Adolescent vaccination: coverage achieved by ages 13-15 years, and vaccinations received as recommended during ages 11-12 years, National Health Interview Survey 1997-2003

Successes and challenges in varicella vaccine

Varicella is a highly contagious disease caused by primary infection with varicella zoster virus (VZV). VZV infection, as well as varicella vaccination, induces VZV-specific antibody and T-cell-mediated immunity, essential for recovery. The immune responses developed contribute to protection following re-exposure to VZV. When cell-mediated immunity declines, as occurs with aging or immunosuppression, reactivation of VZV leads to herpes zoster (HZ). It has been almost 20 years since universal varicella vaccination has been implemented in many areas around the globe and this has resulted in a significant reduction of varicella-associated disease burden. Successes are reviewed here, whilst emphasis is put on the challenges ahead. Most countries that have not implemented routine childhood varicella vaccination have chosen to vaccinate high-risk groups alone. The main reasons for not introducing universal vaccination are discussed, including fear of age shift of peak incidence age and of HZ incidence increase. Possible reasons for not observing the predicted increase in HZ incidence are explored. The advantages and disadvantages of universal vs targeted vaccination as well as different vaccination schedules are discussed.

Minor consent and delivery of adolescent vaccines

PURPOSE

To explore whether, and to what extent, minor consent influences adolescent vaccine delivery in the United States.

METHODS

A telephone survey was completed by 263 professionals with responsibilities for adolescent health care and/or vaccination in 43 states. Measures included perceived frequency of unaccompanied minor visits and perceived likelihood of vaccine delivery to unaccompanied minors in hypothetical scenarios that varied by adolescent age, vaccine type, visit type, and clinical setting.

RESULTS

Among the 76 respondents most familiar with private primary care clinics, 47.1% reported perceptions that 17-year-old patients often present without a parent/legal guardian. Among the 104 respondents most familiar with public primary care clinics, 56.7% reported that 17-year-old patients often present alone. In response to hypothetical scenarios, approximately 30% of respondents familiar with private clinics and 50% of respondents familiar with public clinics reported perceptions that unaccompanied 17-year-old adolescents would not receive influenza, Tdap, or human papillomavirus vaccines during routine check-ups because they could not provide consent. Perceived likelihood of unaccompanied minors receiving vaccines when seen for confidential services in primary care, sexually transmitted disease, and Title X/family planning clinics varied significantly by vaccine type and clinical setting. On average, respondents reported that they would support minors having the ability to self-consent for vaccines at age 14.

CONCLUSIONS

The inability of minors to consent for vaccines is likely one barrier to vaccination. Interventions to increase adolescent vaccination should consider strategies that increase the ability of unaccompanied minors, particularly older minors, to receive vaccines within the context of legal, ethical, and professional guidelines.

The human papillomavirus (HPV) vaccine and cervical cancer: uptake and next steps

Infection with a high-risk type of the human papillomavirus (HPV) is a major contributing factor in the vast majority of cervical cancers. Dissemination of the HPV vaccine is critical in reducing the risk of the disease. This descriptive review of HPV vaccine uptake in papers published between 2006 and 2011 focuses on studies conducted in girls and young women. In the United States, rates of immunization as per the protocol for teens (age 13-17 years) range from 6% to 75% and those for young women (age 18-26 years) range from 4% to 79%, although the samples and data collection methods vary. The epidemiology of HPV, the mechanisms of action, protocols for vaccine immunization, rates of uptake, and barriers to vaccination at the policy, provider, and patient levels are reviewed. Various intervention techniques are described, and policy-level programs, such as legislation supporting mandates, subsidized public education, and cost-reduction initiatives, are also explored. Increased distribution of the HPV vaccine in school-based clinics, evidencebased scripts for provider counseling of young patients and their parents, concurrent immunizations to adolescents, prevention visits, greater patient education and outreach, and the dissemination of academic detailing can help to boost vaccine uptake, particularly in underresourced communities. Population-based surveillance is necessary for robust estimates of uptake over time. Additional research is needed to comprehensively examine socio-demographic, psychosocial, and sociocultural factors that predict vaccine uptake according to the protocol. Increased study of the vaccine's long-term effectiveness, in both males and females and among extended age groups, is warranted.

Attitudinal and demographic predictors of measles-mumps-rubella vaccine (MMR) uptake during the UK catch-up campaign 2008-09: cross-sectional survey

Background and Objective

Continued suboptimal measles-mumps-rubella (MMR) vaccine uptake has re-established measles epidemic risk, prompting a UK catch-up campaign in 2008–09 for children who missed MMR doses at scheduled age. Predictors of vaccine uptake during catch-ups are poorly understood, however evidence from routine schedule uptake suggests demographics and attitudes may be central. This work explored this hypothesis using a robust evidence-based measure.

Design

Cross-sectional self-administered questionnaire with objective behavioural outcome.

Setting and Participants

365 UK parents, whose children were aged 5–18 years and had received <2 MMR doses before the 2008–09 UK catch-up started.

Main Outcome Measures

Parents' attitudes and demographics, parent-reported receipt of invitation to receive catch-up MMR dose(s), and catch-up MMR uptake according to child's medical record (receipt of MMR doses during year 1 of the catch-up).

Results

Perceived social desirability/benefit of MMR uptake (OR = 1.76, 95% CI = 1.09–2.87) and younger child age (OR = 0.78, 95% CI = 0.68–0.89) were the only independent predictors of catch-up MMR uptake in the sample overall. Uptake predictors differed by whether the child had received 0 MMR doses or 1 MMR dose before the catch-up. Receipt of catch-up invitation predicted uptake only in the 0 dose group (OR = 3.45, 95% CI = 1.18–10.05), whilst perceived social desirability/benefit of MMR uptake predicted uptake only in the 1 dose group (OR = 9.61, 95% CI = 2.57–35.97). Attitudes and demographics explained only 28% of MMR uptake in the 0 dose group compared with 61% in the 1 dose group.

Conclusions

Catch-up MMR invitations may effectively move children from 0 to 1 MMR doses (unimmunised to partially immunised), whilst attitudinal interventions highlighting social benefits of MMR may effectively move children from 1 to 2 MMR doses (partially to fully immunised). Older children may be best targeted through school-based programmes. A formal evaluation element should be incorporated into future catch-up campaigns to inform their continuing improvement.

Receipt of tetanus-containing vaccinations among adolescents aged 13 to 17 years in the United States: National Immunization Survey-Teen 2007

BACKGROUND

Tetanus-diphtheria-acellular pertussis (Tdap) was licensed in the United States in 2005 to be given in place of tetanus-diphtheria (Td) for single use in adolescents.

OBJECTIVES

This analysis was conducted to determine vaccination coverage with Td and Tdap among adolescents in the United States aged 13 to 17 years and to characterize adolescents who had not received a tetanus-containing booster vaccine.

METHODS

Data were analyzed from the National Immunization Survey-Teen (NIS-Teen) 2007, a random-digit-dialing telephone survey that is weighted to be nationally representative of adolescents aged 13 to 17 years. Parents gave verbal consent so that vaccination providers could be contacted to obtain the adolescents' immunization histories. Weighted coverage of Td and Tdap vaccines was estimated with bivariate analysis from returned vaccination data from the providers' records. A multivariable analysis was conducted to determine factors independently associated with nonreceipt of tetanus-containing vaccines. Missed opportunities for vaccination with Td or Tdap were determined from documented vaccination visits for other vaccines.

RESULTS

Out of 69,289 households screened, 6572 had an eligible adolescent aged 13 to 17 years and 5486 (83.5%) completed the household interview. Among 5474 adolescents who met the age criterion and completed a household interview, consent to contact providers was obtained for 4114 (75.2%). A total of 2947 adolescents (53.7% of those with completed household interviews) had immunization histories returned from providers for verification. In 2007, a total of 2149 adolescents (weighted percentage, 72.3%) aged 13 to 17 years had received at least one tetanus booster since age 10 years; Tdap coverage was 30.4%. The mean (SE) age at Td or Tdap receipt was 13.04 (0.04) years (range, 10.00-17.84 years); the median age was 12.86 years. More than half (59.4%) of sampled adolescents had received their booster dose on or after January 1, 2005; among those vaccinated in 2007, 89.1% received Tdap as their booster dose. Factors associated with nonreceipt of Td or Tdap included geographic location and not having a provider-reported well-child visit at ages 11 to 12 years.

CONCLUSIONS

Almost three quarters of adolescents aged 13 to 17 years included in the NIS-Teen 2007 received a tetanus-containing vaccine, and almost one third received Tdap. Among adolescents who received a tetanus-containing vaccine in 2007, a total of 89.1% received the new Tdap vaccine in place of Td, as recommended. Adolescents not receiving Td or Tdap may face barriers to accessing health care. Research is needed to identify evidence-based strategies to improve vaccination coverage among adolescents.

Examining future adolescent human papillomavirus vaccine uptake, with and without a school mandate

PURPOSE

To develop a model of adolescent (HPV) human papillomavirus vaccine utilization that explored future HPV vaccination rates, with and without a school mandate, for the vaccine at middle school entry.

METHODS

A dynamic, population-based, compartmental model was developed that estimated over a 50-year time horizon HPV vaccine uptake among female adolescents living in the United States. The model incorporated data on parental attitudes about this vaccine and adolescent health care utilization levels.

RESULTS

Without a mandate, our model predicted that 70% coverage, a lower threshold value used in many previous modeling studies of HPV vaccination, would not be achieved until a mean of 23 years after vaccine availability. Maximal coverage of 79% was achieved after 50 years. With a school mandate in place, utilization increased substantially, with 70% vaccination coverage achieved by year 8 and maximal vaccination coverage, 90%, achieved by year 43.

CONCLUSIONS

Our results suggest that vaccine utilization is likely to be low for several years, though strong school mandates might improve HPV vaccine uptake. These results affect the interpretation of previous modeling studies that estimated the potential clinical effects of HPV vaccination under assumptions of very high vaccine utilization rates.

Immunization updates and challenges

PURPOSE OF REVIEW

Childhood vaccination recommendations in the United States have increased throughout the years. Many providers, patients, and families are overwhelmed and have concerns regarding the safety and efficacy of vaccines. Various barriers and challenges exist for healthcare providers to successfully implement the vaccination recommendations. This review will discuss the 2009 and newly released 2010 immunization recommendations, as well as challenges and strategies to improve vaccination in children and adolescents.

RECENT FINDINGS

Seasonal influenza immunization continues to be promoted for all children, and recommendations for vaccination against novel influenza A have emerged as well. Concerns surrounding vaccine safety and necessity may cause increasing rates of vaccine refusal among some parents, but clear messages from providers and unbiased information about benefits and risks of immunization may counteract these doubts. Barriers to immunizing adolescents continue as access to healthcare in this age group changes.

SUMMARY

Pediatric providers currently face numerous challenges in improving rates of immunization among children and adolescents. Promoting coverage through the influenza vaccines, counseling parents with clear information about the risks and benefits of vaccines, and taking advantage of nonpreventive visits for immunization are some strategies suggested to address these challenges.

Mumps resurgences in the United States: A historical perspective on unexpected elements

In 2006 the United States experienced the largest nationwide mumps epidemic in 20 years, primarily affecting college dormitory residents. Unexpected elements of the outbreak included very abrupt time course (75% of cases occurred within 90 days), geographic focality (85% of cases occurred in eight rural Midwestern states), rapid upward and downward shift in peak age-specific attack rate (5-9-year olds to 18-24-year olds, then back), and two-dose vaccine failure (63% of case-patients had received two doses). To construct a historical context in which to understand the recent outbreak, we reviewed US mumps surveillance data, vaccination coverage estimates, and relevant peer-reviewed literature for the period 1917-2008. Many of the unexpected features of the 2006 mumps outbreak had been reported several times previously in the US, e.g., the 1986-1987 mumps resurgence had extremely abrupt onset, rural geographic focality, and an upward-then-downward age shift. Evidence suggested recurrent mumps outbreak patterns were attributable to accumulation of susceptibles in dispersed situations where the risk of endemic disease exposure was low and were triggered when this susceptible population was brought together in crowded living conditions. The 2006 epidemic followed this pattern, with two unique variations: it was preceded by a period of very high vaccination rates and very low disease incidence and was characterized by two-dose failure rates among adults vaccinated in childhood. Data from the past 80 years suggest that preventing future mumps epidemics will depend on innovative measures to detect and eliminate build-up of susceptibles among highly vaccinated populations.

Parents' views on 3 shot-related visits: implications for use of adolescent vaccines like human papillomavirus vaccine

OBJECTIVE

Multidose adolescent-targeted vaccines, for example the human papillomavirus (HPV) vaccine, require parents and adolescents to have repeated interactions with the physician's office. We sought to evaluate parental views on participating in frequent vaccine-related encounters and their preferences for how these encounters should ideally be implemented.

METHODS

A Web-based survey about a hypothetical 3-dose adolescent vaccine was provided to a national sample of 1025 US parents of adolescents (aged 9-17 years) in 2007.

RESULTS

Survey completion rate among parents was 69%. Most (86%) were amenable to having their adolescent visit the provider's office at least 3 times in a year for vaccination. The highest proportion of parents (47%) preferred that the first dose be administered at a comprehensive doctor visit, followed by 2 nurse "shots-only" visits. However, many parents (30%) wanted each dose to be given as part of a comprehensive visit with a physician. The most commonly cited barriers included a belief that healthy adolescents needn't be seen frequently in the doctor's office (15%) and concerns about missing school (14%).

CONCLUSIONS

Compliance with multidose adolescent vaccines like HPV could require a shift in the expected frequency of health care visits. Our results suggest that most parents are amenable to more frequent adolescent vaccine-related visits, though the feasibility of implementing these visits within the current medical system remains to be determined.

Determining accurate vaccination coverage rates for adolescents: the National Immunization Survey-Teen 2006

Since 1994, the Centers for Disease Control and Prevention has funded the National Immunization Survey (NIS), a large telephone survey used to estimate vaccination coverage of U.S. children aged 19-35 months. The NIS is a two-phase survey that obtains vaccination receipt information from a random-digit-dialed survey, designed to identify households with eligible children, followed by a provider record check, which obtains provider-reported vaccination histories for eligible children. In 2006, the survey was expanded for the first time to include a national sample of adolescents aged 13-17 years, called the NIS-Teen. This article summarizes the methodology used in the NIS-Teen. In 2008, the NIS-Teen was expanded to collect state-specific and national-level data to determine vaccination coverage estimates. This survey provides valuable information to guide immunization programs for adolescents.

Hepatitis B vaccination coverage among U.S. adolescents, National Immunization Survey-Teen, 2006

PURPOSE

To determine national estimates of hepatitis B vaccination among adolescents in the United States and factors associated with vaccination using provider-reported immunization histories.

METHODS

Data were analyzed from the 2006 National Immunization Survey-Teen, a random-digit-dialed telephone survey sampling households with adolescents aged 13-17 years. Provider-reported immunization histories were obtained to determine hepatitis B vaccination coverage.

RESULTS

The household response rate was 56.2% (n = 5468); provider data was obtained from 52.7% (n = 2882). Overall up-to-date hepatitis B vaccination coverage was 81.3%; older adolescents aged 15-17 years old had lower coverage than younger adolescents aged 13-14 years old, (77.6% vs. 87.1%, p < .05). More than half of the 13-14-year-olds had received vaccination before age 3 years, while 15-17-year-olds received vaccination throughout childhood. Factors associated with vaccination coverage among adolescents 13-14 years old included private health insurance coverage and having a parent-reported health care visit at age of 11-12 years. Factors associated with vaccination coverage among adolescents 15-17 years old included living in the Northeast, having a mother who was married, and having a parent-reported health care visit at 11-12 years.

CONCLUSIONS

In 2006, adolescents 15-17 years old had lower hepatitis B vaccination coverage compared to those 13-14 years old. Younger adolescents likely benefited from universal recommendations in 1991 and received hepatitis B vaccination during early childhood. A healthcare visit at age 11-12 years has been recommended by professional organizations and was associated with hepatitis B vaccination in our survey. Parents and providers should routinely review adolescent immunizations.

Varicella vaccination in Europe - taking the practical approach

Varicella is a common viral disease affecting almost the entire birth cohort. Although usually self-limiting, some cases of varicella can be serious, with 2 to 6% of cases attending a general practice resulting in complications. The hospitalisation rate for varicella in Europe ranges from 1.3 to 4.5 per 100,000 population/year and up to 10.1% of hospitalised patients report permanent or possible permanent sequelae (for example, scarring or ataxia). However, in many countries the epidemiology of varicella remains largely unknown or incomplete. In countries where routine childhood vaccination against varicella has been implemented, it has had a positive effect on disease prevention and control. Furthermore, mathematical models indicate that this intervention strategy may provide economic benefits for the individual and society. Despite this evidence and recommendations for varicella vaccination by official bodies such as the World Health Organization, and scientific experts in the field, the majority of European countries (with the exception of Germany and Greece) have delayed decisions on implementation of routine childhood varicella vaccination, choosing instead to vaccinate high-risk groups or not to vaccinate at all. In this paper, members of the Working Against Varicella in Europe group consider the practicalities of introducing routine childhood varicella vaccination in Europe, discussing the benefits and challenges of different vaccination options (vaccination vs. no vaccination, routine vaccination of infants vs. vaccination of susceptible adolescents or adults, two doses vs. one dose of varicella vaccine, monovalent varicella vaccines vs. tetravalent measles, mumps, rubella and varicella vaccines, as well as the optimal interval between two doses of measles, mumps, rubella and varicella vaccines). Assessment of the epidemiology of varicella in Europe and evidence for the effectiveness of varicella vaccination provides support for routine childhood programmes in Europe. Although European countries are faced with challenges or uncertainties that may have delayed implementation of a childhood vaccination programme, many of these concerns remain hypothetical and with new opportunities offered by combined measles, mumps, rubella and varicella vaccines, reassessment may be timely.