The attitude towards possible Covid infection has relaxed considerably over the past year. People seem willing to accept a Covid encounter if the risk to life is small. Most people don’t seem to be aware of the fact that Covid differs from the flu in that while the respiratory system is the normal point of access for both, the flu remains active there while the Covid virus can migrate to the rest of the body’s organs and do damage. The brain and cardiovascular system appear to be of particular interest to the virus. A significant number of infected people will have long-term health issues after the initial infection has dissipated. This effect has earned the designation “long Covid.” The level of long Covid incidence seems to depend on who is surveying the population and what is the threshold for concern. The state of knowledge of long Covid as of a year ago was discussed in The Covid Pandemic Has Been Terrible, but We Do Not Yet Know How Terrible. The concern at the time was that the costs and resources needed to treat an ever-growing number of long Covid sufferers could produce a medical catastrophe. That concern has not gone away.
Jason Gale provided an interesting assessment of the current state of knowledge in an article for Bloomberg Businessweek: Long Covid’s Effects Go Beyond Respiratory Issues. That is the online title, the one in the paper edition had the more intriguing title Covid Cluster Bomb. Gale begins with this lede.
“The coronavirus can attack multiple organs and weaken overall immunity for months. Its impacts are evident in global death rates that remain high.”
“Virus-damaged organs and compromised immune systems are just part of Covid’s public-health legacy; there’s also a litany of secondary effects still being measured, ranging from increases in mental illness to delays in getting cancer treatment. Some doctors also blame Covid for worsening the effects of other diseases, as with the cases of flu and respiratory syncytial virus [RSV] now mobbing children’s hospitals.”
The greatest concern is that a Covid infection can produce long-term morbidities (illnesses) that can lead to early death long after the initial encounter.
“Unlike influenza, which attacks the lining of the airways, SARS-CoV-2 resembles a multisystem cluster bomb. ‘That’s a total game changer, because it’s not just your lungs,’ says Sonia Sharma, an associate professor at the Center for Autoimmunity and Inflammation at the La Jolla Institute for Immunology, near San Diego. ‘You’ve got a battle going on between the virus and your immune system, and that battle can happen in almost any organ’.”
“In the most insidious cases, Covid silently inflames and damages tissues or causes clotting abnormalities before manifesting as cardiovascular disease, diabetes, kidney impairment or brain damage. Multiple studies show former Covid patients who had disease at all levels of severity have an increased risk of dying or being hospitalized for complications 6 to 12 months later. An estimated 7.7 million to 23 million Americans are affected by long Covid, the Department of Health and Human Services said in a report in November.”
Detailed studies of effects on specific organs are beginning to become available. Consider the affects of infection on kidneys.
“In the year after a Covid infection, patients experienced a decline in kidney function equivalent to that from four years of normal aging, according to research by epidemiologist Ziyad Al-Aly, director of the Clinical Epidemiology Center at the Veterans Affairs St. Louis Health Care System in Missouri. Even nonhospitalized Covid patients with no preexisting renal problems have almost a twofold higher risk of developing end-stage kidney disease, compared with someone who’s never had Covid.”
Similar effects seem to be occurring in other organs leading to life-threatening illnesses.
“Compared with noninfected counterparts, survivors have about a 63% increased risk of an array of potentially deadly cardiovascular problems, including abnormal heartbeat, inflammation, clots, strokes, heart attacks and heart failure in the year after recovering from the illness’s acute phase, according to a study by Al-Aly and colleagues, published in February. ‘Once the inflammatory process rages through, it’s like a war zone in some patients,’ says Andreas Bart, medical director of the Center for Inherited Heart Diseases at Johns Hopkins University in Baltimore. ‘They might not have died immediately from Covid but from the complications of acute Covid disease’.”
A Lancet article, Long-term mortality followingSARS-CoV-2 infection: A national cohort study from Estonia, supports these results and indicates even incidences of cancer are more frequent after a Covid infection, and that older people with age-weakened immune systems are the most vulnerable.
“Importantly, as per our results, increased mortality among those infected with SARS-CoV-2 extends beyond early (acute COVID) period. We observed an excess of cardiovascular, cancer, respiratory and other diseases related mortality extending over a year among the older SARS-CoV-2 cases. We believe this to be a significant finding. After the acute disease period, the older SARS-CoV-2 cases were at increased risk for respiratory diseases, malignant neoplasms, and cardiovascular deaths.”
With present attitudes toward Covid, it is likely that eventually everyone will be infected, many people several times. This from Gale.
“While vaccination has been shown to attenuate the disease initially caused by SARS-CoV-2, repeated infections appear to compound the risk of harm, a study published in November in the journal Nature Medicine showed. Three in five Americans had been infected with the coronavirus at least once as of February, up from 33% a year ago. ‘You’re talking really large numbers and lots of people who were exposed, but may not even know they were affected,’ says Harlan Krumholz, director of Yale University’s Center for Outcomes Research and Evaluation. A proportion of patients may develop complications much later. ‘That’s going to also take a major toll—maybe a bigger toll than even the pandemic itself,’ he says.”
Old people, let the young do dumb things on the assumption
that they will live forever, but for us some appropriate masking and social
distancing is still a good idea.
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