How We Survive COVID-19 Infection.
COVID-19 is currently the most discussed concern for most of us. We all know the “guidelines” that include personal hygiene and social distancing with mitigation to prevent the spread. Prevention of getting infected is our best chance of staying healthy. Currently there is no confirmed treatment regimen. How then do most people survive if they become infected with this virus? The management of an infected patient can become medically complex and very challenging with the goal largely focused on “buying time” to keep the patient alive long enough for the immune system to conquer the invading virus. Why do many recover with minor or no symptoms while others become critically ill or die? Remember the virus causing COVID-19 is a genetically novel micro-organism that humans have never faced in our past history.
Humans live in an environment teeming with micro-organisms and could not exist as a species without highly effective mechanisms of host defense. The innate immune system constitutes the first-line barrier, the rapid-response mechanism, to prevent microbial invasion. Its components are inherited from parent to child and directed against molecules expressed only by micro-organisms. The immune system and its response in humans is a very complex, interactive and dynamic system that can vary dramatically between different individuals.
“Innate” immunity refers to immune responses that are present from birth and not learned, adapted, or permanently heightened as a result of exposure to micro-organisms, in contrast to the responses of T and B lymphocytes in the adaptive immune system. The importance of innate immunity can be appreciated by considering that the generation time of most micro-organisms is 20 to 30 minutes, whereas the development of a specific adaptive immune response with antibody and T cells takes days to weeks. The innate immune system protects the host during the time between microbe exposure and initial adaptive responses. Managing patients with micro-organism infections that have not had prior exposure and no vaccination, requires time for the adaptive immune response to develop. (Remember, no one living has ever had prior exposure to SARS-CoV-2). When the viral load overwhelms the innate immunity response, recovery becomes increasingly dependent on the adaptive immune response that takes time to develop. The overall health of the immune system is vital to an effective response.
The pervasive distribution of host defense immune capacity and its attendant inflammation, essential to survival, can also contribute to the pathogenesis of organ-specific diseases and acute organ failure. Numerous disease states adversely affect our immunity and have also developed related to impaired immunity, including type 2 Diabetes, cardiovascular disease, hypertension, kidney and chronic lung impairments, obesity and even cancers. Innate immunity often wanes in the elderly.
In COVID-19 some patients experience Cytokine release syndrome (CRS), an acute systemic inflammatory syndrome characterized by fever and multiple organ dysfunction or failure including severe interstitial pneumonia with potentially unsustainable hypoxemia. Ventilatory support may be required to “buy time” for the adaptive immune system to conquer the virus and allow the intense inflammatory response to subside. In those individuals with an impaired immune system, extra time provided by medical support may prove inadequate, resulting in death.
In addition to providing a first line of defense against microbes, the innate immune system activates and instructs adaptive immune responses, regulates inflammation, and mediates immune homeostasis (the balance between opposing pro-inflammatory and anti-inflammatory processes).
Essential functions of the innate immune system include the following:
●Detection of micro-organisms and first-line defense against invasion and infection.
●Regulation of inflammation – The cardinal signs of inflammation [swelling, redness, heat, and pain]) are products of the protective action of innate immunity. To limit damage to the host, these responses must also be terminated when no longer needed.
●Maintenance of “immunologic homeostasis” within the host.
●Activation and instruction of adaptive immune responses.
Perhaps an important lesson to be learned during our COVID-19 crisis is that an intact, healthy immune system is vital and can be life saving. Each of us is gifted with an immune system at birth. The component under our control is governed by our life style. Our choices related to this are key to promoting and maintaining a strong immune system. The important components of lifestyle that promote health include consistent ingestion of wholesome nutrition, regular graded and strategic exercise, adequate sleep and a healthy mind-set. The Elite Fitness Plus Family has been well informed regarding this life style and those of us that consistently employ this approach should generally do well in surviving this crisis.
Paul R. Block, MD, FACP, FCCP
Be Sociable, Share!