Pneumococcal Vaccination Rates in Children With Sickle Cell Disease Alecia C. Nero, MD; Kwei Akuete, MD, MPH; Sarah Leasure Reeves, MPH; Kevin J. Dombkowski, DrPH, MS rrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrr
Context: Sickle cell disease (SCD) confers an increased risk of invasive pneumococcal disease, especially among young children. Pneumococcal vaccination decreases this risk, but the completion rate of age-appropriate vaccinations is not well defined in SCD. Objective: The goal of this study was to assess whether pneumococcal vaccines are administered to high-risk children with SCD according to recommended vaccine schedules. Design: A case-control design was used to conduct this study. Setting: Administrative data were obtained on Michigan Medicaid or Children’s Special Health Care Services programs enrollees. In addition, Michigan Newborn Screening and Michigan Care Improvement Registry records were used to confirm diagnosis and vaccine administration. Participants: This study compared pneumococcal vaccination rates in a cohort of 179 children with SCD with 537 age-matched non-SCD controls (1:3) enrolled in the Michigan Medicaid Program between 2001 and 2008. Study subjects were born in the state of Michigan between 2001 and 2005. Main Outcome Measure: The main outcome measure was the proportion of children defined as up to date for pneumococcal vaccines at defined milestone ages. Results: Children with SCD had significantly higher vaccination rates than controls, yet these values were much lower than state and national immunization survey rates. Conclusion: Barriers to completing age-appropriate recommended pneumococcal immunizations should be identified and addressed to further reduce invasive pneumococcal disease in this high-risk patient population. KEY WORDS: invasive pneumococcal disease, pneumococcal
vaccine, sickle cell disease
Sickle cell disease (SCD) affects nearly 100 000 persons in the United States and millions worldwide.1 Functional asplenia in infancy2 renders these children highly susceptible to invasive Streptococcus pneumoniae infection, particularly between the ages of 1 and 3 years.3,4 The risk of invasive pneumococcal disease (IPD) in SCD is estimated at 300 times the general population5 and overall death rate 100 times higher than normal.6 Invasive pneumococcal disease is determined when the bacteria are isolated from a sterile site (such as the blood or cerebrospinal fluid) or suspected invasive infection is documented in the medical record or on a death certificate.7 Accordingly, patients with SCD are identified as at high risk for IPD by the World Health Organization,8 the American Academy of Pediatrics,9 and the Centers for Disease Control and Prevention.10 Recent studies document that targeted and universal pneumococcal vaccination (PV) decreases IPD among children with SCD.5,6,11 The American Academy of Pediatrics Committee on Infectious Diseases outlines specific vaccine recommendations for these highrisk patients to include the complete pneumococcal protein–conjugate and polysaccharide vaccine series.12 Few data exist, however, regarding the degree to which children with SCD actually receive these recommended vaccinations in an age-appropriate manner. Author Affiliations: Departments of Internal Medicine and Pediatrics, Division of Hematology-Oncology, UT Southwestern Medical Center, Dallas, Texas (Dr Nero), Maryland Inpatient Care Specialist, Glen Burnie, Maryland (Dr Akuete); Department of Epidemiology, University of Michigan School of Public Health, Ann Arbor (Ms Reeves); and Department of Pediatrics, University of Michigan, Ann Arbor (Dr Dombkowski). The authors thank Drs George Buchanan and Timothy McCavit for encouragement and critical reading of the manuscript. They also thank Shiming Dong for statistical support, Sarah J. Clark, MPH, for contributions during the planning of this study, and the Michigan Department of Community Health for assistance with obtaining newborn screening data. None of the authors declare conflict of interest or source funding.
J Public Health Management Practice, 2014, 20(6), 587–590 C 2014 Wolters Kluwer Health | Lippincott Williams & Wilkins Copyright
Correspondence: Alecia C. Nero, MD, Departments of Internal Medicine and Pediatrics, Division of Hematology-Oncology, UT Southwestern Medical Center, 5323 Harry Hines Blvd, Dallas, TX 75390 ([email protected]). DOI: 10.1097/PHH.0000000000000034
587 Copyright © 2014 Lippincott Williams & Wilkins. Unauthorized reproduction of this article is prohibited.
588 ❘ Journal of Public Health Management and Practice The objective of this study was to assess whether children with SCD receive PV age-appropriately, comparing the completeness and timeliness of these vaccinations with their non-SCD counterparts.
● Methods This study assessed PV rates and timing, including both PCV7 (pneumococcal conjugate vaccine, Prevnar7) and PPV23 (pneumococcal polysaccharide vaccine, Pneumovax), in children with SCD using a case-control study design. This study was approved by the University of Michigan institutional review board.
Study population All SCD cases were enrolled in Michigan Medicaid or Children’s Special Health Care Services (CSHCS) programs between 2001 and 2008. They were born in Michigan during 2001-2005, following introduction of PCV7 into the US immunization schedule. For each case, 3 controls using a random sample of Medicaid beneficiaries were matched by birth month/year, race, and county. Medicaid eligibility and demographic characteristics were obtained for all children until 59 months of age from Medicaid administrative files.
SCD case classification The cases of SCD were classified as those having more than 3 SCD claims for inpatient, outpatient, or emergency department services or having SCD as a qualifying diagnosis for participation in CSHCS programs. It was defined to include sickle β-thalassemia, sickle cell anemia, sickle hemoglobin-C, and unspecified SCD represented by the following International Classification of Diseases, Ninth Revision, codes: (282.41, 282.42, 282.6, 282.60, 282.61, 282.62, 282.63, and 282.64). All other hemoglobinopathies were excluded. Cases meeting these criteria were subsequently verified through Michigan Newborn Screening records.
Outcomes measured The primary outcome assessed was the proportion of children up to date for PV at key milestone ages defined as at least 1 vaccine dose by 3 months, 2 doses by 5 months, and 3 doses by 7 months of age. Receipt of PV was identified in claims data using Current Procedural Terminology codes (PCV7: 90669; PPV23: 90732). Doses for “Streptococcus pneumoniae (pneumococcus)” without PCV7 or PPV23 designation were included using International Classification of Diseases, Ninth Revision, Clinical Modification, diagnosis codes (V0382, V066).
Vaccination records were obtained for cases and controls from the Michigan Care Improvement Registry, a population-based registry that automatically initiates a new record for children born in Michigan using inputs from electronic birth certificates. Michigan law requires that providers report all vaccinations administered to children into the Michigan Care Improvement Registry. Proportions were compared by the Fisher exact test for significance.
● Results A total of 235 children with SCD were identified and 179 (76%) were confirmed through newborn screening validation. Next, 537 controls (3:1) were matched to confirmed cases. By 3 months of age, 129 children with SCD (72%) and 322 without SCD (60%) were up to date with PV (Figure). By 5 months of age, 54% and 42% of children, respectively, were up to date, and by 7 months of age, 40% of cases and 24% of controls received at least 3 doses. At all ages, children with SCD had significantly higher rates of PV than controls (P < 0.01). Extending the age cutoff showed similar results, that is, the proportion of children receiving at least 3 doses increased substantially, reaching 73% with SCD and 54% without SCD by 24 months of age. Again, at least 4 doses were documented in 73% of children with SCD and 35% of children without SCD by 59 months of age. These data reflect significantly higher PV rates in children with SCD than in controls (Figure; P < .0001).
● Discussion Despite well-known risk of life-threatening IPD among children with SCD and documented decreased infection rates since availability of licensed vaccines, adherence to published recommendations remains poorly defined. Studies have evaluated IPD rates in SCD during the pneumococcal vaccine era but are often assessed after cases of IPD were identified.13,14 Documentation of age-appropriate PV in SCD helps assess the continued extent of undervaccination among this high-risk group. This cohort of high-risk children with SCD had higher PV rates than controls but were lower than the 2008 National Immunization Survey (NIS) data.15 The reported PV average rates for the state of Michigan and nationwide were nearly identical to each other at every age cutoff for that year. However, rates in the SCD cohort were lower at 3 months (72% vs 84%), 5 months (54% vs 74%), and 24 months (73% vs 92%) than these state/national rates. This suggests barriers to timely PV in our study population, prompting the need to
Copyright © 2014 Lippincott Williams & Wilkins. Unauthorized reproduction of this article is prohibited.
Pneumococcal Vaccination Rates in Children With Sickle Cell Disease
❘ 589
FIGURE ● PVa status, Children Younger Than 59 Months Born 2001-2005b
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Abbreviations: PV, pneumococcal vaccination; SCD, sickle cell disease; UTD, up to date (defined as the appropriate number of pneumococcal vaccines received by age reported in months). a PV includes PCV7 and/or PPSV23. b All group comparisons were statistically significant, P < .01.
better target obstacles that hinder age-appropriate immunizations in high-risk children with SCD. Caution should be taken when comparing data in this cohort with NIS data, since there were 2 periods of PCV7 vaccine shortages between 2001 and 2008, and official recommendations asked providers to withhold the third and fourth doses of PCV7 to healthy but not high-risk patients.16,17 This recommendation should favor vaccinations in children with SCD, therefore making the difference between the study population and NIS data even more concerning. There are several limitations of this study. First, the analysis included only children in the Michigan Medicaid or CSHCS databases, so generalizations to children with SCD nationally may not be appropriate. However, this sample is representative of the state, as approximately 75% of SCD cases are in the data warehouses that include Medicaid, CSHCS, or both. Second, the control group was well matched by demographics but may have included other high-risk individuals without SCD. Third, the clinical consequences of incomplete immunization status is unclear since patients with SCD can generate immunologic response even after 1 vaccine dose, similar to that of infants without disease.18 Therefore, incomplete PV may still provide some protection against IPD. Routine prophylactic antibiotic use, as well as herd immunity, may also contribute to lower risk of IPD in children with SCD.19 Fourth, our data do not distinguish immunization rates between PCV7 and PPV23 because of coding ambiguities. This may confound the results since PPV23 is not included in the primary series but recommended for high-risk children such as those with SCD after 2 years of age.12 The observed increased PV rates among older children may, therefore, reflect
PPV23 use rather than late administration of PCV7. In addition, national and state averages may be variable from year to year, which was not documented here. In conclusion, these data indicate that PV completion rates are lower than NIS survey state and national rates. Therefore, children with SCD may be at increased risk for fatal IPD. With better definition of barriers to age-appropriate PV rates in SCD, interventions can be offered to address these issues. Such strategies can include targeted provider and patient education to improve community outreach or provider use of state registries to help identify high-risk children. Other efforts may work to ensure adequate vaccine supply to areas lacking resources or engaging local and state agencies to implement regional-specific immunization programs.
REFERENCES 1. Hassell KL. Population estimates of sickle cell disease in the U.S. Am J Prev Med. 2010;38(4S):S512-S521. 2. Serjeant GR, Serjeant BE. Sickle Cell Disease. 3rd ed. New York, NY: Oxford University Press; 2001. 3. Wong WY, Overturf GD, Powars DR. Infection caused by Streptococcus pneumonia in children with sickle cell disease: epidemiology, immunologic mechanisms, prophylaxis, and vaccination. Clin Infect Dis. 1992;14(5):1124-1136. 4. Leikin SL, Gallagher D, Kinney TR, et al. Mortality in children and adolescents with sickle cell disease. Cooperative study of sickle cell disease. Pediatrics. 1989;84(3):500-508. 5. Adamkiewicz TV, Sarnaik S, Buchanan GR, et al. Invasive pneumococcal infections in children with sickle cell disease in the era of penicillin prophylaxis, antibiotic resistance, and 23valent pneumococcal polysaccharide vaccination. J Pediatr. 2003;143:438-444.
Copyright © 2014 Lippincott Williams & Wilkins. Unauthorized reproduction of this article is prohibited.
590 ❘ Journal of Public Health Management and Practice 6. McCavit TL, Xuan L, Zhang S, et al. Hospitalization for invasive pneumococcal disease in a national sample of children with sickle cell disease before and after PCV7 licensure. Pediatr Blood Cancer. 2012;58:945-949. 7. Centers for Disease Control and Prevention. Manual for the Surveillance of Vaccine-Preventable Diseases, 5th ed. Atlanta, GA: Centers for Disease Control and Prevention; 2008:chap 11. 8. World Health Organization. Pneumococcal vaccines: World Health Organization position paper. WHO Wkly Epidemiol Rec. 1999;74(23)150-151. 9. American Academy of Pediatrics. Red Book: 2009 Report of the Committee on Infectious Diseases. 28th ed. Chicago, IL: American Academy of Pediatrics; 2009. 10. Centers for Disease Control and Prevention. Epidemiology and Prevention of Vaccine-Preventable Diseases. 12th ed. Washington, DC: Public Health Foundation; 2011. 11. Ellison AM, Ota KV, McGowan KL, et al. Pneumococcal bacteremia in a vaccinated pediatric sickle cell disease population. Pediatr Infect Dis J. 2012;31:534-536. 12. American Academy of Pediatrics Committee on Infectious Diseases. Recommendations for the prevention of Streptococcus pneumoniae in infants and children: use of 13-valent pneumococcal conjugate vaccine (PCV13) and pneumococcal polysaccharide vaccine (PPSV23). Pediatrics. 2010;126(1): 186-190. 13. Halasa NB, Shankar SM, Talbot TR, et al. Incidence of invasive pneumococcal disease among individuals with
14.
15.
16.
17.
18.
19.
sickle cell disease before and after the introduction of the pneumococcal conjugate vaccine. Clin Infect Dis. 2007;44: 1428-1433. McCavit TL, Quinn CT, Techasaensiri C, Rogers ZR. Increase in invasive Streptococcus pneumonia infections in children with sickle cell disease since pneumococcal conjugate vaccine licensure. J Pediatr. 2011;158:505-507. Centers for Disease Control and Prevention. National Immunization Survey Tables. http://www.cdc.gov/vaccines/ stats-surv/nis/data/tables 2008.htm. Accessed February 4, 2011. Santoli JM, Peter G, Arvin AM, et al. Strengthening the supply of routinely recommended vaccines in the United States: recommendations from the National Vaccine Advisory Committee. JAMA. 2003;290(23):31223128. Centers for Disease Control and Prevention. Updated recommendations on the use of pneumococcal conjugate vaccine: suspension of recommendation for third and fourth dose. MMWR Morb Mortal Wkly Rep. 2004;53(8):177-178. Vernacchio L, Neufeld EJ, MacDonald K, et al. Combined schedule of 7-valent pneumococcal conjugate vaccine followed by 23-valent pneumococcal vaccine in children and young adults with sickle cell disease. J Pediatr. 1998;133:275278. Gaston MH, Verter JI, Woods G, et al. Prophylaxis with oral penicillin in children with sickle cell anemia. A randomized trial. N Engl J Med. 1986;314:1593-1599.
Copyright © 2014 Lippincott Williams & Wilkins. Unauthorized reproduction of this article is prohibited.
Context: Sickle cell disease (SCD) confers an increased risk of invasive pneumococcal disease, especially among young children. Pneumococcal vaccination decreases this risk, but the completion rate of age-appropriate vaccinations is not well defined in SCD. Objective: The goal of this study was to assess whether pneumococcal vaccines are administered to high-risk children with SCD according to recommended vaccine schedules. Design: A case-control design was used to conduct this study. Setting: Administrative data were obtained on Michigan Medicaid or Children’s Special Health Care Services programs enrollees. In addition, Michigan Newborn Screening and Michigan Care Improvement Registry records were used to confirm diagnosis and vaccine administration. Participants: This study compared pneumococcal vaccination rates in a cohort of 179 children with SCD with 537 age-matched non-SCD controls (1:3) enrolled in the Michigan Medicaid Program between 2001 and 2008. Study subjects were born in the state of Michigan between 2001 and 2005. Main Outcome Measure: The main outcome measure was the proportion of children defined as up to date for pneumococcal vaccines at defined milestone ages. Results: Children with SCD had significantly higher vaccination rates than controls, yet these values were much lower than state and national immunization survey rates. Conclusion: Barriers to completing age-appropriate recommended pneumococcal immunizations should be identified and addressed to further reduce invasive pneumococcal disease in this high-risk patient population. KEY WORDS: invasive pneumococcal disease, pneumococcal
vaccine, sickle cell disease
Sickle cell disease (SCD) affects nearly 100 000 persons in the United States and millions worldwide.1 Functional asplenia in infancy2 renders these children highly susceptible to invasive Streptococcus pneumoniae infection, particularly between the ages of 1 and 3 years.3,4 The risk of invasive pneumococcal disease (IPD) in SCD is estimated at 300 times the general population5 and overall death rate 100 times higher than normal.6 Invasive pneumococcal disease is determined when the bacteria are isolated from a sterile site (such as the blood or cerebrospinal fluid) or suspected invasive infection is documented in the medical record or on a death certificate.7 Accordingly, patients with SCD are identified as at high risk for IPD by the World Health Organization,8 the American Academy of Pediatrics,9 and the Centers for Disease Control and Prevention.10 Recent studies document that targeted and universal pneumococcal vaccination (PV) decreases IPD among children with SCD.5,6,11 The American Academy of Pediatrics Committee on Infectious Diseases outlines specific vaccine recommendations for these highrisk patients to include the complete pneumococcal protein–conjugate and polysaccharide vaccine series.12 Few data exist, however, regarding the degree to which children with SCD actually receive these recommended vaccinations in an age-appropriate manner. Author Affiliations: Departments of Internal Medicine and Pediatrics, Division of Hematology-Oncology, UT Southwestern Medical Center, Dallas, Texas (Dr Nero), Maryland Inpatient Care Specialist, Glen Burnie, Maryland (Dr Akuete); Department of Epidemiology, University of Michigan School of Public Health, Ann Arbor (Ms Reeves); and Department of Pediatrics, University of Michigan, Ann Arbor (Dr Dombkowski). The authors thank Drs George Buchanan and Timothy McCavit for encouragement and critical reading of the manuscript. They also thank Shiming Dong for statistical support, Sarah J. Clark, MPH, for contributions during the planning of this study, and the Michigan Department of Community Health for assistance with obtaining newborn screening data. None of the authors declare conflict of interest or source funding.
J Public Health Management Practice, 2014, 20(6), 587–590 C 2014 Wolters Kluwer Health | Lippincott Williams & Wilkins Copyright
Correspondence: Alecia C. Nero, MD, Departments of Internal Medicine and Pediatrics, Division of Hematology-Oncology, UT Southwestern Medical Center, 5323 Harry Hines Blvd, Dallas, TX 75390 ([email protected]). DOI: 10.1097/PHH.0000000000000034
587 Copyright © 2014 Lippincott Williams & Wilkins. Unauthorized reproduction of this article is prohibited.
588 ❘ Journal of Public Health Management and Practice The objective of this study was to assess whether children with SCD receive PV age-appropriately, comparing the completeness and timeliness of these vaccinations with their non-SCD counterparts.
● Methods This study assessed PV rates and timing, including both PCV7 (pneumococcal conjugate vaccine, Prevnar7) and PPV23 (pneumococcal polysaccharide vaccine, Pneumovax), in children with SCD using a case-control study design. This study was approved by the University of Michigan institutional review board.
Study population All SCD cases were enrolled in Michigan Medicaid or Children’s Special Health Care Services (CSHCS) programs between 2001 and 2008. They were born in Michigan during 2001-2005, following introduction of PCV7 into the US immunization schedule. For each case, 3 controls using a random sample of Medicaid beneficiaries were matched by birth month/year, race, and county. Medicaid eligibility and demographic characteristics were obtained for all children until 59 months of age from Medicaid administrative files.
SCD case classification The cases of SCD were classified as those having more than 3 SCD claims for inpatient, outpatient, or emergency department services or having SCD as a qualifying diagnosis for participation in CSHCS programs. It was defined to include sickle β-thalassemia, sickle cell anemia, sickle hemoglobin-C, and unspecified SCD represented by the following International Classification of Diseases, Ninth Revision, codes: (282.41, 282.42, 282.6, 282.60, 282.61, 282.62, 282.63, and 282.64). All other hemoglobinopathies were excluded. Cases meeting these criteria were subsequently verified through Michigan Newborn Screening records.
Outcomes measured The primary outcome assessed was the proportion of children up to date for PV at key milestone ages defined as at least 1 vaccine dose by 3 months, 2 doses by 5 months, and 3 doses by 7 months of age. Receipt of PV was identified in claims data using Current Procedural Terminology codes (PCV7: 90669; PPV23: 90732). Doses for “Streptococcus pneumoniae (pneumococcus)” without PCV7 or PPV23 designation were included using International Classification of Diseases, Ninth Revision, Clinical Modification, diagnosis codes (V0382, V066).
Vaccination records were obtained for cases and controls from the Michigan Care Improvement Registry, a population-based registry that automatically initiates a new record for children born in Michigan using inputs from electronic birth certificates. Michigan law requires that providers report all vaccinations administered to children into the Michigan Care Improvement Registry. Proportions were compared by the Fisher exact test for significance.
● Results A total of 235 children with SCD were identified and 179 (76%) were confirmed through newborn screening validation. Next, 537 controls (3:1) were matched to confirmed cases. By 3 months of age, 129 children with SCD (72%) and 322 without SCD (60%) were up to date with PV (Figure). By 5 months of age, 54% and 42% of children, respectively, were up to date, and by 7 months of age, 40% of cases and 24% of controls received at least 3 doses. At all ages, children with SCD had significantly higher rates of PV than controls (P < 0.01). Extending the age cutoff showed similar results, that is, the proportion of children receiving at least 3 doses increased substantially, reaching 73% with SCD and 54% without SCD by 24 months of age. Again, at least 4 doses were documented in 73% of children with SCD and 35% of children without SCD by 59 months of age. These data reflect significantly higher PV rates in children with SCD than in controls (Figure; P < .0001).
● Discussion Despite well-known risk of life-threatening IPD among children with SCD and documented decreased infection rates since availability of licensed vaccines, adherence to published recommendations remains poorly defined. Studies have evaluated IPD rates in SCD during the pneumococcal vaccine era but are often assessed after cases of IPD were identified.13,14 Documentation of age-appropriate PV in SCD helps assess the continued extent of undervaccination among this high-risk group. This cohort of high-risk children with SCD had higher PV rates than controls but were lower than the 2008 National Immunization Survey (NIS) data.15 The reported PV average rates for the state of Michigan and nationwide were nearly identical to each other at every age cutoff for that year. However, rates in the SCD cohort were lower at 3 months (72% vs 84%), 5 months (54% vs 74%), and 24 months (73% vs 92%) than these state/national rates. This suggests barriers to timely PV in our study population, prompting the need to
Copyright © 2014 Lippincott Williams & Wilkins. Unauthorized reproduction of this article is prohibited.
Pneumococcal Vaccination Rates in Children With Sickle Cell Disease
❘ 589
FIGURE ● PVa status, Children Younger Than 59 Months Born 2001-2005b
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Abbreviations: PV, pneumococcal vaccination; SCD, sickle cell disease; UTD, up to date (defined as the appropriate number of pneumococcal vaccines received by age reported in months). a PV includes PCV7 and/or PPSV23. b All group comparisons were statistically significant, P < .01.
better target obstacles that hinder age-appropriate immunizations in high-risk children with SCD. Caution should be taken when comparing data in this cohort with NIS data, since there were 2 periods of PCV7 vaccine shortages between 2001 and 2008, and official recommendations asked providers to withhold the third and fourth doses of PCV7 to healthy but not high-risk patients.16,17 This recommendation should favor vaccinations in children with SCD, therefore making the difference between the study population and NIS data even more concerning. There are several limitations of this study. First, the analysis included only children in the Michigan Medicaid or CSHCS databases, so generalizations to children with SCD nationally may not be appropriate. However, this sample is representative of the state, as approximately 75% of SCD cases are in the data warehouses that include Medicaid, CSHCS, or both. Second, the control group was well matched by demographics but may have included other high-risk individuals without SCD. Third, the clinical consequences of incomplete immunization status is unclear since patients with SCD can generate immunologic response even after 1 vaccine dose, similar to that of infants without disease.18 Therefore, incomplete PV may still provide some protection against IPD. Routine prophylactic antibiotic use, as well as herd immunity, may also contribute to lower risk of IPD in children with SCD.19 Fourth, our data do not distinguish immunization rates between PCV7 and PPV23 because of coding ambiguities. This may confound the results since PPV23 is not included in the primary series but recommended for high-risk children such as those with SCD after 2 years of age.12 The observed increased PV rates among older children may, therefore, reflect
PPV23 use rather than late administration of PCV7. In addition, national and state averages may be variable from year to year, which was not documented here. In conclusion, these data indicate that PV completion rates are lower than NIS survey state and national rates. Therefore, children with SCD may be at increased risk for fatal IPD. With better definition of barriers to age-appropriate PV rates in SCD, interventions can be offered to address these issues. Such strategies can include targeted provider and patient education to improve community outreach or provider use of state registries to help identify high-risk children. Other efforts may work to ensure adequate vaccine supply to areas lacking resources or engaging local and state agencies to implement regional-specific immunization programs.
REFERENCES 1. Hassell KL. Population estimates of sickle cell disease in the U.S. Am J Prev Med. 2010;38(4S):S512-S521. 2. Serjeant GR, Serjeant BE. Sickle Cell Disease. 3rd ed. New York, NY: Oxford University Press; 2001. 3. Wong WY, Overturf GD, Powars DR. Infection caused by Streptococcus pneumonia in children with sickle cell disease: epidemiology, immunologic mechanisms, prophylaxis, and vaccination. Clin Infect Dis. 1992;14(5):1124-1136. 4. Leikin SL, Gallagher D, Kinney TR, et al. Mortality in children and adolescents with sickle cell disease. Cooperative study of sickle cell disease. Pediatrics. 1989;84(3):500-508. 5. Adamkiewicz TV, Sarnaik S, Buchanan GR, et al. Invasive pneumococcal infections in children with sickle cell disease in the era of penicillin prophylaxis, antibiotic resistance, and 23valent pneumococcal polysaccharide vaccination. J Pediatr. 2003;143:438-444.
Copyright © 2014 Lippincott Williams & Wilkins. Unauthorized reproduction of this article is prohibited.
590 ❘ Journal of Public Health Management and Practice 6. McCavit TL, Xuan L, Zhang S, et al. Hospitalization for invasive pneumococcal disease in a national sample of children with sickle cell disease before and after PCV7 licensure. Pediatr Blood Cancer. 2012;58:945-949. 7. Centers for Disease Control and Prevention. Manual for the Surveillance of Vaccine-Preventable Diseases, 5th ed. Atlanta, GA: Centers for Disease Control and Prevention; 2008:chap 11. 8. World Health Organization. Pneumococcal vaccines: World Health Organization position paper. WHO Wkly Epidemiol Rec. 1999;74(23)150-151. 9. American Academy of Pediatrics. Red Book: 2009 Report of the Committee on Infectious Diseases. 28th ed. Chicago, IL: American Academy of Pediatrics; 2009. 10. Centers for Disease Control and Prevention. Epidemiology and Prevention of Vaccine-Preventable Diseases. 12th ed. Washington, DC: Public Health Foundation; 2011. 11. Ellison AM, Ota KV, McGowan KL, et al. Pneumococcal bacteremia in a vaccinated pediatric sickle cell disease population. Pediatr Infect Dis J. 2012;31:534-536. 12. American Academy of Pediatrics Committee on Infectious Diseases. Recommendations for the prevention of Streptococcus pneumoniae in infants and children: use of 13-valent pneumococcal conjugate vaccine (PCV13) and pneumococcal polysaccharide vaccine (PPSV23). Pediatrics. 2010;126(1): 186-190. 13. Halasa NB, Shankar SM, Talbot TR, et al. Incidence of invasive pneumococcal disease among individuals with
14.
15.
16.
17.
18.
19.
sickle cell disease before and after the introduction of the pneumococcal conjugate vaccine. Clin Infect Dis. 2007;44: 1428-1433. McCavit TL, Quinn CT, Techasaensiri C, Rogers ZR. Increase in invasive Streptococcus pneumonia infections in children with sickle cell disease since pneumococcal conjugate vaccine licensure. J Pediatr. 2011;158:505-507. Centers for Disease Control and Prevention. National Immunization Survey Tables. http://www.cdc.gov/vaccines/ stats-surv/nis/data/tables 2008.htm. Accessed February 4, 2011. Santoli JM, Peter G, Arvin AM, et al. Strengthening the supply of routinely recommended vaccines in the United States: recommendations from the National Vaccine Advisory Committee. JAMA. 2003;290(23):31223128. Centers for Disease Control and Prevention. Updated recommendations on the use of pneumococcal conjugate vaccine: suspension of recommendation for third and fourth dose. MMWR Morb Mortal Wkly Rep. 2004;53(8):177-178. Vernacchio L, Neufeld EJ, MacDonald K, et al. Combined schedule of 7-valent pneumococcal conjugate vaccine followed by 23-valent pneumococcal vaccine in children and young adults with sickle cell disease. J Pediatr. 1998;133:275278. Gaston MH, Verter JI, Woods G, et al. Prophylaxis with oral penicillin in children with sickle cell anemia. A randomized trial. N Engl J Med. 1986;314:1593-1599.
Copyright © 2014 Lippincott Williams & Wilkins. Unauthorized reproduction of this article is prohibited.
