGF-β), an immuno- and a fibrosis modulator, may attenuate these post-COVID sequelae. Current preclinical and clinical efforts are centered on the mechanisms and manifestations of COVID-19 and its presymptomatic and prodromal periods; by comparison, the postdrome, which occurs in the aftermath of COVID-19, which we refer to as persistent post-COVID-syndrome, has received little attention. Potential long-term effects from post-COVID syndrome will assume increasing importance as a surge of treated patients are discharged from the hospital, placing a burden on healthcare systems, patients’ families, and society in general to care for these medically devastated COVID-19 survivors. This review explores underlying mechanisms and possible manifestations of persistent post-COVID syndrome, and presents a framework of strategies for the diagnosis and management of patients with suspected or confirmed persistent post-COVID syndrome.

Long COVID and Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS)—A Systemic Review and Comparison of Clinical Presentation and Symptomatology

“…A particular phenotype of ME/CFS has been termed post-infectious fatigue syndrome, and it has been linked to acute viral infections such as Epstein-Barr virus (EBV) and human parvovirus (HPV)-B19 [74,75]. While the etiology of long COVID is likely multifaceted and the research is still ongoing, it has been similarly linked to inflammatory state and dysregulated immune response [76,77], further underlying the resemblance between long COVID and ME/CFS [78].…”

Long-COVID Syndrome? A Study on the Persistence of Neurological, Psychological and Physiological Symptoms

“…Emerging aspects of COVID-19 clinical presentation are the long-term effects, which, in the absence of any formally agreed definitions, characterize the so-called “ long-COVID ” or “ long-haul COVID ” described in recent international journals [ 20 , 21 , 22 ].…”

The post-acute phase of SARS-CoV-2 infection in two macaques species is associated with signs of ongoing virus replication and pathology in pulmonary and extrapulmonary tissues

“…This finding in a recognized NHP model for COVID-19 research is of particular interest because of the growing concern for long-COVID in humans [70]. More than a year after the start of the pandemic, it is evident that humans can suffer from COVID-19-related symptoms, weeks to months after seemingly resolving the infection [5-7].…”

“…Then, a convalescent phase is initiated during which the infection resolves, and patients recover from the disease. Nevertheless, evidence is accumulating for the existence of an enlengthened recovery process, even for non-hospitalized patients [5-7]. Moreover, in this phase, chronic symptoms and possible recurrence of disease can be detected, known as long-COVID or post-acute COVID [7, 8].…”