Leukemia is a type of bone marrow and blood cancer that affects the blood cells responsible for fighting infections. This can increase a person’s susceptibility to infections and raise uncertainties about COVID-19 vaccinations. However, it is advisable for people with leukemia to vaccinate against COVID-19, as the risks of COVID-19 far outweigh those of vaccines.

Leukemia is an umbrella term for cancers of the blood cells. It usually affects people over the age of 55 years, but it is also the most common cancer among children aged under 15 years.

There are four main types of leukemia, and the National Cancer Institute estimates that more than 61,000 people will receive a diagnosis of leukemia in 2021.

People with leukemia have elevated levels of white blood cells, which are cells that play an essential role in the body’s immune system.

However, these leukemic cells are immature and abnormal, rendering them ineffective for fighting off infections. Due to this, people with leukemia may contract infections more easily and are also more likely to experience potential complications from them.

Because people with leukemia are more likely to experience severe complications from COVID-19, experts recommend that they receive a COVID-19 vaccination and continue to follow preventive measures, such as wearing face masks, following physical distancing guidelines, and washing the hands properly.

This article discusses the safety and efficacy of COVID-19 vaccination for people with leukemia.

A person living with leukemia receiving a COVID-19 vaccination.Share on Pinterest
Pixel_away/Getty Images

Because leukemia affects the immune system, it may cause people to be more susceptible to infections, such as SARS-CoV-2. A 2020 report also notes that people with hematologic malignancies (blood cancers), such as leukemia, are at increased risk of worse outcomes from COVID-19.

Due to this increased risk, the American Society of Clinical Oncology (ASCO) advises people with leukemia to get a COVID-19 vaccine. Additionally, the Centers for Disease Control and Prevention (CDC) encourage people with weakened immune systems, including those with leukemia, to get a COVID-19 vaccine.

Both the ASCO and the CDC say that the only people who should not receive a COVID-19 vaccine are those with a contraindication to it. A contraindication is a condition or circumstance that acts as a reason not to receive a particular medical treatment because of the harm it could cause.

However, people with leukemia may experience a decreased response to the vaccine. Despite this, the vaccine will still likely provide benefits and reduce the risk or severity of COVID-19.

Due to the risk of potential complications from COVID-19, people with leukemia may also be a higher priority for vaccination, allowing them to receive a vaccine as soon as it is feasible.

Also, the CDC now suggests that people receiving therapy to treat cancer, including blood cancers, receive a third vaccine shot.

It is advisable for people to discuss their vaccine options with a doctor. If they are currently receiving immunosuppressive therapy, they may decide to wait a while before getting the vaccine to increase the likelihood of developing immunity from it and to prevent possible complications.

As the medical community furthers its knowledge of the efficacy and safety of COVID-19 vaccinations for people with weakened immune systems, the understanding of the optimal timing and dosing for vaccine schedules will increase.

For example, trials such as the Leukemia & Lymphoma Society’s (LLS) National Patient Registry recently published findings specific to leukemia.

Evidence suggests that COVID-19 vaccines may be less effective in people with cancer, particularly those with blood cancers.

A 2021 study notes that 94% of people with cancer developed seroconversion and antibody responses after receiving two doses of mRNA vaccines but that the hematological malignancy group produced significantly lower levels of antibodies.

However, a 2021 analysis notes that approximately 75% of people with hematologic malignancies still produce antibodies to the SARS-CoV-2 mRNA vaccines.

The same analysis suggests that out of the four main types of leukemia, those with acute myeloid leukemia, acute lymphocytic leukemia, or chronic myeloid leukemia have higher rates of seropositivity after receiving a vaccine than those with chronic lymphocytic leukemia (CLL).

This is consistent with other research noting that people with CLL are less likely to produce SARS-CoV-2 antibodies than healthy people and that responses were particularly low in those actively receiving treatment.

That research also found that people with CLL in remission and those who had not received any treatment responded well to the vaccine compared with patients receiving treatment. Additionally, another 2021 study notes that vaccine efficacy is lower in those receiving CLL-directed therapy.

This emphasizes that antibody responses can vary in people with blood cancer depending on their current treatment and that those who are not undergoing therapy produce more antibodies. This implies that timing for vaccination is an important consideration and something that people should consider discussing with a doctor.

A recent survey by the LLS National Patient Registry suggests that COVID-19 vaccine safety and tolerability are similar between those living with blood cancer, blood cancer survivors, and the general public.

Although there are limited data, current evidence from the CDC also indicates that it is both safe and advisable for people with underlying medical conditions, including those with weakened immune systems, to receive the COVID-19 vaccine.

Experts consider people with cancer as part of the higher priority group and recommend that these people get vaccinated as soon as possible. Although the immune responses of people with blood cancers may not be as strong, vaccines can still offer some protection against COVID-19.

However, people should first discuss their options with a doctor, as there are variables to consider, such as their current condition and treatment regimen.

Individuals in the United States can visit vaccines.gov to look for vaccine locations near them, or they can check their state health department.

Both people who have received the vaccine and those waiting to get vaccinated should continue to take preventive measures, including maintaining physical distancing, doing proper hand washing, avoiding crowded and poorly ventilated places, and wearing face masks.

This also emphasizes the importance of family members, friends, and members of a person’s healthcare team also receiving their vaccinations and continuing preventive practices.

It is important for people to follow a doctor’s advice on treatment options and to report any unusual symptoms. A 2021 review suggests that it may be advisable to use less intensive therapies, reduce patient visits, and establish collaborative care at local centers or use telemedicine to reduce potential exposure while maintaining optimal and effective treatment.

People with leukemia and other blood cancer may be more susceptible to SARS-CoV-2 infections and severe complications of COVID-19. For this reason, it is advisable that people with leukemia get their COVID-19 vaccination as soon as it is feasible for them to do so. They should discuss their options, and any concerns they have, with a doctor.

Although evidence seems to highlight that the vaccine may not produce as strong a response as it may in other people, it is still effective and can provide a level of protection that can help reduce the risk of severe complications from COVID-19.

Research also notes that the vaccine is safe for people with leukemia, indicating that the risks of COVID-19 far outweigh those associated with vaccines.