For about three months now, the world has been struggling to respond to the rapid spread of the novel coronavirus, also known as COVID-19, now designated a pandemic by the World Health Organization. As has been reported widely in the media, the elderly appear to be more vulnerable to the virus than younger people, and elderly men are the most vulnerable. Although, the latest statics differ from this observation. Imperial College London, published a study on March 30, noted that among people who were infected with the virus, those in their 70s and 80s had higher mortality rate, and also, they are more likely to require hospitalization.
Researchers have been busy trying to figure out what exactly it is that makes the elderly more vulnerable to COVID-19, with fatal results. This will help governments and medical professionals to reduce the number of deaths among the elderly before the virus is brought under control. Researchers have found that COVID-19 patients, both elderly and young, are more likely to succumb to COVID-19 if they have “pre-existing conditions”—that is, one or more chronic illnesses that the person had before being infected with COVID-19. Thus, age is not the most important factor in determining who gets ill from the virus. For example, a healthy 80-year-old may be more successful at fighting off the infection than a 60-year-old who has diabetes or heart disease.
The main reason that a person of any age is more likely to have difficulty fighting off the virus is compromised immune system. We know that the human immune system begins to weaken very early on and experiences the onset of a sharp decline by about age 40. The immune system has two lines of defense in dealing with any infection. The first is a general rapid-response mounted by cells known as leukocytes, which go into action within minutes or hours after the virus (or other infectious agent) enters the body. Several days later, the second line of defense takes over in the form of antibodies and T cells, which target the specific type of virus (or infectious agent).
The problem is that this second line of defense weakens more rapidly than the first. By puberty, the body is producing ten times fewer T cells than it did at birth, and by about age 40, there is another tenfold drop in the production of T cells. T cells have a “memory” in the sense that they can recognize a virus that they have encountered before and can get rid of it more efficiently. With a new virus, such as COVID-19, the T cells need to figure out how to get rid of it, but older people have fewer T cells to do this job. Also, as we get older, the B cells, which produce antibodies, become less efficient at producing antibodies to fight the infection. Another problem is, the communication between the two lines of defense slows down, so the second line of defense is slower to take over the job of fighting the infection. This means that the leukocytes from the first line of defense keep doing their job longer than they normally would, with the result that the body becomes flooded with inflammatory substances known as cytokines, produced by the leukocytes. An excess of cytokines in the body causes severe breathing problems, which is one of the major causes of death among those infected with COVID-19. A study by the Jackson Laboratory for Genomic Medicine, published in February, found that older men have a more robust first line of defense, with more cytokine-producing cells, while older women have more numerous and more efficient B cells and T cells. This may explain why older men have been more adversely affected than older women by COVID-19.
In this time of crisis our elderly loved ones must follow and should be assisted to follow all the guidelines and precautions issued by the local, state and federal health authorities.
Veena J. Alfred, PhD., Certified Dementia Practitioner