How Immunizations Play a Role in the Treatment of Sickle Cell Disease

People with sickle cell disease are immunocompromised, which means they have an increased risk of infection. For this reason, immunizations are an important part of complete sickle cell care.

This article looks at the importance of immunizations for people with sickle cell disease.

Why People With Sickle Cell Disease Are at Risk for Infections

Sickle cell disease starts damaging the organs in the first year of life. One of the first organs affected is the spleen. The spleen is a small organ on the left side of the abdomen underneath the ribcage. The spleen filters the blood and removes old, damaged red blood cells.

The spleen is also an important part of the immune system. It has two immune functions. It filters out bacteria, particularly a type of bacteria that has an outer covering that helps protect it from the body's immune system. It also produces lymphocytes, white blood cells that help make antibodies to infections or in response to immunizations.

People with sickle cell disease have sickle-shaped blood cells. These cells can stick together and pool in the spleen, which damages it. The damage occurs repeatedly and spleen function is lost before the age of 5. This loss of function significantly increases the risk of infection.

Potentially Harmful Bacteria

People with sickle cell disease are at higher risk of developing serious bacterial illnesses. For example, people with sickle cell disease are roughly 300 times more likely to develop bacterial meningitis than people without the condition. Bacterial meningitis is a serious infection of the lining of the brain. 

Sickle cell disease also raises the risk of bacteremia, a bacterial infection of the blood. Without antibiotics, unvaccinated children with sickle cell disease who develop a fever have a 3% to 5% risk of developing bacteremia. 

Additionally, people with sickle cell are more likely to develop sepsis, a blood infection that causes a major inflammatory reaction.

Bacteria that can cause these infections include:

• Streptococcus pneumoniae: These bacteria are a common cause of pneumonia in children and adults. They can also cause meningitis, bacteremia, and sepsis.
• Neisseria meningitidis: This species is the number one cause of bacterial meningitis in children and young adults. It can also cause bacteremia or sepsis.
• Haemophilus influenzae type b: Prior to routine vaccination, this used to be the leading cause of meningitis in children. It should not be confused with the influenza virus.

In addition, influenza is a virus that causes respiratory infections. People with sickle cell disease who develop an infection with influenza are more likely to be admitted to the hospital. Influenza infection can also trigger lung complications like acute chest syndrome.

Recommended Immunizations

Immunization can help protect people with sickle cell from developing serious infections. Children with sickle cell should receive all recommended childhood vaccines as well as an annual flu shot. Adults should make sure their vaccinations are up to date. Special vaccine schedules are recommended for certain vaccines, including:

• Haemophilus influenzae type b (Hib)
• Pneumococcal vaccines
• Meningococcal vaccines
  

Pneumococcal Immunizations

These vaccines protect against Streptococcus pneumonia infection. Prevnar 13 (PCV13) is given to all infants as a four-dose series at 2, 4, 6, and 12-15 months of age. Children with sickle cell disease should also receive Pneumovax 23 (or PPSV23) at 2 to 5 years of age with a second dose five years later.

Adults 19 and older with sickle cell disease who have not received a pneumococcal conjugate vaccine (PCV) should receive a single dose of either Vaxneuvance (PCV15) or Prevnar 20 (PCV20). Those who get PCV15 should get one dose of PPSV23 at least one year later.

 Meningococcal Immunizations

All children need to be immunized against Neisseria meningitidis, but children with sickle cell disease receive these immunizations earlier. There are two ways to receive them: as part of routine infant vaccination (four doses at 2, 4, 6, and 12 months of age), or after 7 months of age (two doses).

This vaccine is called Menveo or Menactra (MCV4). It requires booster shots throughout life. In 2016, immunization against meningococcus type B was added to the recommendations and can be given as a two- or three-dose series starting at age 10.

Haemophilus Influenzae Type B

Immunization for Haemophilus is part of the routine immunizations in the first year of life (four doses). This immunization is called Hib and can be given in combination with other immunizations. It is recommended at 2, 4, 6, and 12-15 months of age.

Influenza

Immunization with the yearly influenza vaccine is recommended for most people 6 months and older, including everyone with sickle cell disease.

The first time someone under the age of 9 receives the influenza vaccine, two doses are required (at least four weeks apart). Afterward, only one dose is required each year. Because the vaccine changes, it must be given annually.

Flu season runs from about October to March. If you receive your influenza vaccine in January, you would need another one—as soon as it becomes available—to cover the new influenza season beginning in October.

Summary

People with sickle cell disease are at higher risk for infection. This is because the disease causes early damage to the spleen, which plays an important role in the body's immune response.

Immunization can help protect children and adults from developing serious infections. The CDC recommends all people with sickle cell disease receive recommended vaccines. Some vaccines should be given on a different schedule.

A Word From Verywell

These infections sound worrisome, but fortunately, immunizations have significantly decreased the risk. Healthcare providers also give penicillin to children with sickle cell disease from birth to age 5. This can help prevent bacterial infections, too.

If you have questions or concerns about these immunizations, please discuss them with your healthcare provider.