Telomere shortening is one of the reasons our immune systems weaken over time. The COVID-19 coronavirus, like the flu, is especially dangerous to the elderly. As well as being a major risk factor for developing a variety of non-infectious health issues like diabetes and dementia, telomere shortening also puts us at risk for a variety of viral and bacterial infections (Effros, 2011).
Telomere shortening happens to everyone, but how quickly depends on the person. People in their nineties and beyond live that long partially because their immune systems remain largely intact. In fact, studies have repeatedly found that those over ninety maintain relatively long telomeres (Terry, Nolan, Andersen, Perls, & Cawthon, 2008). Telomere shortening results in cellular senescence. Senescent cells no longer divide and contribute to inflammation.
In a paper titled "Telomerase induction in T cells: a cure for aging and disease? Rita Effros notes that during an infection CD8 T cells, which defend the body from microbial invaders, can reach their Hayflick limit by depleting their telomeres. If your telomeres are already short, then this is more likely to happen.
Naive T and B cells are particularly important when our bodies encounter new pathogens like the like COVID-19 coronavirus. Naive T and B cells are still inexperienced and ready to learn. The adaptability of our immune system depends on the quantity of these cells (Hodes, 2002).
Aging results in a decline of naive T and B cells as well as a total loss of T and B. Telomere shortening does not obliterate immune response. The most ancient part of our immune system, which fights invaders through inflammation, remains intact well into old age. But the adaptable parts dwindle - making it harder for us to fight off infections, especially ones we've never encountered.
Nobel laureate Elizabeth Blackburn goes into detail about the relationship between stress and telomere shortening with Elissa Epel.
The relationship between stress and the development of cold sores brought on by the herpes simplex virus is well-documented. Many people have witnessed or inexperienced this firsthand. A 16 week study on elderly people who received the Varicella-Zoster vaccine (VZ is responsible for chickenpox) showed that 16 weeks of tai chi was linked with greater cellular immunity (Irwin et. al, 2016). As interesting as these findings may be and as vital as stress management is to nearly every aspect of our health, it’s not enough to fight a pandemic.
The chronic conditions of aging are an international health concern. While even advanced regenerative medicine will not eliminate the need for vaccines, quarantines, and other measures to contain potential pandemics, it will reduce the costs to governments and the number of lives they take.
Although the millions suffering from age-related diseases are largely ignored by the general public, dismissed as collateral damage of "natural" processes, perhaps the coronavirus will serve as a reminder that aging is the root cause of disease.
References and Suggested Reading
Hodes, Richard J., Karen S. Hathcock, and Nan-ping Weng. "Telomeres in T and B cells." Nature reviews immunology 2.9 (2002): 699-706.
Kaszubowska, L. "Telomere shortening and ageing of the immune system." J Physiol Pharmacol 59.Suppl 9 (2008): 169-186.
Effros, Rita B. "Telomere/telomerase dynamics within the human immune system: effect of chronic infection and stress." Experimental gerontology 46.2-3 (2011): 135-140.
Effros, Rita B. "Telomerase induction in T cells: a cure for aging and disease?." Experimental gerontology 42.5 (2007): 416-420.
Irwin MR, Olmstead R, Oxman MN. Augmenting immune responses to varicella zoster virus in older adults: a randomized, controlled trial of Tai Chi. J.Am.Geriatr.Soc. 2007;55:511–517.
Terry, Dellara F., et al. "Association of longer telomeres with better health in centenarians." The Journals of Gerontology Series A: Biological Sciences and Medical Sciences 63.8 (2008): 809-812.
Weng, Nan-ping. "Aging of the immune system: how much can the adaptive immune system adapt?." Immunity 24.5 (2006): 495-499.