Optimizing Immunization in Pediatric Special Risk Groups
Optimizing Immunization in Pediatric Special Risk Groups
This article analyzes the current recommended practices and evidence in the immunization of pediatric 'special risk groups'. Special risk group patients are at higher risk of vaccine-preventable diseases and hence require additional strategies to maximize protection against these diseases. The special risk groups include those with an underlying chronic disease, some of whom are on immunosuppressive therapy to treat that condition. The article uses four special risk groups (acute lymphoblastic leukemia; preterm birth; juvenile idiopathic arthritis; and inflammatory bowel disease), to highlight the management considerations and potential vaccination strategies. The risks, benefits and timing of vaccination in the setting of immunosuppression require detailed discussion with treating clinicians, in particular the use of live-attenuated vaccines. The immunogenicity of vaccines in these special risk groups helps provide the evidence base for their immunization guidelines. Protection can include 'cocooning' (i.e., ensuring appropriate immunizations within the immediate family; e.g., varicella, influenza and pertussis vaccination). Improving timeliness and minimizing missed opportunities to vaccinate individuals with these special risk conditions will also optimize protection from vaccine-preventable diseases.
This article details the current evidence and recommended practices in the immunization of children and adolescents with special risks. These special risk groups may be defined as such owing to multiple factors including: the underlying chronic medical condition, therapies (including immunosuppressive drugs) and increased exposure to vaccine-preventable diseases (VPDs). Increased nosocomial exposure is often due to the required management of their condition, including prolonged hospitalization and frequent outpatient visits. The child's age will affect these risks, as will vaccination history prior to the onset of the underlying condition. These factors are detailed in Figure 1 and a number of specific special risk groups, (acute lymphoblastic leukemia [ALL], preterm birth, juvenile idiopathic arthritis [JIA], and inflammatory bowel disease [IBD]) will be used to highlight optimizing immunization strategies and address underlying chronic disease and therapy specific considerations (see Table 1). The framework of management outlined in this article can be applied to other special risk groups, including the immunization of hematopoietic cell transplant recipients, HIV and asplenia patients, which have recently been reviewed and include maximizing protection from VPDs such as invasive pneumococcal disease (IPD).
(Enlarge Image)
Figure 1.
Key factors contributing to increased risk of vaccine-preventable diseases.
VPD: Vaccine-preventable disease.
Optimizing immunogenicity of immunization in these special risk groups is an area of active research, as individuals with chronic medical conditions are usually excluded from prelicensure vaccine trials. The killed (inactivated) vaccines are safe and well tolerated, but additional doses may be required. There is also a requirement to develop an evidence base for vaccination with some of the newer vaccines (e.g., human papillomavirus [HPV] and increased valency [10- and 13-valent] pneumococcal conjugate vaccines) in these special risk groups. Internationally there are guidelines for special risk groups and their additional vaccination requirements. The translation of these guidelines into clinical practice needs to be improved if these vulnerable special risk populations are to be protected.
Abstract and Introduction
Abstract
This article analyzes the current recommended practices and evidence in the immunization of pediatric 'special risk groups'. Special risk group patients are at higher risk of vaccine-preventable diseases and hence require additional strategies to maximize protection against these diseases. The special risk groups include those with an underlying chronic disease, some of whom are on immunosuppressive therapy to treat that condition. The article uses four special risk groups (acute lymphoblastic leukemia; preterm birth; juvenile idiopathic arthritis; and inflammatory bowel disease), to highlight the management considerations and potential vaccination strategies. The risks, benefits and timing of vaccination in the setting of immunosuppression require detailed discussion with treating clinicians, in particular the use of live-attenuated vaccines. The immunogenicity of vaccines in these special risk groups helps provide the evidence base for their immunization guidelines. Protection can include 'cocooning' (i.e., ensuring appropriate immunizations within the immediate family; e.g., varicella, influenza and pertussis vaccination). Improving timeliness and minimizing missed opportunities to vaccinate individuals with these special risk conditions will also optimize protection from vaccine-preventable diseases.
Introduction
This article details the current evidence and recommended practices in the immunization of children and adolescents with special risks. These special risk groups may be defined as such owing to multiple factors including: the underlying chronic medical condition, therapies (including immunosuppressive drugs) and increased exposure to vaccine-preventable diseases (VPDs). Increased nosocomial exposure is often due to the required management of their condition, including prolonged hospitalization and frequent outpatient visits. The child's age will affect these risks, as will vaccination history prior to the onset of the underlying condition. These factors are detailed in Figure 1 and a number of specific special risk groups, (acute lymphoblastic leukemia [ALL], preterm birth, juvenile idiopathic arthritis [JIA], and inflammatory bowel disease [IBD]) will be used to highlight optimizing immunization strategies and address underlying chronic disease and therapy specific considerations (see Table 1). The framework of management outlined in this article can be applied to other special risk groups, including the immunization of hematopoietic cell transplant recipients, HIV and asplenia patients, which have recently been reviewed and include maximizing protection from VPDs such as invasive pneumococcal disease (IPD).
(Enlarge Image)
Figure 1.
Key factors contributing to increased risk of vaccine-preventable diseases.
VPD: Vaccine-preventable disease.
Optimizing immunogenicity of immunization in these special risk groups is an area of active research, as individuals with chronic medical conditions are usually excluded from prelicensure vaccine trials. The killed (inactivated) vaccines are safe and well tolerated, but additional doses may be required. There is also a requirement to develop an evidence base for vaccination with some of the newer vaccines (e.g., human papillomavirus [HPV] and increased valency [10- and 13-valent] pneumococcal conjugate vaccines) in these special risk groups. Internationally there are guidelines for special risk groups and their additional vaccination requirements. The translation of these guidelines into clinical practice needs to be improved if these vulnerable special risk populations are to be protected.