COVID-19 and People with Sickle Cell Disease (SCD)
Risk of infection in Sickle Cell Disease and benefits of preventative measures
- People with SCD have always had an increased risk of complications of infections of both viral and bacterial infections. The COVID-19 vaccine has been given to millions of people and has decreased infections, hospitalizations, and, most importantly, death. People with SCD need to know the facts about vaccines, their benefits and side effects to make an important decision.
- In the United States (US), decades ago, people with SCD did not live past childhood because of death from infections. The implementation of all babies with SCD taking prophylactic penicillin and vaccines against viruses and bacteria dramatically changed the survival rates. The routine use of preventative vaccines is a primary reason 95% of children with SCD survive into adulthood. These measures have been administered safely to almost all newborns with SCD in the US. In countries with limited resources and the inability to provide preventative measures, childhood death from infection is unfortunately commonplace, and most patients do not survive into adulthood.
- In adults, acute chest syndrome (ACS) or pneumonia is a leading cause of death and morbidity in all patients with SCD throughout life. A viral infection can trigger severe pneumonia in SCD patients, activating sickling in the lungs and a painful event. You may remember the influenza virus H1N1, which caused a public health crisis in 2009. People with SCD who were infected by the influenza virus had a much higher hospitalization rate and severe illness. However, people with SCD who received the flu vaccine had fewer complications from influenza infections. However, flu vaccines were extremely helpful in minimizing the risk of H1N1 complications for people with SCD. COVID-19 is a viral infection similar to H1N1 but more contagious and severe for people with SCD than the general population.
COVID-19 has increased the annual death rate and decreased the survival rate in the sickle cell population
- A detailed analysis of the annual total death rates in SCD since 2014 was completed by Dr. Amanda Payne with the Centers for Disease Control (CDC) to understand the impact of COVID-19 on SCD. The total deaths per year of people with SCD remained stable in 2020. However, under the COVID-19 epidemic, the total deaths have increased by 12% per year because of COVID-19. Overall, the case fatality rate was 7% in the total cases analyzed, with the average age of the population being 29 years of age. Because of COVID-19, the overall lifespan of people with SCD has decreased. In SCD, death and serious hospitalization were age-related.
- Therefore, the average overall survival age in people with SCD has slowly decreased. In SCD, patients over 60 years of age accounted for 32% of all deaths. But excess deaths were also noted in younger age groups.
Non-fatal effects of COVID-19 in SCD
- Most patients with SCD do not die from COVID-19. Many do not require hospitalization and experience an uncomfortable flu-like illness, including cough, joint pain, headaches, diarrhea, loss of taste, and congestion. In the younger population, many patients may show no signs of symptoms. But they can spread the serious infection to older patients.
- In SCD, COVID-19 often triggers a severe painful event without the classic findings signs of a COVID-19 infection.
- In the general population, COVID-19 causes a higher rate of thrombosis or blood clots in the body and the lungs. People with SCD already have an increased risk of clots which a COVID-19 infection can trigger.
- The most common serious complication in the general population for COVID-19 is pneumonia, including a severe form of ARDS (acute respiratory distress syndrome). In the general population, the oxygen level in the blood can drop to dangerous levels before the patient develops difficulty breathing. Therefore, many people monitor their oxygen level with an over-the-counter pulse oximetry device. This small device is clipped to the tip of the finger and reports the oxygen level. In people with SCD, a drop in oxygen level is much more dangerous than in people without SCD. When the oxygen level drops, it causes the red cells to sickle throughout the body, especially in the lungs, and can clog the blood flow in other important organs such as the brain.
- In hospitalized patients with COVID-19, neurologic symptoms are common, including headache, confusion, and occasionally seizures, and some may even experience a stroke. People with SCD have a high risk of stroke before COVID-19 and may be more susceptible to these complications.
- Patients who have recovered from COVID-19 are at risk for persistent symptoms that may last for months, including chronic fatigue, memory impairment, shortness of breath, and psychological problems. These risks in SCD patients have not been well studied but are a concern.
- Children with COVID-19 are less symptomatic and account for 19% of new COVID-19 cases in the US. The percentage of children becoming COVID-19 positive is dramatically increasing. All children are at risk of getting COVID-19, but the hospitalization rate for children is very low. Death in children without SCD is rare, but the complication rate is affected by health disparities, increasing the likelihood of seriousness by 2-3-fold in underrepresented populations. Children with SCD also have a mild infection, but experience increased hospitalizations, pain events, uncommonly life-threatening pneumonia, and neurologic side effects. Children generally have a small risk of a multi-system inflammatory syndrome complication. This complication can lead to rare, devastating complications characterized by severe inflammation in the body. The exact risk in children with SCD is unknown.
COVID-19 vaccine in general and in SCD
COVID vaccine
- When viral and bacterial infections enter the body, they multiply and attack the patient's organs, making them sick. The immune system in the body responds by making proteins that kill the infection. Vaccines stimulate the body as if it has an infection to make infection-killing proteins. There are different types of vaccines. The COVID-19 vaccine, particularly the types we use (mRNA), is not a live infection and cannot cause COVID-19. They include a small piece of the virus's genetic material that activates the immune system. This material does not affect the person's own DNA. Getting the vaccine lowers the likelihood of disease, hospitalization, and death as long as the antibodies stimulated by the vaccine remain adequate.
- Many studies found dramatic differences in infections in immunized patients vs. non-immunized patients. For example, in one of the first studies using the mRNA vaccine, 30,000 people volunteered. They were immunized with the vaccine or a placebo vaccine (an injection that does not have active vaccine components to affect health). They were followed closely and evaluated for infection prevention and side effects. As a result, the vaccine was 93% effective in preventing COVID-19 (Graph A) and 98% (Graph B) effective in preventing severe COVID-19.
COVID vaccine in SCD
- People with SCD and other chronic illnesses may have a lessened response to the COVID-19 vaccine, which is why two shots and a booster are recommended. Limited data on the response to the vaccine is available in SCD patients. In a recent study, following people with SCD that received their first dose of the COVID-19 vaccine, 44% obtained an adequate level of antibodies to protect from infections. After the second dose, all patients reached sufficient levels of infection-fighting antibodies. However, how long the antibodies remain at a safe level was not determined.
Side effects of the COVID-19 vaccine
- Millions of people and thousands of SCD patients have gotten the COVID-19 vaccine, and had no major side effects. The Vaccine is FDA approved for all individuals from infancy through adulthood. In addition, the vaccine is safe in pregnancy and recommended in patients who have recently become pregnant.
- The vaccine does not increase the risk of sickle cell complications or pain events.
- Sickle cell patients have similar side effects as the general population and do not have an increased frequency of pain.
- The vaccine can cause mild side effects for up to two days. These side effects generally do not interfere with one's functioning. Up to 60% of immunized people experience mild side effects for the first two days, with 50% of people having some reaction. The other 50% do not experience any symptoms. These common side effects include 1) pain, redness, and itching at the site of injection, 2) fatigue, mild headache in 20% of people, and 3) low-grade fever and joint aches. Serious reactions are very rare. Anaphylaxis or severe allergic reaction has occurred in 2 or 3 cases per million doses. Over 90% of those cases occur right after the vaccine, during the brief 15-minute period where you are required to be under observation.
Since COVID-19 is a serious, at times life-threatening infection in SCD, sickle cell centers, including ours, are working together to develop the best prevention methods, improve treatments and evaluate any long-term side effects. In chronic diseases, the vaccine may have a shorter duration of protection than the general population. Knowing this information would enable the most effective schedule recommended. Sickle cell centers are studying the vaccine duration of protection and other therapies. If you are interested and would like to know more about this study or other therapeutic trials to improve sickle cell outcomes available to you, please let a member of the sickle cell team know.
Video resources
Informational video resources that from patients and experts.
SCDAA COVID-19 information and resources
Several discussions and videos among experts and patients.
Sickle Cell Disease Association of America, Inc.
Sickle Cell disease and COVID-19
An interview with Wanda Whitten-Shurney, a primary care provider, leading pediatrician, and advocate for sickle cell disease.
Getting the COVID-19 vaccine: Sickle Cell patient stories
Sickle patients in England discussing the vaccine.