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1.  Vaccination Coverage Among U.S. Adolescents Aged 13–17 Years Eligible for the Vaccines for Children Program, 2009 
Public Health Reports  2011;126(Suppl 2):124-134.
We compared (1) characteristics of adolescents who are and are not entitled to receive free vaccines from the Vaccines for Children (VFC) program and (2) vaccination coverage with meningococcal conjugate (MCV4), quadrivalent human papillomavirus (HPV4), and tetanus-diphtheria-acellular pertussis (Tdap) vaccines among VFC-eligible and non-VFC-eligible adolescents.
We analyzed data from the 2009 National Immunization Survey-Teen, a nationally representative, random-digit-dialed survey of households with adolescents aged 13–17 years (n=20,066). Differences in sociodemographic characteristics and provider-reported vaccination coverage were evaluated using t-tests.
Overall, 32.1% (±1.2%) of adolescents were VFC-eligible. VFC-eligible adolescents were significantly less likely than non-VFC-eligible adolescents to be white and to live in suburban areas, and more likely to live in poverty and to have younger and less educated mothers. Nationally, coverage among non-VFC-eligible adolescents was 57.1% (±1.5%) for ≥1 dose of Tdap, 55.4% (±1.5%) for ≥1 dose of MCV4, and 43.2% (±2.2%) for ≥1 dose of HPV4. Coverage among VFC-eligible adolescents was 52.5% (±2.4%) for ≥1 dose of Tdap, 50.1% (±2.4%) for ≥1 dose of MCV4, and 46.6% (±3.5%) for ≥1 dose of HPV4. Only 27.5% (±1.8%) of non-VFC-eligible adolescents and 25.0% (±2.9%) of VFC-eligible adolescents received ≥3 doses of HPV4. Vaccination coverage was significantly higher among non-VFC-eligible adolescents for Tdap and MCV4, but not for one-dose or three-dose HPV4.
Coverage with some recommended vaccines is lower among VFC-eligible adolescents compared with non-VFC-eligible adolescents. Continued monitoring of adolescent vaccination rates, particularly among VFC-eligible populations, is needed to ensure that all adolescents receive all routinely recommended vaccines.
PMCID: PMC3113437  PMID: 21815303
2.  Validity of Parent-Reported Vaccination Status for Adolescents Aged 13–17 Years: National Immunization Survey-Teen, 2008 
Public Health Reports  2011;126(Suppl 2):60-69.
The validity of parent-reported adolescent vaccination histories has not been assessed. This study evaluated the validity of parent-reported adolescent vaccination histories by a combination of immunization card and recall, and by recall only, compared with medical provider records.
We analyzed data from the 2008 National Immunization Survey-Teen. Parents of adolescents aged 13–17 years reported their child's vaccination history either by immunization card and recall (n=3,661) or by recall only (n=12,822) for the hepatitis B (Hep B), measles-mumps-rubella (MMR), varicella (VAR), tetanus-diphtheria/tetanus-diphtheria-acellular pertussis (Td/Tdap), meningococcal conjugate (MCV4), and quadrivalent human papillomavirus (HPV4) (for girls only) vaccines. We validated parental report with medical records.
Among the immunization card/recall group, vaccines with >20% false-positive reports included MMR (32.3%) and Td/Tdap (36.9%); vaccines with >20% false-negative reports included VAR (35.2%), MCV4 (36.0%), and Tdap (41.9%). Net bias ranged from −25.0 to −0.1 percentage points. Kappa values ranged from 0.22 to 0.92. Among the recall-only group, vaccines with >20% false-positive reports included Hep B (33.9%), MMR (61.4%), VAR (26.2%), and Td/Tdap (60.6%); vaccines with >20% false-negative reports included Hep B (58.9%), MMR (33.7%), VAR (51.6%), Td/Tdap (25.5%), Tdap (50.3%) MCV4 (63.0%), and HPV4 (20.5%). Net bias ranged from −46.0 to 0.5 percentage points. Kappa values ranged from 0.03 to 0.76.
Validity of parent-reported vaccination histories varies by type of report and vaccine. For recently recommended vaccines, false-negative rates were substantial and higher than false-positive rates, resulting in net underreporting of vaccination rates by both the immunization card/recall and recall-only groups. Provider validation of parent-reported vaccinations is needed for valid surveillance of adolescent vaccination coverage.
PMCID: PMC3113431  PMID: 21812170
3.  Intervention effects from a social marketing campaign to promote HPV vaccination in preteen boys 
Vaccine  2014;32(33):4171-4178.
Adoption of human papillomavirus (HPV) vaccination in the US has been slow. In 2011, HPV vaccination of boys was recommended by CDC for routine use at ages 11–12. We conducted and evaluated a social marketing intervention with parents and providers to stimulate HPV vaccination among preteen boys.
We targeted parents and providers of 9–13 year old boys in a 13 county NC region. The 3-month intervention included distribution of HPV vaccination posters and brochures to all county health departments plus 194 enrolled providers; two radio PSAs; and an online CME training. A Cox proportional hazards model was fit using NC immunization registry data to examine whether vaccination rates in 9–13 year old boys increased during the intervention period in targeted counties compared to control counties (n=15) with similar demographics. To compare with other adolescent vaccines, similar models were fit for HPV vaccination in girls and meningococcal and Tdap vaccination of boys in the same age range. Moderating effects of age, race, and Vaccines for Children (VFC) eligibility on the intervention were considered.
The Cox model showed an intervention effect (β=0.29, HR=1.34, p=.0024), indicating that during the intervention the probability of vaccination increased by 34% in the intervention counties relative to the control counties. Comparisons with HPV vaccination in girls and Tdap and meningococcal vaccination in boys suggest a unique boost for HPV vaccination in boys during the intervention. Model covariates of age, race and VFC eligibility were all significantly associated with vaccination rates (p<.0001 for all). HPV vaccination rates were highest in the 11–12 year old boys. Overall, three of every four clinic visits for Tdap and meningococcal vaccines for preteen boys were missed opportunities to administer HPV vaccination simultaneously.
Social marketing techniques can encourage parents and health care providers to vaccinate preteen boys against HPV.
PMCID: PMC4080713  PMID: 24886960
HPV vaccine; social marketing; preteen boys; adolescent immunization
4.  The impact of electronic health record (EHR) interoperability on immunization information system (IIS) data quality 
Objectives: To evaluate the impact of electronic health record (EHR) interoperability on the quality of immunization data in the North Dakota Immunization Information System (NDIIS). Methods: NDIIS doses administered data was evaluated for completeness of the patient and dose-level core data elements for records that belong to interoperable and non-interoperable providers. Data was compared at three months prior to electronic health record (EHR) interoperability enhancement to data at three, six, nine and twelve months post-enhancement following the interoperability go live date. Doses administered per month and by age group, timeliness of vaccine entry and the number of duplicate clients added to the NDIIS was also compared, in addition to, immunization rates for children 19 – 35 months of age and adolescents 11 – 18 years of age. Results: Doses administered by both interoperable and non-interoperable providers remained fairly consistent from pre-enhancement through twelve months post-enhancement. Comparing immunization rates for infants and adolescents, interoperable providers had higher rates both pre- and post-enhancement than non-interoperable providers for all vaccines and vaccine series assessed. The overall percentage of doses entered into the NDIIS within one month of administration varied slightly between interoperable and non-interoperable providers; however, there were significant changes between the percentage of doses entered within one day and within one week with the percentage entered within one day increasing and within one week decreasing with interoperability. The number of duplicate client records created by interoperable providers increased from 94 duplicates pre-enhancement to 10,552 at twelve months post-enhancement, while the duplicates from non-interoperable providers only increased from 300 to 637 over the same period. Of the 40 core data elements in the NDIIS, there was some difference in completeness between the interoperable versus non-interoperable providers. Only middle name, sex, county, phone number, mother’s maiden name, vaccine manufacturer, lot number and expiration date were significantly (>=5%) different between the two provider groups. Conclusions: Interoperability with provider EHRs has had an impact on NDIIS data quality. Timeliness of data entry has improved and overall doses administered have remained fairly consistent, as have the immunization rates for the providers assessed. There are more technical and non-technical interventions that will need to be accomplished by NDIIS staff and vendor to help reduce the negative impact of duplicate record creation, as well as, data completeness.
PMCID: PMC5065519  PMID: 27752294
Immunization information systems; electronic health records; meaningful use; HL7; data quality
5.  Immunogenicity, Safety, and Antibody Persistence at 3, 5, and 10 Years Postvaccination in Adolescents Randomized to Booster Immunization with a Combined Tetanus, Diphtheria, 5-Component Acellular Pertussis, and Inactivated Poliomyelitis Vaccine Administered with a Hepatitis B Virus Vaccine Concurrently or 1 Month Apart 
An understanding of the antibody persistence elicited by a combined tetanus, diphtheria, 5-component acellular pertussis, and inactivated poliovirus vaccine (Tdap-IPV) after adolescent vaccination is important to optimize booster dosing intervals. Our objectives were to compare the safety and immunogenicity of Tdap-IPV coadministered with hepatitis B vaccine (HepB) and sequential administration and evaluate humoral immunity at 3, 5, and 10 years after Tdap-IPV vaccination in adolescents. This phase II randomized, controlled, and open-label study enrolled 280 11- to 14-year-old adolescents with up to 10 years postvaccination follow-up. Group 1 (n = 145) received Tdap-IPV, followed by a HepB dose 1 month later, and group 2 (n = 135) received both vaccines simultaneously. No consistent increases in solicited reactions or unsolicited adverse events occurred with coadministration. All vaccinees attained seroprotective antibody levels at ≥0.01 IU/ml for diphtheria and tetanus, at a ≥1:8 dilution for poliovirus (serotypes 1, 2, and 3), and ≥10 mIU/ml for hepatitis B at 1 month postvaccination. Clinically relevant immunologic interactions did not occur with coadministration. For pertussis, all participants achieved seropositivity levels (at or above the lower limit of quantitation), and 72.7% to 95.8% had 4-fold increases in pertussis antibodies at 1 month postvaccination. At 10 years postvaccination, the remaining participants (62.8% of the original cohort) maintained seroprotective levels of ≥0.01 IU/ml for diphtheria and tetanus, a ≥1:8 dilution for all 3 poliovirus serotypes, and 74.1% to 98.2% maintained pertussis seropositivity levels depending on the antigen tested. There were no differences between the groups. These results support the coadministration of Tdap-IPV and HepB to adolescents and suggest that vaccination with Tdap-IPV can offer protection for 10 years after an adolescent booster vaccination.
PMCID: PMC4340898  PMID: 25540274
6.  Increasing Provision of Adolescent Vaccines in Primary Care: A Randomized Controlled Trial 
Pediatrics  2014;134(2):e346-e353.
To assess the effectiveness of in-person and webinar-delivered AFIX (Assessment, Feedback, Incentives, and eXchange) consultations for increasing adolescent vaccine coverage.
We randomly assigned 91 primary care clinics in North Carolina, serving 107 443 adolescents, to receive no consultation or an in-person or webinar AFIX consultation. We delivered in-person consultations in April through May 2011 and webinar consultations in May through August 2011. The state's immunization registry provided vaccine coverage data for younger patients (ages 11–12 years) and older patients (ages 13–18 years) for 3 adolescent vaccines: tetanus toxoid, reduced diphtheria toxoid, and acellular pertussis (Tdap); meningococcal; and human papillomavirus (HPV) vaccines (≥1 dose, females only).
At the 5-month follow-up, AFIX consultations increased vaccine coverage among younger adolescents. Patients in the in-person arm experienced coverage changes that exceeded those in the control arm for Tdap (3.4% [95% confidence interval (CI): 2.2 to 4.6]), meningococcal (4.7% [95% CI: 2.3 to 7.2], and HPV (1.5% [95% CI: 0.3 to 2.7]) vaccines. Patients in the webinar versus control arm also experienced larger changes for these vaccines. AFIX did little to improve coverage among older adolescents. At 1 year, the 3 arms showed similar coverage changes. The effectiveness of in-person and webinar consultations was not statistically different at either time point (all, P >.05).
Webinar AFIX consultations were as effective as in-person consultations in achieving short-term increases in vaccine coverage for younger adolescents. AFIX consultations for adolescents need improvement to have a stronger and more durable impact, especially for HPV vaccine.
PMCID: PMC4531274  PMID: 25002671
adolescent health services; human papillomavirus infections/prevention and control; North Carolina; vaccination/statistics and numerical data
7.  Tennessee’s 3-Star Report: Using Available Data Systems to Reduce Missed Opportunities to Vaccinate Preteens 
Biomedical Informatics Insights  2016;8(Suppl 2):15-21.
All preteens should receive tetanus–diphtheria–pertussis vaccine (Tdap), quadrivalent meningococcal vaccine (Men-ACWY), and the human papillomavirus (HPV) cancer vaccine series. In Tennessee, HPV vaccination rates have stagnated at low levels for a decade. Three fundamental strategies to reduce missed opportunities for immunization include administering all recommended vaccines at the same visit, making strong recommendations for vaccines, and auditing and feedback. In Tennessee, during each summer, a surge of preteens visit local health departments (LHDs) to receive a required Tdap vaccine before entering seventh grade, presenting an opportunity to administer Men-ACWY and HPV. The Tennessee Immunization Program (TIP) coined the term “3-Star visit” for such encounters and developed a monthly report to track them using data from the Patient Tracking Billing Management Information System (PTBMIS) used by LHDs across Tennessee. Implementation of this quality improvement report has correlated with a substantial increase in 3-Star visits from 2013 to 2016, particularly during the summer months.
PMCID: PMC5138065  PMID: 27980415
adolescent immunization; HPV vaccine; public health; information systems; quality improvement
8.  HPV vaccine decision making in pediatric primary care: a semi-structured interview study 
BMC Pediatrics  2011;11:74.
Despite national recommendations, as of 2009 human papillomavirus (HPV) vaccination rates were low with < 30% of adolescent girls fully vaccinated. Research on barriers to vaccination has focused separately on parents, adolescents, or clinicians and not on the decision making process among all participants at the point of care. By incorporating three distinct perspectives, we sought to generate hypotheses to inform interventions to increase vaccine receipt.
Between March and June, 2010, we conducted qualitative interviews with 20 adolescent-mother-clinician triads (60 individual interviews) directly after a preventive visit with the initial HPV vaccine due. Interviews followed a guide based on published HPV literature, involved 9 practices, and continued until saturation of the primary themes was achieved. Purposive sampling balanced adolescent ages and practice type (urban resident teaching versus non-teaching). Using a modified grounded theory approach, we analyzed data with NVivo8 software both within and across triads to generate primary themes.
The study population was comprised of 20 mothers (12 Black, 9 < high school diploma), 20 adolescents (ten 11-12 years old), and 20 clinicians (16 female). Nine adolescents received the HPV vaccine at the visit, eight of whom were African American. Among the 11 not vaccinated, all either concurrently received or were already up-to-date on Tdap and MCV4. We did not observe systematic patterns of vaccine acceptance or refusal based on adolescent age or years of clinician experience. We identified 3 themes: (1) Parents delayed, rather than refused vaccination, and when they expressed reluctance, clinicians were hesitant to engage them in discussion. (2) Clinicians used one of two strategies to present the HPV vaccine, either presenting it as a routine vaccine with no additional information or presenting it as optional and highlighting risks and benefits. (3) Teens considered themselves passive participants in decision making, even when parents and clinicians reported including them in the process.
Programs to improve HPV vaccine delivery in primary care should focus on promoting effective parent-clinician communication. Research is needed to evaluate strategies to help clinicians engage reluctant parents and passive teens in discussion and measure the impact of distinct clinician decision making approaches on HPV vaccine delivery.
PMCID: PMC3175168  PMID: 21878128
9.  Protecting Newborns by Immunizing Family Members in a Hospital-Based Vaccine Clinic: A Successful Tdap Cocooning Program During the 2010 California Pertussis Epidemic 
Public Health Reports  2014;129(3):245-251.
Infants are at greatest risk for mortality from pertussis infection. Since 2005, the Advisory Committee on Immunization Practices has recommended a cocooning strategy of vaccinating all close contacts of infants with tetanus, diptheria, and acellular pertussis (Tdap) vaccine to reduce the risk of transmitting pertussis. Difficulties in establishing a complete cocoon have been reported in the literature. We determined whether families of newborns could be fully immunized against pertussis, thereby providing a complete cocoon of protection.
Tdap vaccine was offered during visiting hours to contacts aged 7 years and older and to postpartum patients who had not received Tdap vaccine during pregnancy. We then conducted retrospective phone interviews with randomly selected mothers (or other family members) to assess vaccination rates. We compared household vaccination rates during intervention and control periods and the demographic factors associated with Tdap vaccination of all members within the households.
During the intervention period, 243 postpartum patients and 1,287 other family members of newborns were immunized, with 84.8% of all family members receiving Tdap vaccination. Seventy-six percent of households reported a complete cocoon. In the control group, 52.2% of all family members received Tdap vaccination, and 29.3% of households had a complete cocoon. In the control group, fewer family members completed Tdap vaccination in the larger households than in the smaller households (p=0.008).
A cocooning strategy can be successfully implemented, such that the majority of newborns leave the hospital with their families fully immunized against pertussis.
PMCID: PMC3982543  PMID: 24791022
10.  Safety and Immunogenicity of Tetanus Diphtheria and Acellular Pertussis (Tdap) Immunization During Pregnancy in Mothers and Infants: A Randomized Clinical Trial 
JAMA  2014;311(17):1760-1769.
Maternal immunization with tetanus toxoid and reduced diphtheria toxoid acellular pertussis (Tdap) vaccine could prevent infant pertussis. The effect of vaccine-induced maternal antibodies on infant responses to diphtheria and tetanus toxoids acellular pertussis (DTaP) immunization is unknown.
To evaluate the safety and immunogenicity of Tdap immunization during pregnancy and its effect on infant responses to DTaP.
Design, Setting and Participants
Phase I, randomized, double-masked, placebo-controlled clinical trial conducted in private (Houston) and academic (Durham, Seattle) obstetric practices from 2008 to 2012. Forty eight healthy 18–45 year-old pregnant women received Tdap (n=33) or placebo (n=15) at 30–32 weeks’ gestation with cross-over Tdap immunization postpartum.
Tdap vaccination at 30–32 weeks’ gestation or post-partum.
Outcome Measures
Primary: Maternal and infant adverse events, pertussis illness and infant growth and development (Bayley-III screening test) until 13 months of age. Secondary: Antibody concentrations in pregnant women before and 4 weeks after Tdap immunization or placebo, at delivery and 2 months postpartum, and in infants at birth, 2 months, and after the third (7 months) and fourth (13 months) doses of DTaP.
All participants delivered healthy newborns. No Tdap-associated serious adverse events occurred in women or infants. Injection site reactions after Tdap immunization were reported in 78.8% (95% CI: 61.1%, 91.0%) and 80% (CI: 51.9%, 95.7%) pregnant and postpartum women, respectively. Injection site pain was the predominant symptom. Systemic symptoms were reported in 36.4% (CI: 20.4%, 54.9%) and 73.3% (CI: 44.9%, 92.2%) pregnant and postpartum women, respectively. Malaise and myalgia were most common. Growth and development were similar in both infant groups. No cases of pertussis occurred. Significantly higher concentrations of pertussis antibodies were measured at delivery in women who received Tdap during pregnancy and in their infants at birth and at age 2 months when compared to infants of women immunized postpartum. Antibody responses in infants of Tdap recipients during pregnancy were modestly lower after 3 DTaP doses, but not different following the fourth dose.
Conclusions and Relevance
This preliminary safety assessment did not find an increased risk of adverse events among women who received Tdap vaccine at 30–32 weeks’ gestation or their infants. Maternal immunization with Tdap resulted in high concentrations of pertussis antibodies in infants during the first 2 months of life and did not substantially alter infant responses to DTaP. Further research is needed to provide definitive evidence of the safety and efficacy of Tdap vaccination during pregnancy.
Trial Registration, study identifier: NCT00707148. URL:
PMCID: PMC4333147  PMID: 24794369
Maternal immunization; Pertussis; infants; maternal antibodies; response to active immunization
11.  Physician communication about adolescent vaccination: How is human papillomavirus vaccine different? 
Preventive medicine  2015;77:181-185.
Low human papillomavirus (HPV) vaccination coverage stands in stark contrast to our success in delivering other adolescent vaccines. To identify opportunities for improving physicians’ recommendations for HPV vaccination, we sought to understand how the communication context surrounding adolescent vaccination varies by vaccine type.
A national sample of 776 U.S. physicians (53% pediatricians, 47% family medicine physicians) completed our online survey in 2014. We assessed physicians’ perceptions and communication practices related to recommending adolescent vaccines for 11- and 12-year-old patients.
About three-quarters of physicians (73%) reported recommending HPV vaccine as highly important for patients, ages 11–12. More physicians strongly recommended tetanus, diphtheria, and acellular pertussis (Tdap) (95%) and meningococcal vaccines (87%, both p<0.001) for this age group. Only 13% of physicians perceived HPV vaccine as being highly important to parents, which was far fewer than perceived parental support for Tdap (74%) and meningococcal vaccines (62%, both p<0.001). Physicians reported that discussing HPV vaccine took almost twice as long as discussing Tdap. Among physicians with a preferred order for discussing adolescent vaccines, most (70%) discussed HPV vaccine last.
Our findings suggest that primary care physicians perceived HPV vaccine discussions to be burdensome, requiring more time and engendering less parental support than other adolescent vaccines. Perhaps for this reason, physicians in our national study recommended HPV vaccine less strongly than other adolescent vaccines, and often chose to discuss it last. Communication strategies are needed to support physicians in recommending HPV vaccine with greater confidence and efficiency.
PMCID: PMC4490050  PMID: 26051197
adolescent health; human papillomavirus infections/prevention & control; health communication; quality of health care
12.  Impact of a physician recommendation and parental immunization attitudes on receipt or intention to receive adolescent vaccines 
Human Vaccines & Immunotherapeutics  2013;9(12):2627-2633.
Four vaccines are recommended by the Centers for Disease Control and Prevention’s Advisory Committee on Immunization Practices for adolescents. Parental attitudes may play a key role in vaccination uptake in this age group. In 2011, we conducted a cross-sectional survey among parents of adolescents in one county in Georgia to identify parental attitudes toward adolescent vaccination, reasons for vaccine acceptance or refusal, and impact of a physician recommendation for vaccination. Physician recommendation was reported as one of the top reasons for receipt or intent to receive any of the vaccines. Physician recommendation of any of the four vaccines was associated with receipt of Tdap (p < 0.001), MCV4 (p < 0.001), and HPV (p = 0.03) and intent to receive Tdap (p = 0.05), MCV4 (p = 0.005), and HPV (p = 0.05). Compared with parents who did not intend to have their adolescent vaccinated with any of the vaccines, parents who did intend reported higher perceived susceptibility (3.12 vs. 2.63, p = 0.03) and severity of disease (3.89 vs. 3.70, p = 0.02) and higher perceived benefit of vaccination (8.48 vs. 7.74, p = 0.02). These findings suggest that future vaccination efforts geared toward parents may benefit from addressing the advantages of vaccination and enhancing social norms. Physicians can play a key role by providing information on the benefits of adolescent vaccination.
PMCID: PMC4162064  PMID: 23883781
adolescent; vaccine; attitudes; health belief model, theory of reasoned action
13.  A Population-Based Evaluation of a Publicly Funded, School-Based HPV Vaccine Program in British Columbia, Canada: Parental Factors Associated with HPV Vaccine Receipt 
PLoS Medicine  2010;7(5):e1000270.
Analysis of a telephone survey by Gina Ogilvie and colleagues identifies the parental factors associated with HPV vaccine uptake in a school-based program in Canada.
Information on factors that influence parental decisions for actual human papillomavirus (HPV) vaccine receipt in publicly funded, school-based HPV vaccine programs for girls is limited. We report on the level of uptake of the first dose of the HPV vaccine, and determine parental factors associated with receipt of the HPV vaccine, in a publicly funded school-based HPV vaccine program in British Columbia, Canada.
Methods and Findings
All parents of girls enrolled in grade 6 during the academic year of September 2008–June 2009 in the province of British Columbia were eligible to participate. Eligible households identified through the provincial public health information system were randomly selected and those who consented completed a validated survey exploring factors associated with HPV vaccine uptake. Bivariate and multivariate analyses were conducted to calculate adjusted odds ratios to identify the factors that were associated with parents' decision to vaccinate their daughter(s) against HPV. 2,025 parents agreed to complete the survey, and 65.1% (95% confidence interval [CI] 63.1–67.1) of parents in the survey reported that their daughters received the first dose of the HPV vaccine. In the same school-based vaccine program, 88.4% (95% CI 87.1–89.7) consented to the hepatitis B vaccine, and 86.5% (95% CI 85.1–87.9) consented to the meningococcal C vaccine. The main reasons for having a daughter receive the HPV vaccine were the effectiveness of the vaccine (47.9%), advice from a physician (8.7%), and concerns about daughter's health (8.4%). The main reasons for not having a daughter receive the HPV vaccine were concerns about HPV vaccine safety (29.2%), preference to wait until the daughter is older (15.6%), and not enough information to make an informed decision (12.6%). In multivariate analysis, overall attitudes to vaccines, the impact of the HPV vaccine on sexual practices, and childhood vaccine history were predictive of parents having a daughter receive the HPV vaccine in a publicly funded school-based HPV vaccine program. By contrast, having a family with two parents, having three or more children, and having more education was associated with a decreased likelihood of having a daughter receive the HPV vaccine.
This study is, to our knowledge, one of the first population-based assessments of factors associated with HPV vaccine uptake in a publicly funded school-based program worldwide. Policy makers need to consider that even with the removal of financial and health care barriers, parents, who are key decision makers in the uptake of this vaccine, are still hesitant to have their daughters receive the HPV vaccine, and strategies to ensure optimal HPV vaccine uptake need to be employed.
Please see later in the article for the Editors' Summary
Editors' Summary
About 10% of cancers in women occur in the cervix, the structure that connects the womb to the vagina. Every year, globally, more than a quarter of a million women die because of cervical cancer, which only occurs after the cervix has been infected with a human papillomavirus (HPV) through sexual intercourse. There are many types of HPV, a virus that infects the skin and the mucosa (the moist membranes that line various parts of the body, including the cervix). Although most people become infected with HPV at some time in their life, most never know they are infected. However, some HPV types cause harmless warts on the skin or around the genital area and several—in particular, HPV 16 and HPV 18, so-called high-risk HPVs—can cause cervical cancer. HPV infections are usually cleared by the immune system, but about 10% of women infected with a high-risk HPV develop a long-term infection that puts them at risk of developing cervical cancer.
Why Was This Study Done?
Screening programs have greatly reduced cervical cancer deaths in developed countries in recent decades by detecting the cancer early when it can be treated; but it would be better to prevent cervical cancer ever developing. Because HPV is necessary for the development of cervical cancer, vaccination of girls against HPV infection before the onset of sexual activity might be one way to do this. Scientists recently developed a vaccine that prevents infection with HPV 16 and HPV 18 (and with two HPVs that cause genital warts) and that should, therefore, reduce the incidence of cervical cancer. Publicly funded HPV vaccination programs are now planned or underway in several countries; but before girls can receive the HPV vaccine, parental consent is usually needed, so it is important to know what influences parental decisions about HPV vaccination. In this study, the researchers undertake a telephone survey to determine the uptake of the HPV vaccine by 11-year-old girls (grade 6) in British Columbia, Canada, and to determine the parental factors associated with vaccine uptake; British Columbia started a voluntary school-based HPV vaccine program in September 2008.
What Did the Researchers Do and Find?
In early 2009, the researchers contacted randomly selected parents of girls enrolled in grade 6 during the 2008–2009 academic year and asked them to complete a telephone survey that explored factors associated with HPV vaccine uptake. 65.1% of the 2,025 parents who completed the survey had consented to their daughter receiving the first dose of HPV vaccine. By contrast, more than 85% of the parents had consented to hepatitis B and meningitis C vaccination of their daughters. Nearly half of the parents surveyed said their main reason for consenting to HPV vaccination was the effectiveness of the vaccine. Conversely, nearly a third of the parents said concern about the vaccine's safety was their main reason for not consenting to vaccination and one in eight said they had been given insufficient information to make an informed decision. In a statistical analysis of the survey data, the researchers found that a positive parental attitude towards vaccination, a parental belief that HPV vaccination had limited impact on sexual practices, and completed childhood vaccination increased the likelihood of a daughter receiving the HPV vaccine. Having a family with two parents or three or more children and having well-educated parents decreased the likelihood of a daughter receiving the vaccine.
What Do These Findings Mean?
These findings provide one of the first population-based assessments of the factors that affect HPV vaccine uptake in a setting where there are no financial or health care barriers to vaccination. By identifying the factors associated with parental reluctance to agree to HPV vaccination for their daughters, these findings should help public-health officials design strategies to ensure optimal HPV vaccine uptake, although further studies are needed to discover why, for example, parents with more education are less likely to agree to vaccination than parents with less education. Importantly, the findings of this study, which are likely to be generalizable to other high-income countries, indicate that there is a continued need to ensure that the public receives credible, clear information about both the benefits and long-term safety of HPV vaccination.
Additional Information
Please access these Web sites via the online version of this summary at
The US National Cancer Institute provides information about cervical cancer for patients and for health professionals, including information on HPV vaccines (in English and Spanish)
The US Centers for Disease Control and Prevention also has information about cervical cancer and about HPV
The UK National Health Service Choices website has pages on cervical cancer and on HPV vaccination
More information about cervical cancer and HPV vaccination is available from the Macmillan cancer charity
ImmunizeBC provides general information about vaccination and information about HPV vaccination in British Columbia
MedlinePlus provides links to additional resources about cervical cancer (in English and Spanish)
PMCID: PMC2864299  PMID: 20454567
14.  Uptake of meningococcal conjugate vaccine among adolescents in large managed care organizations, United States, 2005: Demand, supply and seasonality 
In February 2005, the US Advisory Committee on Immunization Practices recommended the new meningococcal conjugate vaccine (MCV4) for routine use among 11- to 12-year-olds (at the preadolescent health-care visit), 14- to 15-year-olds (before high-school entry), and groups at increased risk. Vaccine distribution started in March; however, in July, the manufacturer reported inability to meet demand and widespread MCV4 shortages were reported. Our objectives were to determine early uptake patterns among target (11-12 and 14-15 year olds) and non-target (13- plus 16-year-olds) age groups. A post hoc analysis was conducted to compare seasonal uptake patterns of MCV4 with polysaccharide meningococcal (MPSV4) and tetanus diphtheria (Td) vaccines.
We analyzed data for adolescents 11-16 years from five managed care organizations participating in the Vaccine Safety Datalink (VSD). For MCV4, we estimated monthly and cumulative coverage during 2005 and calculated risk ratios. For MPSV4 and Td, we combined 2003 and 2004 data and compared their seasonal uptake patterns with MCV4.
Coverage for MCV4 during 2005 among the 623,889 11-16 years olds was 10%. Coverage for 11-12 and 14-15 year olds was 12% and 11%, respectively, compared with 8% for 13- plus 16-year-olds (p < 0.001). Of the 64,272 MCV4 doses administered from March-December 2005, 73% were administered June-August. Fifty-nine percent of all MPSV4 doses and 38% of all Td doses were administered during June-August.
A surge in vaccine uptake between June and August was observed among adolescents for MCV4, MPSV4 and Td vaccines. The increase in summer-time vaccinations and vaccination of non-targeted adolescents coupled with supply limitations likely contributed to the reported shortages of MCV4 in 2005.
PMCID: PMC2781813  PMID: 19887009
15.  Randomized Trial on the Safety, Tolerability, and Immunogenicity of MenACWY-CRM, an Investigational Quadrivalent Meningococcal Glycoconjugate Vaccine, Administered Concomitantly with a Combined Tetanus, Reduced Diphtheria, and Acellular Pertussis Vaccine in Adolescents and Young Adults▿ †  
This study evaluated the safety, tolerability, and immunogenicity of an investigational quadrivalent meningococcal conjugate vaccine, MenACWY-CRM, when administered concomitantly with a combined tetanus, reduced diphtheria, and acellular pertussis (Tdap) vaccine, in subjects aged 11 to 25 years. Subjects received either MenACWY-CRM and Tdap, MenACWY-CRM and saline placebo, or Tdap and saline placebo. No significant increase in reactogenicity and no clinically significant vaccine-related adverse events (AEs) occurred when MenACWY-CRM and Tdap were administered concomitantly. Similar immunogenic responses to diphtheria, tetanus, and meningococcal (serogroups A, C, W-135, and Y) antigens were observed, regardless of concomitant vaccine administration. Antipertussis antibody responses were comparable between vaccine groups for filamentous hemagglutinin and were slightly lower, although not clinically significantly, for pertussis toxoid and pertactin when the two vaccines were administered concomitantly. These results indicate that the investigational MenACWY-CRM vaccine is well tolerated and immunogenic and that it can be coadministered with Tdap to adolescents and young adults.
PMCID: PMC2849330  PMID: 20164251
16.  Preliminary study on the immunogenicity of a newly developed GCC Tdap vaccine and its protection efficacy against Bordetella pertussis in a murine intranasal challenge model 
Active reduced dose tetanus-diphtheria-acellular pertussis (Tdap) vaccination for adolescents and adults is necessary because waning immunity after primary diphtheria-tetanus-pertussis vaccination is related to the recent emergence of pertussis. This study was conducted to compare the immunogenicity and protection efficacy against Bordetella pertussis between a new GCC Tdap vaccine and a commercially available Tdap vaccine in a murine model.
Materials and Methods
BALB/c mice were immunized with two doses of diphtheria-tetanus-acellular pertussis (DTaP) vaccine for priming and a subsequent Tdap booster vaccination. According to the type of booster vaccine, mice were divided into four groups: commercially available Tdap vaccine in group 1 and GCC Tdap vaccines of different combinations of pertussis antigens in groups 2 to 4. Humoral and cell-mediated immune responses and protection efficacy using a murine intranasal challenge model after booster vaccination were compared among the four groups.
Every group showed significant increases in antibody titers against pertussis antigens such as pertussis toxin, filamentous hemagglutinin, and pertactin after booster vaccination. Spleen cells showed both Th1 and Th2 cell-mediated immune responses stimulated by pertussis antigens in all groups without any significant difference. In the intranasal B. pertussis infection model, bacteria were eradicated in all groups five days after challenge infection.
This preliminary study did not show significantly different immunogenicity or protection efficacy of the new GCC Tdap vaccines compared to the commercially available Tdap vaccine, although a more extensive study is necessary to assess the differing efficacies of the new GCC Tdap vaccines.
PMCID: PMC4313112  PMID: 25649262
Diphtheria-tetanus-acellular pertussis vaccine; Immunogenicity; Efficacy; Mice; Republic of Korea
17.  Health care professionals and adolescent vaccination 
Human Vaccines & Immunotherapeutics  2014;10(9):2629-2630.
In their recently published research study, Gargano et al. found that a physician's recommendation and parental health beliefs had significant effects on adolescent vaccination rates and on parental intentions to vaccinate. This research replicates the findings of a number of human papillomavirus (HPV) vaccine-focused research studies, but explores new territory by focusing on all recommended adolescent vaccines: meningococcal-conjugate (MCV4), HPV, influenza, and tetanus, diphtheria, and acellular pertussis (Tdap) vaccines. Although Gargano et al.'s study is relatively small in scale and focuses on only one county in Georgia, their results are consistent with many other research reports, suggesting that their findings are robust and replicable. Most published intervention studies have targeted parents and young adults, with little focus on health care professionals. However, given the centrality of physician recommendation in adolescent vaccination, as shown by Gargano et al., it is clear that the time has come to develop and evaluate interventions that help physicians and other health care professionals to more effectively implement strong and routine recommendations for all adolescent platform vaccines.
PMCID: PMC4975052  PMID: 25483506
adolescent; vaccine; attitude to health; intervention studies; delivery of health care
18.  Human papillomavirus vaccination among adolescents in Georgia 
Human Vaccines & Immunotherapeutics  2015;11(7):1703-1708.
Human papillomavirus (HPV) vaccination coverage for adolescent females and males remains low in the United States. We conducted a 3-arm randomized controlled trial (RCT) conducted in middle and high schools in eastern Georgia from 2011–2013 to determine the effect of 2 educational interventions used to increase adolescent vaccination coverage for the 4 recommended adolescent vaccines: Tdap, MCV4, HPV and influenza. As part of this RCT, this article focuses on: 1) describing initiation and completion of HPV vaccine series among a diverse population of male and female adolescents; 2) assessing parental attitudes toward HPV vaccine; and 3) examining correlates of HPV vaccine series initiation and completion. Parental attitude score was the strongest predictor of HPV vaccine initiation among adolescents (adjusted odds ratio (aOR): 2.08; 95% confidence interval (CI): 1.80, 2.39). Other correlates that significantly predicted HPV series initiation were gender, study year, and intervention arm. Parental attitudes remained a significant predictor of receipt of 3 doses of HPV vaccine along with gender, race, school type and insurance type. This study demonstrates that positive parental attitudes are important predictors of HPV vaccination and critical to increasing coverage rates. Our findings suggest that more research is needed to understand how parental attitudes are developed and evolve over time.
PMCID: PMC4514386  PMID: 25912372
attitudes; adolescent; HPV vaccine; Health Belief Model; Theory of Reasoned Action
19.  Safety and Immunogenicity of Tetanus-Diphtheria-Acellular Pertussis Vaccine Administered to Children 10 or 11 Years of Age 
Clinical and Vaccine Immunology : CVI  2014;21(11):1560-1564.
Boosting immunity to tetanus, diphtheria, and pertussis through the use of Tdap vaccines is routinely recommended at 11 to 12 years of age; some states, however, require Tdap for entry into middle school, which may begin at 10 years of age. This study was conducted to determine whether Tdap5 (Adacel), which is licensed for use in children beginning at 11 years of age, is as safe and immunogenic in 10-year-olds as it is in 11-year-olds. Children who had received 5 previous doses of any diphtheria-tetanus-acellular pertussis (DTaP) vaccine were enrolled in a phase IV clinical trial; 646 10-year-olds and 645 11-year-olds completed the study, which involved a single intramuscular dose of Tdap5 along with pre- and postvaccination serologies. Postvaccination geometric mean concentrations (GMCs) of antibody to pertussis antigens (pertussis toxoid, filamentous hemagglutinin, pertactin, and fimbria types 2 and 3) of 10-year-olds were noninferior to those of 11-year-olds, as were booster response rates for all pertussis antibodies, except for those to fimbrial antigens (94% and 97%, respectively). Seroprotection rates among 10-year-olds for tetanus and diphtheria were noninferior to those in 11-year-olds. Rates of injection site reactions, solicited systemic reactions, and unsolicited adverse events, adverse reactions, and serious adverse events were similar in the two groups. These data support the conclusion that Tdap5 is safe and immunogenic in 10-year-olds. (This study has been registered at under registration no. NCT01311557.)
PMCID: PMC4248760  PMID: 25230939
20.  Post-licensure safety surveillance study of routine use of tetanus toxoid, reduced diphtheria toxoid and 5-component acellular pertussis vaccine 
Human Vaccines & Immunotherapeutics  2016;12(11):2742-2748.
An observational post-licensure (Phase IV) retrospective large-database safety study was conducted at Kaiser Permanente, a US integrated medical care organization, to assess the safety of Tetanus Toxoid, Reduced Diphtheria Toxoid and 5-Component Acellular Pertussis Vaccine (Tdap5) administered as part of routine healthcare among adolescents and adults. We evaluated incidence rates of various clinical events resulting in outpatient clinic, emergency department (ED), and hospital visits during various time intervals (windows) following Tdap5 vaccination using 2 pharmacoepidemiological methods (risk interval and historic cohort) and several screening thresholds. Plausible outcomes of interest with elevated incidence rate ratios (IRRs) were further evaluated by reviewing individual patient records to confirm the diagnosis, timing (temporal relationship), alternative etiology, and other health record details to discern possible relatedness of the health events to vaccination. Overall, 124,139 people received Tdap5 vaccine from September 2005 through mid-October 2006, and 203,154 in the comparison cohort received a tetanus and diphtheria toxoid adsorbed vaccine (and no live virus vaccine) during the year prior to initiation of this study. In the outpatient, ED and hospital databases, respectively, we identified 11/26, 179/700 and 187/700 unique health outcomes with IRRs significantly >1.0. Among the same unique health outcomes in the outpatient, ED, and hospital databases, 9, 146, and 385, respectively, had IRRs significantly <1.0. Further scrutiny of the outcomes with elevated IRRs did not reveal unexpected signals of adverse outcomes related to vaccination. In conclusion, Tdap5 vaccine was found to be safe among this large population of adolescents and adults.
PMCID: PMC5137522  PMID: 27388557
database screening; historical cohort; risk-interval cohort method; safety surveillance; Tdap vaccine
21.  Organizational correlates of adolescent immunization: Findings of a state-wide study of primary care clinics in North Carolina 
Vaccine  2013;31(40):4436-4441.
To analyze organization-level correlates of immunization coverage among adolescents served by high-volume primary care providers in North Carolina.
We randomly selected 91 clinics with at least 200 active records for patients ages 11–18 in the North Carolina Immunization Registry. For the 105,121 adolescents served by these clinics, we obtained immunization status for 6 vaccines, including human papillomavirus (HPV) vaccine (females only); meningococcal conjugate; and tetanus, diphtheria, and pertussis booster (Tdap).
Clinics specializing in pediatrics had higher coverage for meningococcal vaccine (OR = 1.79, 95% CI: 1.25–2.55), Tdap vaccine (OR = 1.22, 95% CI: 1.00–1.50), and childhood vaccines. However, pediatric clinics had lower coverage for HPV vaccine initiation (OR = 0.70, 95% CI: 0.52–0.94). Other correlates, which varied by vaccine, included policies related to vaccine documentation and the age at which clinics recommended vaccines.
Overall, adolescents were more likely to receive vaccines, except HPV vaccine, if they attended a pediatric clinic with supportive clinical policies.
PMCID: PMC3798154  PMID: 23845803
Adolescent health services; Diphtheria Tetanus acellular Pertussis Vaccine; Meningococcal Vaccine; Human papillomavirus Vaccine; Pediatrics; Family Practice
22.  Tetanus, Diphtheria, Acellular Pertussis Vaccine During Pregnancy: Pregnancy and Infant Health Outcomes 
The Journal of pediatrics  2013;163(5):1422-6.e1-4.
To assess pregnancy and birth outcomes in infants born to women who did or did not receive tetanus, diphtheria, acellular pertussis (Tdap) vaccine during pregnancy.
Study design
Retrospective cohort. Pregnant women 12-45 years of age who received Tdap at Intermountain Healthcare facilities and their infants were identified and compared with mother-infant pairs without documented Tdap from 5/2005-8/2009. Primary measures included pregnancy outcomes and infant health outcomes at birth through twelve months.
From 162,448 pregnancies we identified 138 women (0.08%) with documented Tdap administration during pregnancy (cases). 552 pregnant women without documented Tdap were randomly selected as controls. Of 138 immunized women, 63% received Tdap in the first trimester and 37% after. Tdap was given most commonly as wound prophylaxis. The incidence of spontaneous or elective abortion was no greater in Tdap cases than in controls. There were no significant differences in preterm delivery, gestational age, or birth weight between groups. One or more congenital anomaly was identified in 3.7% (95% CI 1.2%-8.5%) of case infants and 4.4% (95% CI 2.7%-6.5%) of control infants (p=0.749). In infants born to women receiving Tdap during pregnancy, 3.6% (0.8%-10.2%) had ICD-9-CM diagnoses consistent with complex chronic conditions within 12 months compared with 10.4% (95% CI 7.2-14.4%) of infants of controls (p=0.054).
Documented Tdap administration during pregnancy was uncommon and occurred most often in the first trimester as prophylaxis following trauma. No increase in adverse outcomes was identified in infants born to women receiving Tdap compared with infants of controls.
PMCID: PMC4102585  PMID: 23896191
maternal immunization; infant health outcomes; pregnancy outcomes; pertussis
23.  Universal tetanus, diphtheria, acellular pertussis (Tdap) vaccination of adults: What Canadian health care providers know and need to know 
Human Vaccines & Immunotherapeutics  2015;11(9):2167-2179.
The tetanus, diphtheria, and acellular pertussis vaccine (Tdap) is recommended for all adults in both Canada and the United States. There are few data on the proportion of Canadian adults vaccinated with Tdap; however, anecdotal reports indicate that uptake is low. This study aimed to explore the knowledge, attitudes, beliefs, and behaviors of Canadian health care providers (HCPs) in an attempt to identify potential barriers and facilitators to Tdap uptake. HCPs were surveyed and a geographic and practice representative sample was obtained (N =1,167). In addition, 8 focus groups and 4 interviews were conducted nationwide. Results from the survey indicate that less than half (47.5%) of all respondents reported being immunized with Tdap themselves, while 58.5% routinely offer Tdap to their adult patients. Knowledge scores were relatively low (63.2% correct answers). The best predictor of following the adult Tdap immunization guidelines was awareness of and agreement with those recommendations. Respondents who were aware of the recommendations were more likely to think that Tdap is safe and effective, that their patients are at significant risk of getting pertussis, and to feel that they have sufficient information (p < 0.0001 for each statement). Focus group data supported the survey results and indicated that there are substantial gaps in knowledge of pertussis and Tdap among Canadian HCPs. Lack of public knowledge about adult immunization, lack of immunization registries, a costing differential between Td and Tdap, workload required to deliver the vaccine, and vaccine hesitancy were identified as barriers to compliance with the national recommendations for universal adult immunization, and suggestions were provided to better translate recommendations to front-line practitioners.
PMCID: PMC4635841  PMID: 26090861
adult immunization; attitudes; beliefs; knowledge; pertussis; pertussis vaccine; Tdap; vaccine coverage
24.  Immunogenicity and safety results from a randomized multicenter trial comparing a Tdap-IPV vaccine (REPEVAX®) and a tetanus monovalent vaccine in healthy adults 
Human Vaccines & Immunotherapeutics  2012;8(12):1875-1881.
In adults with a tetanus-prone injury, combined vaccines such as Tdap-IPV (REPEVAX®) can boost immunity against several diseases simultaneously. This Phase IIIb, parallel-group, open-label trial compared antibody responses to Tdap-IPV and tetanus monovalent vaccine (TMV; Vaccin Tétanique Pasteur® or Tetavax®) against tetanus toxoid 10 and 28 d post-vaccination. Between July and December 2009, four centers in France and five in Germany recruited healthy adults who had received a tetanus-containing vaccine 5−10 y previously. Participants were randomized 1:1 to receive at the first visit a single dose (0.5 mL) of Tdap-IPV or TMV, with follow-up visits at Day 10 and Day 28. Outcomes: per protocol (PP) population immunogenicity at Day 10 (primary) and at Day 28 (secondary); safety throughout the study. Of 456 adults randomized, 223 received Tdap-IPV and 233 received TMV (PP population: 183 and 199 participants, respectively). All participants receiving Tdap-IPV and 99.0% receiving TMV had an anti-tetanus antibody concentration ≥ 0.1 IU/mL, confirming non-inferiority of Tdap-IPV to TMV (95% confidence interval of the difference: –1.2, 3.6). Number of adverse events reported was comparable in each group. Injection-site reactions were reported by 76.6% participants receiving Tdap-IPV and 74.6% receiving TMV. Systemic events (e.g., malaise, myalgia and headache) were reported in 47.7% and 39.7% of the Tdap-IPV and the TMV groups, respectively. Tdap-IPV is effective and well-tolerated for use in the management of tetanus-prone injuries in emergency settings in persons for whom a booster against diphtheria, pertussis and poliomyelitis is also needed. identifier: NCT00928785. Research sponsored by Sanofi Pasteur MSD.
PMCID: PMC3656080  PMID: 23032160
REPEVAX®; Tdap-IPV vaccine; immunogenicity; injuries; safety; tetanus toxoid
25.  Do correlates of HPV vaccine initiation differ between adolescent boys and girls? 
Vaccine  2012;30(41):5928-5934.
Guidelines now recommend that adolescents routinely receive human papillomavirus (HPV) vaccine. Because little is known about uptake among boys, we assessed HPV vaccine initiation in a population-based sample of adolescent boys and girls.
We analyzed weighted data from 751 parents who reported on an 11- to 17-year-old son or daughter for the 2010 North Carolina Child Health Assessment and Monitoring Program survey. Stratified multivariate logistic regression analyses identified correlates of HPV vaccine initiation separately for boys and girls.
Only 14% of sons had received one or more doses of HPV vaccine compared to 44% of daughters (p<0.01). For both sons and daughters, vaccine initiation correlated with age and having received meningococcal vaccine. Among sons, initiation of HPV vaccine was lower for those living in high income households (odds ratio [OR]=0.22, 95% CI, 0.09–0.53) and higher for those whose race was neither white nor black (OR=3.26, 95% CI, 1.06–10.04). When asked to give the main reason for not vaccinating their child against HPV, parents of unvaccinated sons were more likely than those of daughters to report not getting a provider’s recommendation or not being aware the vaccine was available for their child, but less likely to report concern about safety (p<0.01). At least 86% of unvaccinated children had missed an opportunity to receive HPV vaccine.
HPV vaccine correlates and concerns varied for parents of boys and girls. To improve very low levels of uptake among boys, providers should recommend HPV vaccine concomitant with other adolescent vaccines.
PMCID: PMC3438656  PMID: 22841973
adolescent health; human papillomavirus infections/prevention & control; vaccination/statistics & numerical data; North Carolina

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