Thousands of scientific research papers on Covid-19 and SARS-CoV-2 are being published each week and with them comes a clearer picture of the virus and the disease it causes. There’s still a lot we don’t know, but the article published by Science magazine is the best synthesis of the emerging science that I have read.
It details that the disease can attack almost anything in the body with devastating consequences and clinicians are realizing that although the lungs are ground zero, its reach can extend to many organs including the heart and blood vessels, kidneys, gut, and brain.
As per article this is how infection begin:
The virus requires receptor angiotensin-converting enzyme 2 (ACE2) to enter a cell. ACE2 present throughout the body, which normally helps regulate blood pressure. Symptoms may be absent when virus is making myriad copies of itself and invading new cells or one may develop a fever, dry cough, sore throat, loss of smell and taste, or head and body aches. If the immune system doesn’t beat back SARS-CoV-2 during this initial phase, the virus then marches down the windpipe to attack the lungs.
Lungs airsacs, called alveoli, lined by a single layer of cells that are rich in ACE2 receptors. If virus enters alveoli, Inflammatory molecules called chemokines will be released by WBC which summon more immune cells that target and kill virus-infected cells, leaving a stew of fluid and dead cells, puss behind. Immune cells crowd an inflamed alveolus, whose walls break down during attack by the virus, diminishing oxygen uptake as Oxygen transfer through these alveoli . Patients cough, fevers rise, and it takes more and more effort to breathe.
Though Covid-19 attack begins in the lungs, it is as much a vascular disease as it is a respiratory disease and evidences to support this was mentioned in article.
This article gave an interesting update that, Mangalmurti, a pulmonary intensivist at the Hospital of the University of Pennsylvania (HUP) says she has been “shocked by the fact that we don’t have a huge number of asthmatics” or patients with other respiratory diseases in HUP’s ICU. “It’s very striking to us that risk factors seem to be vascular: diabetes, obesity, age, hypertension.”
The worldwide fears of ventilator shortages for failing lungs have received plenty of attention. Not so a scramble for another type of equipment: dialysis machines. “If these folks are not dying of lung failure, they’re dying of renal failure,” says neurologist Jennifer Frontera of New York University’s Langone Medical Center, which has treated thousands of COVID-19 patients. The need for dialysis may be because the kidneys, abundantly endowed with ACE2 receptors, present another viral target.
As per the article this is how virus or the body’s response to it, injuring many other organs.
This map of the devastation that COVID-19 can inflict on the body is still just a sketch. It will take years of painstaking research to sharpen the picture of its reach, and the cascade of cardiovascular and immune effects it might set in motion.
Reference: Science magazine
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