Physiology Online recently published a review (09/11/23) exploring long Covid and its impact around the human body. The review discusses long COVID, which refers to ongoing COVID-19 health effects lasting months after initial infection. Symptoms can include fatigue, brain fog, cardiovascular issues, and others affecting multiple organ systems. The underlying mechanisms likely involve chronic inflammation, autoimmunity, and microclots. Understanding the immunological mechanisms is key to developing treatments.
Risk factors for long COVID include severe initial illness, older age, and pre-existing conditions. Theories on causation include viral persistence, immune dysregulation, autoimmunity, endothelial damage, and hypercoagulability. Symptoms can persist for 6-12 months or more and affect the lungs, brain, heart, gastrointestinal system, endocrine system, and others.
COVID-19 impacts the immune system long-term, triggering cytokines like IL-6 and IFN-γ. Viral reservoirs may persist for months. Autoantibodies and autoreactive T-cells may cause ongoing inflammation and damage. Children may develop multisystem inflammatory syndrome weeks after infection.
Long COVID poses a significant global health burden, affecting an estimated 65 million people. Symptoms like fatigue, shortness of breath and “brain fog” are most common. Up to 80% of hospitalized patients have ongoing cognitive or physical symptoms after 2 years. Long COVID increases healthcare usage and reduces quality of life.
Management involves medications to treat symptoms, rehabilitation, and psychological support. Vaccines may reduce long COVID risk by aiding virus clearance and reducing inflammation. Research priorities include identifying mechanisms, risk factors and tailored treatments.
In conclusion, long COVID involves heterogeneous, multisystem effects that can persist for months or years after infection. Understanding the immunological mechanisms can aid diagnosis, treatment and management of this growing public health crisis.
Read the full article here.