Discussions about COVID-19 and vaccines often mention immunocompromised individuals’ risk for serious infection and whether those individuals will need vaccine boosters. But what does it mean to be immunocompromised? Last month’s blog post explored the basics of immunity, so you might want to check that out if you need a reminder of B-cells, antibodies, macrophages, and T-cells. This month, let’s look at the basics of what it means to be immunocompromised.
When you’re immunocompromised, your immune system isn’t functioning properly. That means you can get sick more quickly and more severely than people with fully functional immune systems. According to Dr. David Porter, there are five major things that can weaken your immune system:
- Chronic diseases that destroy immune cells such as HIV and autoimmune diseases (diseases that cause the body’s immune system to attack itself) such as lupus can impact your immune system.
- Medical treatments such as chemotherapy which destroys healthy cells as it destroys cancer cells as well as immunosuppressive treatments used for autoimmune diseases can leave your immune system weakened.
- Organ and bone marrow transplants can also impact your immune system because, during these transplants, you may be lacking white blood cells or you may need to take anti-rejection medications that suppress your immune system so your body doesn’t fight the new organ.
- Age can be a factor because, as you get older, your immune system doesn’t function as well.
- Smoking could possibly impact your immune system. Studies show smokers tend to get sicker than non-smokers (as cited in Penn Medicine, 2020).
Dallas (2015) adds stress, grief, diet, and alcohol can negatively impact your immune system because these factors alter hormonal and chemical balances in your body which regulate the immune system. A sedentary lifestyle can also weaken your immune system because it predisposes you to chronic health problems.
You can be temporarily or permanently immunocompromised depending on what is causing your weakened immune system. People who are permanently immunocompromised must take extra precautions to stay safe even when the world is not experiencing a pandemic, and some of these precautions include regularly wearing masks during flu seasons, avoiding crowds, and maintaining physical distance when possible. For people who are immunocompromised due to chronic and autoimmune diseases, these precautions can be critical for survival in addition to managing the disease.
Immunocompromised individuals may be unable to receive routine and recommended vaccinations if those vaccinations contain live virus, which makes it all the more important for people who can get routine and recommended vaccinations to get them in order to achieve herd immunity so immunocompromised people are protected.
Between two and four percent of U.S. adults are immunocompromised (Sun, Abutaleb, & McGinley, 2021). Many autoimmune diseases go undiagnosed for years. There is an aging and increasingly medicated population in the U.S., thus the number of immunocompromised patients is likely to grow.
Lymphocytes are white blood cells in the immune system. B-cells and T-cells, which I discussed in last month’s blog post, are lymphocytes. B-cells produce antibodies. T-cells regulate the immune system and attack antigens if they get past antibodies. Martel (2020) tells readers that B-cells fight off bacterial infections while T-cells fight off viral infections. When either of these lymphocytes is deficient, you’re immunocompromised.
B-cell deficiencies and autoimmune diseases
B-cells produce antibodies to protect us from diseases, however Mallick (2020) explains sometimes B-cells produce antibodies to antigens that are our own cells. That can be a component of autoimmune diseases. Some common autoimmune diseases are type 1 diabetes, multiple sclerosis, psoriatic arthritis, and irritable bowel syndrome. Watson (2019) provides an overview of other common autoimmune diseases. A primary method of treating autoimmune diseases is with medication that calms overactive immune systems. These medications are known as immunosuppressants and, as their name implies, they suppress or weaken the immune system. Giorgi (2019) explains more about immunosuppressants.
One method of treating multiple sclerosis and other autoimmune diseases is B-cell therapy, otherwise known as B-cell depletion. This therapy, which was originally used to treat cancer-causing B-cells, uses monoclonal antibodies to attack the B-cells. Depleting the B-cells in your body may help an overactive immune system from attacking itself, but it leaves you vulnerable to bacterial infections, and it negatively impacts your T-cells because you can’t adequately respond to infections and produce antibodies. Rath (2020) provides an overview of B-cell therapy and its use in multiple sclerosis. Lee, Rojas, and Gommerman (2021) talk about B-cell therapy and other autoimmune diseases.
B-cell deficiencies can also be caused by genetics and other problems with various parts of the immune system. The National Library of Medicine’s MedlinePlus (2021) page on immunodeficiency disorders provides additional information.
T-cells do not produce antibodies, so T-cell deficiencies will not cause the body to attack itself; however, T-cell deficiencies leave you vulnerable to viral infections.
As noted above, T-cell deficiencies can be a side effect of treatments that deplete your B-cells.
T-cells are also impacted by chronic diseases. According to Ludwig-Maximilians-Universität München (2021) in a press release to ScienceDaily, T-cells can lose their functionality and become “exhausted” when they’re fighting their target antigens for too long. Chronic diseases may impact T-cells in other ways; for example, HIV kills certain T-cells because the virus hijacks the T-cells to make copies of itself. Studies have shown cancer treatments also have lingering negative effects on T-cells, and the American Cancer Society (2021) explains that even when utilizing chimeric antigen receptor (CAR) T-cell therapy, you can have a weakened immune system. Finally, you can inherit disorders that negatively impact your T-cells (U.S. National Library of Medicine, 2021).
Cancer and Immune Deficiency
It’s already been noted that cancer treatments such as chemotherapy and CAR T-cell therapy can weaken your immune system. Cancer Treatment Centers of America (CTCA, 2021) explain chemotherapy and radiation damage the immune system because as these treatments kill cancer cells, they kill healthy cells; chemotherapy can also damage bone marrow that produces immune system cells. CTCA adds that immunotherapy treatments, which boost the immune system, can boost it too much and lead to healthy cells being attacked.
Major surgery for cancer treatment can negatively impact the immune system because of side effects of anesthesia drugs and because surgery breaks the skin and mucous membrane barriers that help protect us against infections. In fact, according to the American Cancer Society (2021), it can take many months for your immune system to fully recover from surgery.
But in addition to cancer treatment impacting the immune system, the American Cancer Society (2021) tells us that cancers such as lymphomas, multiple myelomas, and leukemia can actually change the way the immune system blood cells work, thus weakening the immune system.
Immunocompromised Patients and COVID Vaccines
Immunocompromised patients have been able to receive the COVID-19 vaccines because they do not contain live, attenuated virus. The CDC and FDA are currently investigating whether to recommend a booster COVID-19 vaccine for immunocompromised individuals. Haslett (2021) tells readers a CDC advisory panel recently offered support for immunocompromised patients receiving a booster, but didn’t offer a formal recommendation. Update: On August 12, 2021, the FDA authorized a COVID-19 booster for some immunocompromised individuals. Read more in the FDA’s press release.
Solis-Moerira (2021) points to studies that show immunocompromised patients do not have as great an antibody response to vaccines as patients who are not immunocompromised; these differences in responses are not uniform across all immunocompromised patients. This is troubling and is of particular concern as mask mandates are increasingly being dropped because immunocompromised patients are at a higher risk for suffering severe complications from COVID.
Serious But Not Always Visible
Clearly immunocompromised patients can face serious health challenges. A weakened immune system means much more than easily catching a cold. Unless someone is exhibiting outward side effects of diseases that are impacting their immune system, you may not realize that person is immunocompromised. Whether we’re in a respiratory virus pandemic or a normal cold and flu season, it’s important to understand the delicate balance of our immune system and take basic public health precautions such as handwashing, covering your mouth when you cough, staying home when you’re sick, and getting routine and recommended vaccinations to protect ourselves and each other.