Immunization of persons with chronic diseases: Canadian Immunization Guide

For health professionals

Notice

This chapter has not yet been updated with the following guidance from the National Advisory Committee on Immunization (NACI):

• May 15, 2025: NACI rapid response: Updated guidance on the use of Imvamune^® for the prevention of mpox (PDF)
• May 24, 2024: Interim guidance on the use of Imvamune^® in the context of a routine immunization program

Last partial content update: October 2026

This chapter has been updated to include guidance on COVID-19 vaccines and guidance from the following statements from the National Advisory Committee on Immunization (NACI):

• April 10, 2026: Updated guidance to protect infants and children from respiratory syncytial virus (RSV) disease: Use of monoclonal antibodies (nirsevimab and clesrovimab) and the RSVpreF vaccine (PDF)
• April 10, 2026: Updated guidance on respiratory syncytial virus (RSV) vaccines for older adults and for adults at high risk of severe RSV disease (PDF)
• March 13, 2025: Updated guidance on RSV vaccines for older adults including expanded use of RSVPreF3 for individuals 50 to 59 years of age and use of the new mRNS-1315 vaccine
• May 14, 2025: Updated recommendations on herpes zoster vaccination for adults who are immunocompromised (PDF)
• November 15, 2024: Recommendations on the use of pneumococcal vaccines in adults, including PNEU-C-21

This information is captured in the table of updates.

Last complete chapter revision: May 2022

On this page

• Introduction
• Chronic diseases
  • Asplenia or hyposplenia
  • Autoimmune conditions
  • Cancer
  • Cochlear implants
  • Endocrine and metabolic diseases
  • Heart disease
  • Hematologic disorders (non-malignant)
    • Anemia and hemoglobinopathy
    • Bleeding disorders
  • Kidney disease and people on dialysis
  • Liver disease
  • Lung disease
  • Neurologic disorders
  • Salicylate therapy
• Co-morbidities
• Close contacts
• Table 1: Vaccination of persons with chronic diseases: Non-live vaccines
• Table 2: Vaccination of persons with chronic diseases: Live attenuated vaccines
• Chapter revision methodology
• Acknowledgments
• Selected references

Introduction

Chronic diseases may increase a person's risk of infection, or increase a person's risk of more severe disease should infection occur. There is also an increased risk of nosocomial exposure to vaccine-preventable diseases due to the increased likelihood of prolonged hospitalization and frequent outpatient visits associated with chronic disease. Therefore, it is important that people with chronic diseases who are immunocompetent be immunized with both live and non-live (e.g., inactivated or recombinant) vaccines, according to routine immunization schedules. Vaccines may be less immunogenic in this population and additional vaccines, additional doses, or higher dosages of vaccines may be required to provide adequate protection.

If a disease progresses or immunosuppressive therapy is required, vaccine requirements and recommendations may change.

In general, individuals with chronic diseases are at higher risk of invasive pneumococcal disease, influenza and influenza-related complications, severe COVID-19 disease, and severe respiratory syncytial virus (RSV) disease, and should be immunized using the recommended vaccine and schedule, or for infants, RSV monoclonal antibodies.

For information about vaccination of people with immunodeficiencies, who are immunosuppressed, who have had a hematopoietic stem cell or solid organ transplant or have HIV infection, refer to Immunization of immunocompromised persons in Part 3.

Chronic diseases

Asplenia or hyposplenia

Asplenic or hyposplenic people have absent or defective splenic function. This condition can occur as a result of congenital absence of the spleen, surgical removal of the spleen, or medical conditions that result in poor or absent splenic function, such as sickle cell disease or thalassemia major, among others. All people, regardless of age, who have absent or defective splenic function, are at increased risk of fulminant bacteremia, which is associated with a high mortality rate. Risk is highest in the first 2 years following splenectomy but remains elevated for life.

Careful attention should be paid to immunization status when elective surgical splenectomy is planned so that all of the necessary vaccines are administered at least 2 weeks before surgery. In the case of an emergency splenectomy, vaccines are best given 2 weeks after the splenectomy for optimal vaccine responses. If a person is discharged earlier and there is a concern about returning for follow-up appointments, vaccines should be given before discharge.

Persons with functional or anatomic asplenia or hyposplenia should receive all routine vaccines, including annual influenza vaccine. In addition, particular attention should be paid to ensuring that all asplenic or hyposplenic individuals receive Haemophilus influenzae type b (Hib) regardless of age or previous immunization history, quadrivalent conjugate meningococcal vaccine, serogroup B meningococcal vaccine and pneumococcal conjugate (Pneu-C-20 or Pneu-C-21 depending on age) vaccine, as these individuals are highly susceptible to infection with encapsulated bacteria. Hepatitis B vaccines are indicated for those who require repeat transfusions, such as individuals with sickle cell anemia or thalassemia.

Refer to Table 1, Table 2 and to Influenza vaccines, Haemophilus influenzae type B vaccines, Meningococcal vaccines, Pneumococcal vaccines, and Hepatitis B vaccines in Part 4 for additional information.

Autoimmune conditions

Autoimmune conditions (referred to in former versions of the CIG as inflammatory diseases) encompass a broad category of related diseases in which the immune system is active against the body’s own cells. The spectrum of autoimmune conditions is diverse. The degree of autoimmunity in individuals with autoimmune conditions is variable depending on the underlying condition, the severity and progression of disease, and the use of medications that impact immune function. Common autoimmune conditions include systemic inflammatory diseases such as systemic lupus erythematosus, systemic vasculitides, rheumatoid arthritis; as well as such as Crohn's disease and ulcerative colitis, multiple sclerosis, myasthenia gravis, Goodpasture's syndrome, pemphigus vulgaris, psoriasis, idiopathic thrombocytopenic purpura and, autoimmune hemolytic anemia.

Infections are among the most common causes of morbidity, hospitalization and death in individuals with an autoimmune condition. An increased risk of infection and infection-related complications is thought to be due to both an altered immune response associated with the autoimmune condition itself and to the immunosuppressive nature of the treatments required to control the underlying inflammatory condition.

Individuals with autoimmune disease not being treated with immunosuppressive drugs are not considered significantly immunocompromised and can receive routine immunization, including live vaccines. Rheumatic disease modifying agents, such as hydroxychloroquine, sulfasalazine, or auranofin are not generally identified as immunosuppressive, nor are topically-administered formulations of steroids. For children receiving chronic salicylate therapy for autoimmune conditions, inactivated influenza vaccine (IIV) rather than live attenuated influenza vaccine (LAIV) should be used (refer to Salicylate therapy in children).

Individuals with autoimmune conditions and diabetes (type 1 and type 2) should receive, in addition to routine immunization, influenza and COVID-19 vaccine annually. Vaccination status should be assessed promptly and routine immunizations updated if needed. If immunosuppressive therapy is anticipated in the near future, Pneu-C-20 or Pneu-C-21 vaccine should be given, with a dose schedule that considers age and pneumococcal vaccine history. Because of immunodeficiencies associated with autoimmune inflammatory disease, some experts recommend giving these vaccines at diagnosis.

For individuals with dermatologic disorders, care should be taken not to administer vaccine into affected areas, as this procedure may exacerbate the condition. Bacille Calmette-Guérin (BCG) vaccine is contraindicated if there is extensive skin disease at or near the site of injection.

For individuals with chronic inflammatory diseases who are being treated with immunosuppressive therapies including biologic response modifiers, refer to Immunization of immunocompromised persons, Immunosuppressive therapy in Part 3.

Refer to Table 1, Table 2 and to Pneumococcal vaccines, COVID-19 vaccines, and Influenza vaccines in Part 4 for additional information.

Cancer

People with cancer have a higher risk of contracting infectious diseases and a higher risk of developing complications because many cancers and their treatments affect the immune system. Therefore, it is important that children and adults with cancer receive protection from vaccine preventable diseases whenever possible.

Generally, cancer alone, if it is not hematologic, is not sufficient to cause immunosuppression to the extent that an individual cannot receive live vaccines. If chemotherapy is not required, all routine vaccines should be given. Influenza and COVID-19 vaccines should be given annually. Other vaccines may be indicated, depending on which organs or systems are affected by the tumour. If chemotherapy is to be given, any immunizations required, as well as annual influenza vaccine, should be completed before beginning chemotherapy whenever possible.

For hematologic cancers or for people on immunosuppressive therapies, refer to Immunization of immunocompromised persons, Immunosuppressive therapy in Part 3.

Cochlear implants

People who have received a cochlear implant are at increased risk for bacterial meningitis and for otitis media. In addition to all age appropriate vaccinations, people with cochlear implants and those who are receiving cochlear implants should receive annual influenza vaccine, pneumococcal conjugate (Pneu-C-20 or Pneu-C-21 depending on age) vaccine, and Hib vaccine if 5 years of age or older regardless of Hib vaccination history.

Refer to Influenza vaccines, Pneumococcal vaccines, and Haemophilus influenzae type B vaccines in Part 4 for additional information.

Endocrine and metabolic diseases

People with diabetes mellitus have defects in phagocytic and neutrophil function. In addition, they often have complications of diabetes such as cardiovascular, neurovascular, renal and other end-organ dysfunction and are at greater risk of complications from infection. Persons with other metabolic disorders, such as thyroid disorders, or morbid obesity (Body Mass Index of 40 or higher) are at high risk of influenza-related complications.

Routine immunization, including annual influenza and COVID-19 vaccine, is important for persons with endocrine (e.g., diabetes) and other metabolic disorders. In addition to routine immunization, people with diabetes should receive pneumococcal conjugate (Pneu-C-20) vaccine if they are less than 18 years of age. Adults 18 years of age and older should receive one dose of Pneu-C-20 or Pneu-C-21 regardless of their pneumococcal vaccination history with Pneu-C-13, Pneu-C-15 or Pneu-P-23. A single dose of RSV vaccine is also particularly important for adults 65 years of age and older with diabetes and other metabolic disorders including obesity (defined as BMI of 40 kg/m2 and over). A single dose of RSV vaccine may be considered by adults 18 to 64 years of age at increased risk of severe RSV disease and who are not among the recommended groups for publicly funded vaccine programs, following discussion with their health care provider. There is no evidence that vaccination interferes with glycemic control.

There is an association between yellow fever vaccine-associated viscerotropic disease and a history of thymus disease. Yellow fever vaccine is contraindicated in persons with a history of thymus disease associated with abnormal thymus function (e.g., thymoma, thymectomy or myasthenia gravis). If travelling to a yellow fever endemic or epidemic area, expert advice should be sought concerning the risks of exposure to yellow fever, the ability to adhere to mosquito protection measures, and the risk of vaccine-associated disease.

Refer to Influenza vaccines, Pneumococcal vaccines, and Respiratory syncytial virus (RSV) vaccines in Part 4 and Table 1 for additional information.

Heart disease

In individuals with chronic heart disease, viral and bacterial infections may precipitate cardiac decompensation and lead to hospitalization. There is evidence that giving influenza vaccine to those with coronary artery disease has some protective effect on subsequent cardiac events.

People with cardiac disease should receive routine immunization, including COVID-19 vaccine and annual influenza vaccine, as they are at high risk of complications. Children 2 months to less than 18 years of age with chronic heart disease should also receive pneumococcal conjugate vaccine (Pneu-C-20). Adults less than 50 years of age with chronic heart disease may be considered for pneumococcal conjugate vaccination with Pneu-C-15 or Pneu-C-20 at clinical discretion.

Young children with certain chronic cardiac conditions are at high risk of RSV associated hospitalization. RSV monoclonal antibodies, are recommended to protect against severe infection in infants with chronic heart disease during their first and second RSV season. RSV vaccine is particularly important for adults 65 years of age and older with chronic cardiac disease. A single dose of RSV vaccine may be considered by adults 18 to 64 years of age at increased risk of severe RSV disease and who are not among the recommended groups for publicly funded vaccine programs, following discussion with their health care provider.

Refer to Table 1, Table 2 and to Influenza vaccines, COVID-19 vaccines, Pneumococcal vaccines, and Respiratory syncytial virus (RSV) vaccines in Part 4 for additional information.

Hematologic disorders (non-malignant)

Non-malignant hematologic disorders include different types of chronic anemia and hemoglobinopathy, as well as bleeding disorders. For further discussion on vaccines recommended for people with anemia due to sickle cell disease or other hemoglobinopathies associated with splenic dysfunction, refer to Asplenia or hyposplenia.

Some hematologic disorders require frequent or chronic administration of blood products. Recent administration of blood products may interfere with the antibody response to live vaccines, and receipt of plasma or immunoglobulin may result in false positive antibody tests. Refer to Blood products, human immunoglobulin and timing of immunization in Part 1 for additional information.

Anemia and hemoglobinopathy

People with anemia may be at increased risk of complications from vaccine preventable diseases. In addition to routine immunization, people with chronic anemia or hemoglobinopathy should receive influenza vaccine annually. If there is a need for repeated blood transfusions, hepatitis B vaccine is required. If there is splenic dysfunction, refer to Asplenia and hyposplenia.

Refer to Table 1, Table 2 and to Influenza vaccines, and Hepatitis B vaccines in Part 4 for additional information.

Bleeding disorders

People with bleeding disorders such as hemophilia may differ from the healthy population with respect to the potentially increased risk of infection as a result of exposure to blood products and the risk of hematoma formation from parenteral injections. In addition to routine immunization, people with hemophilia and other clotting factor disorders receiving repeated transfusions of blood or blood products should receive hepatitis B vaccines unless already infected or immune. Pre-immunization serologic testing for hepatitis B should be performed if they have already had repeated exposure to blood products. In addition, those receiving repeated infusions of plasma-derived clotting factors should receive hepatitis A vaccine.

Before beginning immunization of any child, vaccine providers should ensure that there are no symptoms or signs compatible with an undiagnosed bleeding disorder. If such indicators are present, a diagnosis should be established before commencing immunization. For example, in any child who has a history of an intramuscular (IM) hematoma following an IM injection, an undiagnosed bleeding disorder, such as hemophilia, should be considered. If a disorder is present, it should be optimally managed prior to immunization to minimize the risk of bleeding. Hemophiliacs may receive clotting factor concentrates to optimize their clotting factor level before they receive a parenteral vaccine or a passive immunizing agent.

Generally, there is no evidence of increased risk of bleeding in those with bleeding disorders following IM versus subcutaneous injections. There is evidence to suggest that IM administration is safe when given with a small gauge needle (23 gauge or smaller) and when firm pressure is applied to the injection site for ≥ 2 minutes. There is also evidence that immunization by the subcutaneous route for vaccine intended for intramuscular administration may be associated with more local reactogenicity and a diminished immune response, compared to the IM route. Individuals receiving long-term anticoagulation may also be safely immunized through either the IM or subcutaneous route as recommended for a specific vaccine, using the same precautions as for bleeding disorders, without discontinuation of their anticoagulation therapy.

Refer to Table 1, Table 2 and to Influenza vaccines, Hepatitis A vaccines and Hepatitis B vaccines in Part 4 for additional information.

Kidney disease and people on dialysis

Bacterial and viral infections are a major cause of morbidity and mortality in people with renal disease or who are undergoing chronic dialysis (hemodialysis or peritoneal dialysis). People with chronic kidney insufficiency and dialysis may have mild defects in T cell function, while in individuals with nephrotic syndrome, lose antibody in the urine. Also, because people with kidney disease and people on dialysis are in frequent contact with the health care system, they are at greater risk of hospital-acquired infection from vaccine preventable diseases.

People with chronic renal disease or those who are undergoing dialysis should receive all routine vaccinations, including annual influenza and COVID-19 vaccine. In addition to routine immunizations, hepatitis B and pneumococcal conjugate vaccines (Pneu-C-20 or Pneu-C-21 depending on age) are recommended. For individuals with chronic renal disease, a higher dose of monovalent HB vaccine is recommended (refer to Hepatitis B vaccines in Part 4 for information on a higher vaccine dose). Pneu-C-20 or Pneu-C-21 (depending on age) is also recommended for individuals with nephrotic syndrome. RSV vaccine is particularly important for adults 65 years of age and older with chronic renal disease. A single dose of RSV vaccine may be considered by adults 18 to 64 years of age at increased risk of severe RSV disease, following discussion with their health care provider. Since individuals with impaired renal function may experience a less than optimal response to immunization, higher vaccine doses and re-immunization may be required. Monitoring vaccine titers may be helpful.

For information about kidney transplant candidates and recipients, refer to Immunization of immunocompromised persons, Solid organ transplantation in Part 3.

Refer to Table 1, Table 2 and to Influenza vaccines, COVID-19 vaccines, Respiratory syncytial virus (RSV) vaccines, Hepatitis B vaccines, and Pneumococcal vaccines in Part 4 for additional information.

Liver disease

Chronic liver disease can impact innate and adaptive immune mechanisms. Splenic dysfunction may also occur if the liver disease is severe. Hepatic encephalopathy or chronic alcohol consumption may lead to aspiration pneumonia. People with an alcohol use disorder are also at risk for invasive pneumococcal disease. Newly acquired hepatitis A or hepatitis B in persons who already have chronic liver disease from another cause could lead to more severe disease and rapid hepatic decompensation. Those with ascites have altered immunoglobulin production and distribution.

People with chronic liver disease, including hepatic cirrhosis and biliary atresia, should receive all routine immunizations, including annual influenza vaccine, COVID-19 vaccine, conjugate pneumococcal vaccine (Pneu-C-20 or Pneu-C-21 depending on age), as well as hepatitis A vaccine and hepatitis B vaccine. RSV vaccine is particularly important for adults 65 years of age and older with chronic liver disease. A single dose of RSV vaccine may be considered by adults 18 to 64 years of age at increased risk of severe RSV disease following discussion with their health care provider. Vaccination should be completed early in the course of liver disease, as the immune response to vaccine is suboptimal in advanced liver disease. Consideration should be given to offering a higher vaccine dose to individuals with advanced liver disease who do not demonstrate an adequate anti-HBs titre following initial immunization series (refer to Hepatitis B vaccines in Part 4 for information on a higher vaccine dose). Since individuals with chronic liver disease may experience a less than optimal response to immunization, higher vaccine doses and re-immunization may be required.

Refer to Table 1, Table 2 and to Influenza vaccines, COVID-19 vaccines, Pneumococcal vaccines, Respiratory syncytial virus (RSV) vaccines, Hepatitis A vaccines, and Hepatitis B vaccines in Part 4 for additional information.

Lung disease

Individuals with chronic lung diseases such as bronchopulmonary dysplasia, cystic fibrosis, pulmonary fibrosis, asthma or chronic obstructive pulmonary diseases (COPD) are at increased risk of complications of influenza, COVID-19, RSV and pneumococcal infection. Those with cystic fibrosis are also at increased risk of complications from varicella infection. Infants and young children with chronic lung disease, requiring ongoing assisted ventilation, oxygen therapy or chronic medical therapy in the six months prior to the start of the RSV season, are at high risk for hospitalization due to severe RSV disease and invasive pneumococcal disease.

People with chronic lung disorders should receive influenza and COVID-19 vaccine annually in addition to other routine immunization. Live attenuated influenza vaccine (LAIV) is contraindicated for persons with current severe asthma (currently on oral or high dose inhaled glucocorticosteroids or active wheezing, or those with medically attended wheezing in the seven days prior to immunization). In these situations, non-live influenza vaccine should be used. Pneumococcal vaccines are also recommended, including for those with asthma requiring medical care in the preceding 12 months. For people with chronic lung disease, Pneu-C-20 vaccine should be given if age less than 18 years. Adults 18 years of age or older with chronic lung disease should receive one dose of Pneu-C-20 or Pneu-C-21 regardless of their pneumococcal vaccination history with Pneu-C-13, Pneu-C-15 or Pneu-P-23. RSV monoclonal antibodies are recommended to protect against severe RSV infection in children with chronic lung disease, during their first and second RSV season. RSV vaccine is particularly important for adults 65 years of age and older with pulmonary disorders including chronic obstructive pulmonary disease (COPD), asthma, and conditions affecting ability to clear airway secretions. A single dose of RSV vaccine may be considered by adults 18 to 64 years of age at increased risk of severe RSV disease, following discussion with their health care provider.

Refer to Table 1, Table 2 and to Influenza vaccines, COVID-19 vaccines, Pneumococcal vaccines, and Respiratory syncytial virus (RSV) vaccines in Part 4 for additional information.

Refer to Immunization of immunocompromised persons in Part 3 for additional information about vaccination of individuals receiving systemic steroids or other immunosuppressive therapy for their lung disease, as well for vaccination of lung transplant candidates and recipients.

Neurologic disorders

Persons with neurological disorders are at increased risk of hospitalization with influenza. Some studies suggest that influenza vaccine may also decrease the risk of stroke.

In addition to all routine immunizations, people with neurological or neurodevelopmental conditions should receive annual influenza and COVID-19 vaccine. Pneumococcal vaccines are recommended for those with chronic cerebrospinal fluid (CSF) leak and for those who have or difficulty clearing respiratory secretions. Those less than 18 years of age should receive pneumococcal conjugate (Pneu-C-20) vaccine. Adults 18 years of age and older with chronic neurologic conditions that impair clearance of oral secretions should receive one dose of Pneu-C-20 or Pneu-C-21 regardless of their pneumococcal vaccination history with Pneu-C-13, Pneu-C-15 or Pneu-P-23. Children with neuromuscular disease that impairs clearing of respiratory secretions are at increased risk for severe RSV disease and should receive RSV monoclonal antibodies during their first and second RSV season. RSV vaccine is particularly important for adults 65 years of age and older with neurologic or neurodevelopmental conditions including neuromuscular, neurovascular, neurodegenerative (e.g., dementia), neurodevelopmental conditions, and seizure disorders. A single dose of RSV vaccine may be considered by adults 18 to 64 years of age at increased risk of severe RSV disease following discussion with their health care provider.

Certain neurologic disorders (e.g., multiple sclerosis), may be treated with immunosuppressive therapies. In this situation, recommendations for immunocompromised persons should be applied. For information, refer to Immunization of immunocompromised persons in Part 3.

Refer to Table 1, Table 2 and to Influenza vaccines, Respiratory syncytial virus (RSV) vaccines and Pneumococcal vaccines in Part 4 for additional information.

Salicylate therapy

Manufacturers of varicella-containing vaccines recommend avoidance of salicylate therapy (medications derived from salicylic acid, such as ASA) for 6 weeks after varicella immunization because of an association between wild-type varicella, salicylate therapy and Reye's syndrome.

Health care providers should weigh the theoretical risks associated with varicella vaccine against the known risks associated with wild-type varicella infection. Because adverse events have not been reported with the use of salicylates after varicella immunization, people with conditions requiring chronic salicylate therapy should be considered for immunization, with close subsequent monitoring.

Children and adolescents receiving chronic salicylate therapy are at high risk of influenza-related complications and should receive inactivated influenza vaccine annually (IIV). LAIV should not be administered to children currently receiving ASA.

Refer to Influenza vaccines and Varicella (chickenpox) vaccines in Part 4 for additional information.

Co-morbidities

Guidance on immunization for those with more than one chronic condition is an emerging area of inquiry; evidence to support guidance on immunization of people with co-morbidities is lacking. There is some evidence that co-morbidities may have additive risk for complications from vaccine preventable diseases, such as influenza, COVID-19, and RSV. As a general principle, when considering immunization of people with co-morbidities, all conditions and medications should be considered in relation to the indications, precautions and contraindications for each vaccine.

Close contacts

Annual influenza vaccine and up-to-date routine immunizations are recommended for household members and other close contacts of people with chronic diseases, as well as for their health care workers.

Family members of those with chronic diseases or those who are immunocompromised can receive routine live vaccines.

Refer to Immunization of workers and Immunization of immunocompromised persons in Part 3 for additional information.

Table 1: Vaccination of persons with chronic diseases: Non-live vaccines

Please note that the information in the text and tables is complementary and both should be used.

Refer to vaccine-specific chapters in Part 4 for additional information, especially concerning vaccine doses, schedules and boosters.

Table 2: Vaccination of persons with chronic diseases: Live attenuated vaccines

Please note that the information in the text and tables is complementary and both should be used.

Refer to vaccine-specific chapters for additional information, especially concerning vaccine doses, schedules and boosters.

Chapter revision methodology

Updates were made to reflect recent NACI guidance on the use of RSV vaccines and monoclonal antibodies for the prevention of severe RSV disease in people with certain chronic diseases, use of herpes zoster (shingles) vaccine in adults who are immunocompromised, use of pneumococcal vaccines (including PNEU-C-21) in adults with chronic diseases, and COVID-19 vaccination of persons with chronic diseases. Table 1, that outlines recommendations for the use of non-live vaccines for persons with chronic diseases, was also updated to reflect changes.

Acknowledgements

Recent updates were prepared by A Nunn and N Mohamed and reviewed by E Abrams, O Baclic, M Salvadori and C Jensen.

NACI gratefully acknowledges the contributions of C Tremblay.

Selected references

General references

• American Academy of Pediatrics. Immunization in special clinical circumstances. In: Kimberlin DW, Brady MT, Jackson MA, Long SS (eds) Red Book: 2018 Report of the Committee on Infectious Diseases. 31st ed. Itasca, IL: American Academy of Pediatrics; 2018. pp 67-111.
• Committee to Advise on Tropical Medicine and Travel. The immunocompromised traveller. Can Commun Dis Rep 2007;33(ACS-4):1-24. Accessed June 28, 2021
• Crawford NW, Bines JE, Royle J et al. Optimizing immunization in pediatric special risk groups. Expert Rev Vaccines 2011;10:175-86.
• Kroger A, Bahta L, Hunter P Kroger AT, Duchin J, Vázquez M. General best practice guidelines for immunization. Best practices guidance of the Advisory Committee on Immunization Practices (ACIP). Updated May 4, 2021.https://www.cdc.gov/vaccines/hcp/acip-recs/general-recs/index.html Accessed May 21, 2021
• Lail J, Fields E, Schoettker PJ. Quality improvement strategies for population management of children with medical complexity. Pediatrics. 2017;140(3):e20170484
• Lobermann et al. Immunization in the adult immunocompromised host. Autoimmunity Reviews 2012;11:212-218
• Lopez et al. Vaccination recommendations for the adult immunosuppressed patient: A systematic review and comprehensive field synopsis. J. Autoimmunity 2017: 80:10-27.

Asplenia, hyposplenia

• Di Sabatino A, Carsetti R, Corazza GR. Post-splenectomy and hyposplenic states. Lancet 2011; 378: 86–97.
• Kuchar E, Miskiewicz K, Karlikowska M. A review of guidance on immunization in persons with defective or deficient splenic function. Br J Haemat 2015;171:683–694.
• Simons MD, Scott-Sheldon LAJ, Risech-Neyman Y et al. Celiac disease and increased risk of pneumococcal infection: A systematic review and meta-analysis. Am J Med 2018;131:83–89.
• Theilacker C, Ludewig K, Serr A. Overwhelming postsplenectomy infection: A prospective multicenter cohort study. Clin Infect Dis. 2016 62(7):871-878.
• Tjernberg AR, Bonnedahl J, Inghammar M. Coeliac disease and invasive pneumococcal disease: a population-based cohort study. Epidemiol. Infect. (2017), 145, 1203–1209.

Autoimmune conditions

• Bombardier C, Hazlewood GS, Akhavan P, et al. Canadian Rheumatology Association recommendations for the pharmacological management of rheumatoid arthritis with traditional and biologic disease-modifying antirheumatic drugs: Part II. Safety. J Rheumatol 2012 Aug;39(8):1583-602.
• Chaudrey K, Salvaggio M, Ahmed A, Mahmood S, Ali T. Updates in vaccination: recommendations for adult inflammatory bowel disease patients. World J Gastroenterol 2015; 21(11): 3184-3196.
• Furer V, Rondaan C, Heijstek MW et al. 2019 update of EULAR recommendations for vaccination in adult patients with autoimmune inflammatory rheumatic diseases Ann Rheum Dis. 2020 Jan;79(1):39-52.
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• Heijstek MW, Ott de Bruin LM, Bijl M, EULAR recommendations for vaccination in paediatric patients with rheumatic diseases. Ann Rheum Dis 2011;70:1704–1712.
• Kantso B, Simonsen J,Hoffmann S. Inflammatory bowel disease patients are at increased risk of invasive pneumococcal disease: A nationwide Danish cohort study 1977–2013. Am J Gastroenterol 2015; 110:1582–1587
• Luijten RKMAC, Cuppen BVJ, Bijlsma JWJ, Derksen RHWM. Serious infections in systemic lupus erythematosus with a focus on pneumococcal infections. Lupus (2014) 23, 1512–1516.
• McCarthy EM, Azeez MA, Fitzpatrick FM et al. Knowledge, Attitudes and clinical practice of rheumatologists in vaccination of the at risk rheumatology patient population. J Clin Rheum 2012;18:237-41.
• Morin MP, Quach C, Fortin E et al. Vaccination coverage in children with juvenile idiopathic arthritis followed at a paediatric tertiary care centre. Rheumatology 2012;276-90.

Bleeding disorders

• Bauman ME, Hawkes M, Bruce A, Siddons S, Massicotte P. Immunizations in children requiring warfarin therapy. J Pediatr Hematol Oncol 2016;38:e329–e332.
• Casajuana J, Iglesias B, Fabregas M et al. Safety of intramuscular influenza vaccine in patients receiving oral anticoagulation therapy: a single blinded multi-centre randomized controlled clinical trial. BMC Blood Disord 2008;8:1-7. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2423363/
• Evans D I K, Shaw A. Safety of intramuscular injection of hepatitis B vaccine in haemophiliacs. BMJ 1990;300:1694-5
• Kroger A, Bahta L, Hunter P. General Best Practice Guidelines for Immunization. Best Practices Guidance of the Advisory Committee on Immunization Practices (ACIP). Vaccinating Persons with Increased Bleeding Risk p159-160. [www.cdc.gov/vaccines/hcp/acip-recs/general-recs/downloads/general-recs.pdf]. Accessed on May 21, 2021
• Raj G, Kumar R, McKinney WP. Safety of intramuscular influenza immunization among patients receiving long-term warfarin anticoagulation therapy. Arch Intern Med.1995;155:1529-1531
• van Aalsburg R, van Genderen PJ. Vaccination in patients on anticoagulants. Travel Med Infect Dis 2011;9: 310-11.

Kidney disease

• Esposito S, Mastrolia MV, Prada E, Pietrasanta C, Principi N. Vaccine administration in children with chronic kidney disease. Vaccine. 2014 Nov 20;32(49):6601-6.
• Mathew R, Mason D, Kennedy JS. Vaccination issues in patients with chronic kidney disease.Expert Rev Vaccines. 2014 Feb;13(2):285-98.
• Soni R, Horowitz B, Unruh M. Immunization in end-stage renal disease: opportunity to improve outcomes. Semin Dial. 2013 Jul-Aug;26(4):416-26.

Other conditions

• Centers for Disease Control and Prevention. Use of hepatitis B vaccination for adults with diabetes mellitus: Recommendations of the Advisory Committee on Immunization Practices (ACIP). MMWR, 2011;60(50):1709-1711.
• Langer-Gould A, Qian L, Tartof SY. Vaccines and the risk of multiple sclerosis and other central nervous system demyelinating diseases JAMA Neurol. 2014;71(12):1506-1513
• Natarajan P, Cannon CP. Myocardial infarction vaccine? Evidence supporting the influenza vaccine for secondary prevention. Eur Heart J 2011;32:1701-03.
• Schanzer DL, Langley JM, Tam TW. Co-morbidities associated with influenza-attributed mortality, 1994-2000, Canada. Vaccine. 2008 Aug 26;26(36):4697-703.