Hepatitis B Vaccination of Low Birth Weight Infants in Washington State.

OBJECTIVE: The U.S. Advisory Committee on Immunization Practices (ACIP) recommends that infants born weighing less than 2,000 g receive the hepatitis B (HepB) vaccine at hospital discharge or 30 days of age. This study aimed to assess timely HepB vaccination among low birth weight infants. We hypothesized that many of these vulnerable infants would fail to receive their HepB birth dose on time. STUDY DESIGN: This retrospective cohort study included Washington State infants born weighing less than 2,000 g at an academic medical center between 2008 and 2013. Data were abstracted from electronic health records and linked to vaccine data from the Washington State Immunization Information System. Multivariable logistic regression was used to examine the associations between sociodemographic, clinical, and visit characteristics and HepB vaccination by birth hospitalization discharge or 30 days of age. RESULTS: Among 976 study infants, 58.4% received their HepB vaccine by birth hospitalization discharge or 30 days of age. Infants had higher odds of timely HepB vaccination if they were Hispanic (adjusted odds ratio [AOR] = 1.80, 95% confidence interval [CI]: 1.10-2.95) or non-Hispanic black (AOR = 2.28, 95% CI: 1.36-3.80) versus non-Hispanic white or if they were hospitalized 14 days or longer versus less than 14 days (AOR = 2.43, 95% CI: 1.66-3.54). Infants had lower odds of timely HepB vaccination if they were born before 34 weeks versus on or after 34 weeks of gestational age (AOR = 0.41, 95% CI: 0.27-0.63) or if they had an estimated household income less than $50,845 versus 50,845 or greater (AOR = 0.64, 95% CI: 0.48-0.86). CONCLUSION: Many infants born weighing less than 2,000 g did not receive their first HepB birth dose according to ACIP recommendations. Strategies are needed to improve timely HepB vaccination in this high-risk population. KEY POINTS: · Low birth weight infants are at increased risk for vaccine preventable diseases.. · Many of these vulnerable infants failed to receive their first hepatitis B vaccine on time.. · This study identified key factors associated with timely hepatitis B vaccination..

A Risk Prediction Model to Identify Newborns at Risk for Missing Early Childhood Vaccinations.

BACKGROUND: Approximately 30% of US children aged 24 months have not received all recommended vaccines. This study aimed to develop a prediction model to identify newborns at high risk for missing early childhood vaccines. METHODS: A retrospective cohort included 9080 infants born weighing ≥2000 g at an academic medical center between 2008 and 2013. Electronic medical record data were linked to vaccine data from the Washington State Immunization Information System. Risk models were constructed using derivation and validation samples. K-fold cross-validation identified risk factors for model inclusion based on alpha = 0.01. For each patient in the derivation set, the total number of weighted adverse risk factors was calculated and used to establish groups at low, medium, or high risk for undervaccination. Logistic regression evaluated the likelihood of not completing the 7-vaccine series by age 19 months. The final model was tested using the validation sample. RESULTS: Overall, 53.6% failed to complete the 7-vaccine series by 19 months. Six risk factors were identified: race/ethnicity, maternal language, insurance status, birth hospitalization length of stay, medical service, and hepatitis B vaccine receipt. Likelihood of non-completion was greater in the high (77.1%; adjusted odds ratio [AOR] 5.6; 99% confidence interval [CI]: 4.2, 7.4) and medium (52.7%; AOR 1.9; 99% CI: 1.6, 2.2) vs low (38.7%) risk groups in the derivation sample. Similar results were observed in the validation sample. CONCLUSIONS: Our prediction model using information readily available in birth hospitalization records consistently identified newborns at high risk for undervaccination. Early identification of high-risk families could be useful for initiating timely, tailored vaccine interventions.

Time and geographic variations in human papillomavirus vaccine uptake in Washington state.

This study examines geographic variations of human papillomavirus (HPV) vaccine uptake, the most significant disparity in HPV vaccination, in Washington State. We evaluated Washington State Immunization Information System (WA-IIS) data on target age (11-12 year old adolescents) between 2008 and 2018. A Bayesian spatio-temporal analysis was conducted to examine uptake at the census tract level. Urban-rural disparities in vaccine rates were assessed using t-tests. Persistently high and low vaccine areas and their contributing sociodemographic factors were then identified using a multinomial logistic regression. HPV vaccine uptake gradually increased after 2010, but remained persistently low. Average vaccine uptake rates from 2010 through 2018 in urban areas were 11%-34% for initiation and 4-19% for completion. These rates were 9-22% initiation and 3-11% completion in rural areas. We observed statistically significant (p < 0.05) differences between the estimated vaccine rates for urban and rural census tracts. Race/ethnicity and socioeconomic status were associated with this urban-rural disparity. The odds of being in low vaccine rural areas increased with increase in Area Deprivation Index (ADI) (OR = 1.14, CI = (1.10, 1.19)), and decreased with percentage increase in Black (OR = 0.43, CI = (0.02, 0.85)) and Hispanic (OR = 0.97, CI = (0.94, 1.00)) population. Bayesian spatial analysis was effective in capturing spatio-temporal patterns in HPV vaccine rates and identifying areas with persistently low vaccination over time. This analytic approach can be used to guide public health policies and geographically target interventions to reduce HPV vaccine disparities and to prevent future HPV-related cancers.

Influenza-Related Knowledge, Beliefs, and Experiences Among Caregivers of Hospitalized Children.

OBJECTIVE: Caregivers frequently decline influenza vaccine for their hospitalized child. In this study, we aimed to examine factors impacting their influenza vaccine decision-making. METHODS: We conducted a cross-sectional survey study of English- and Spanish-speaking caregivers of children hospitalized at a tertiary care pediatric hospital between November 2017 and April 2018. The survey assessed influenza-related knowledge, beliefs, experiences, and vaccine hesitancy. Multivariable logistic regression examined associations between survey responses and child influenza vaccination status at admission (already vaccinated versus not yet vaccinated this season) and, among caregivers with vaccine-eligible children, influenza vaccine acceptance (versus declination) for their child during hospitalization. RESULTS: Caregivers (N =522; 88.9% response rate) were mostly non-Hispanic white (66.9%) and English-speaking (97.7%). At admission, 63.2% of children were already vaccinated this season. The caregiver view that influenza vaccination is important for their child's health was the strongest positive predictor of having an already vaccinated child (adjusted odds ratio [aOR]: 3.16; 95% confidence interval [CI]: 2.46-4.05); vaccine hesitancy was the strongest negative predictor (aOR: 0.61; 95% CI: 0.50-0.75). Among caregivers with vaccine-eligible children, 30.3% accepted influenza vaccine for their hospitalized child. Their belief regarding the child health benefits of influenza vaccination was associated with vaccine acceptance during hospitalization (aOR: 6.87; 95% CI: 3.38-13.96). Caregiver vaccine hesitancy and agreement that children with mild illness should delay vaccination negatively impacted vaccine acceptance (aOR: 0.39; 95% CI: 0.25-0.62; aOR: 0.33; 95% CI: 0.20-0.56, respectively). CONCLUSIONS: We identified key factors impacting influenza vaccine decision-making among caregivers of hospitalized children, a critical step to improving uptake in this population.

Vaccination Status and Resource Use During Hospital Visits for Respiratory Illnesses.

OBJECTIVES: To evaluate variation in resource use for children with acute respiratory tract illness (ARTI) by vaccination status. METHODS: We conducted a retrospective cohort study of children 0 to 16 years of age at 5 children's hospitals with 1 of 4 ARTI diagnoses (pneumonia, croup, asthma, and bronchiolitis) between July 2014 and June 2016. The predictor variable was provider-documented up-to-date (UTD) vaccination status (yes or no). Outcomes were receipt of each of the following tests or treatments (yes or no): complete blood cell count, blood cultures, C-reactive protein (CRP) level testing, viral testing, influenza testing, pertussis testing, chest radiographs, neck radiographs, antibiotics, and corticosteroids. We generated multivariable logistic regression models to examine the associations between our predictor and outcomes. RESULTS: Of the 2302 participants included in analysis, 568 (25%) were diagnosed with pneumonia, 343 (15%) were diagnosed with croup, 653 (28%) were diagnosed with asthma, and 738 (32%) were diagnosed with bronchiolitis. Most (92%) vaccination statuses were documented as UTD. Across conditions, children whose vaccination status was documented as not UTD had higher adjusted odds of receiving a complete blood cell count, blood culture, CRP level testing, and influenza testing (P < .001). Children with pneumonia whose vaccination status was documented as not UTD had higher adjusted odds of receiving CRP level testing and influenza testing (P < .001). Children with croup whose vaccination status was documented as not UTD had higher adjusted odds of receiving blood cultures (P < .001). CONCLUSIONS: Children with ARTI whose vaccination status was documented as not UTD had higher odds of undergoing laboratory testing compared with children whose vaccination status was documented as UTD.

Hepatitis B Birth Dose: First Shot at Timely Early Childhood Vaccination.

INTRODUCTION: Current U.S. recommendations state that newborns weighing ≥2,000 grams should receive a birth dose of hepatitis B vaccine, yet approximately one quarter do not receive this first dose as scheduled. The relationship between timely receipt of the first hepatitis B vaccine and other early childhood vaccines remains unclear. METHODS: Washington State newborns (birth weight ≥2,000 grams) who received birth hospitalization care at an urban academic medical center between 2008 and 2013 were included. Multivariable logistic regression was used to assess whether hepatitis B vaccine receipt during the birth hospitalization was associated with completing the seven-vaccine series by 19 months, adjusting for select sociodemographic, clinical, and birth hospitalization characteristics. Analyses were conducted in 2017-2018. RESULTS: Of the 9,080 study participants, 75.5% received hepatitis B vaccine during the birth hospitalization, and 53.6% completed the seven-vaccine series by 19 months. Overall, 60.0% of infants vaccinated against hepatitis B during the birth hospitalization completed the seven-vaccine series by 19 months compared with 33.8% of those who were unvaccinated at discharge (p<0.001). The odds of series completion were nearly 3 times higher among infants who received versus did not receive hepatitis B vaccine during the birth hospitalization (AOR=2.92, 95% CI=2.61, 3.26). CONCLUSIONS: Infants who received hepatitis B vaccine during their birth hospitalization had higher odds of receiving all recommended vaccines by 19 months independent of other factors associated with vaccine receipt. Understanding the factors that influence this first parental vaccine decision and how hepatitis B vaccine delay or declination may affect subsequent vaccination requires further research.

Early Childhood Vaccination Status of Preterm Infants.

BACKGROUND: Preterm infants are at increased risk for vaccine-preventable infections and associated complications. Limited studies describe timely vaccination of these vulnerable infants. METHODS: This retrospective cohort study included Washington State infants with birth hospitalizations at an urban academic medical center between 2008 and 2013. Demographic, clinical, and visit data from electronic health records were linked to vaccine data from the Washington State Immunization Information System. Completion of the recommended 7-vaccine series by 19 months of age was compared between preterm infants (born at <37 weeks' gestation) and term/postterm infants (born at 37-43 weeks' gestation) by using Pearson's χ2 test and multivariable logistic regression. Secondary outcomes included 7-vaccine series completion by 36 months of age and receipt of individual vaccines in the series. Rotavirus, hepatitis A, and influenza vaccination was also assessed. RESULTS: Of study infants (n = 10 367), 19.3% were born prematurely. Preterm infants had lower 7-vaccine series completion compared with term/postterm infants by 19 months (47.5% vs 54.0%; adjusted odds ratio 0.77 [95% confidence interval 0.65-0.90]) and 36 months (63.6% vs 71.3%; adjusted odds ratio 0.73 [95% confidence interval 0.61-0.87]). Early preterm (23-33 weeks' gestation) and late preterm (34-36 weeks' gestation) infants had a lower rate of 7-vaccine series completion compared with term/postterm infants. Full influenza vaccination coverage by 19 months also differed between groups (early preterm: 47.7%; late preterm: 41.5%; term/postterm: 44.7%; P = .02). CONCLUSIONS: Over half of preterm infants were undervaccinated at 19 months; one-third failed to catch up by 36 months. Strategies to improve vaccination of these high-risk infants are needed.

Sociodemographic, clinical and birth hospitalization characteristics and infant Hepatitis B vaccination in Washington State.

OBJECTIVE: Hepatitis B (HepB) vaccine is recommended at birth; however, national coverage estimates fall far below target levels. Studies describing the factors associated with infant HepB vaccination are lacking. This study aimed to identify the sociodemographic, clinical and birth hospitalization factors associated with timely receipt of the first HepB vaccine dose. STUDY DESIGN: This retrospective cohort study included Washington State infants born weighing ≥2000 g who received birth hospitalization care at an urban academic medical center between January 2008-December 2013. Multivariable logistic regression was used to estimate adjusted odds ratios (AOR) and 95% confidence intervals (CI) for associations between maternal and infant characteristics and HepB vaccine receipt during the birth hospitalization. RESULTS: Of the 9080 study infants, 75.5% received HepB vaccine during the birth hospitalization. Infants had higher odds of being vaccinated during the birth hospitalization if they were Hispanic (AOR 2.08; CI: 1.63, 2.65), non-Hispanic black (AOR 2.34; CI: 1.93, 2.84) or Asian (AOR 2.70; CI: 2.22, 3.28) compared to non-Hispanic white. Infants with a Spanish- vs. English-speaking mother (AOR 1.97; CI: 1.46, 2.68), public vs. private insurance (AOR 2.01; CI: 1.78, 2.29), and those hospitalized ≥96 h vs. 24 to <48 h (AOR 1.67; CI: 1.34, 2.09) also had higher odds of vaccination. CONCLUSIONS: Populations that are typically underserved (e.g., publicly insured, racial/ethnic minorities) had higher odds of receiving HepB vaccine during the birth hospitalization. These findings may aid in identifying high-risk infants who could benefit from targeted interventions to increase initial HepB vaccination.

Accuracy of Provider-Documented Child Immunization Status at Hospital Presentation for Acute Respiratory Illness.

OBJECTIVES: To assess (1) the accuracy of child immunization status documented by providers at hospital presentation for acute respiratory illness and (2) the association of provider-documented up-to-date (UTD) status with immunization receipt during and after hospitalization. METHODS: We conducted a retrospective cohort analysis of children ≤16 years old treated for asthma, croup, bronchiolitis, or pneumonia at a children's hospital between July 2014 and June 2016. Demographics, clinical characteristics, and provider-documented UTD immunization status (yes or no) at presentation were obtained from the medical record. We compared provider-documented UTD status to the gold standard: the child's UTD status as documented in the Washington State Immunization Information System (WAIIS). The sensitivity, specificity, and positive predictive value of provider-documented UTD status were calculated. We assessed the association of provider-documented UTD status and immunization during and within 30 days posthospitalization using multivariable logistic regression. RESULTS: Among 478 eligible children, 450 (94%) had provider-documented UTD status at hospital presentation and an active WAIIS record. Overall, 92% and 42% were UTD by provider documentation and WAIIS records, respectively, with provider-documented UTD status having 98.4% sensitivity (95% confidence interval [CI]: 95.4%-99.7%), 12.2% specificity (95% CI: 8.5%-16.8%), and 44.6% positive predictive value (95% CI: 39.7%-49.5%). Per WAIIS records, 20% and 44% of children who were due for vaccines received a vaccine during or within 30 days posthospitalization, respectively. There was no significant association between provider-documented UTD status and immunization during or after hospitalization. CONCLUSIONS: Provider-documented UTD immunization status at hospital presentation for children with respiratory illnesses overestimates UTD status, creating missed opportunities for immunization during and after hospitalization.

Exemptions From Mandatory Immunization After Legally Mandated Parental Counseling.

BACKGROUND: The success of health care provider counseling-based interventions to address vaccine hesitancy is not clear. In 2011, Washington State implemented Senate Bill 5005 (SB5005), requiring counseling and a signed form from a licensed health care provider to obtain an exemption. Evaluating the impact of a counseling intervention can provide important insight into population-level interventions that focus on interpersonal communication by a health care provider. METHODS: We used segmented regression and interaction and aggregation indices to assess the impact of SB5005 on immunization coverage and exemption rates in Washington State from school years 1997-1998 through 2013-2014. RESULTS: After SB5005 was implemented, there was a significant relative decrease of 40.2% (95% confidence interval: -43.6% to -36.6%) in exemption rates. This translates to a significant absolute reduction of 2.9 percentage points (95% confidence interval: -4.2% to -1.7%) in exemption rates. There were increases in vaccine coverage for all vaccines required for school entrance, with the exception of the hepatitis B vaccine. The probability that kindergarteners without exemptions would encounter kindergarteners with exemptions (interaction index) decreased, and the probability that kindergarteners with exemptions would encounter other such kindergarteners (aggregation index) also decreased after SB5005. Moreover, SB5005 was associated with a decline in geographic clustering of vaccine exemptors. CONCLUSIONS: States in the United States and jurisdictions in other countries should consider adding parental counseling by health care provider as a requirement for obtaining exemptions to vaccination requirements.

The Challenges in Measuring Local Immunization Coverage: A Statewide Case Study.

There are many forms of existing immunization surveillance in the United States and Washington state, but all are limited in their ability to provide timely identification of clusters of unimmunized individuals and assess the risk of vaccine-preventable diseases. This article aims to: (1) describe challenges to measuring immunization coverage at a local level in the United States using Washington State as a case study; and (2) propose improvements to existing surveillance systems that address the challenges identified.

Impact of a pertussis epidemic on infant vaccination in Washington state.

BACKGROUND AND OBJECTIVES: Washington State experienced a pertussis epidemic from October 2011 to December 2012. There was wide variation in incidence by county. The objectives of this study were to determine how the pertussis epidemic affected infant vaccination in Washington State and whether the incidence in counties modified this effect. METHODS: We conducted an ecologic before-after study to compare the proportion of infants up to date (UTD) with a pertussis-containing vaccine at time points before (September 30, 2011), during (September 30, 2012), and after (September 30, 2013) the epidemic. Children aged 3 to 8 months enrolled in the Washington State Immunization Information System with documented county of residence were included. UTD status was determined as ≥ 1, ≥ 2, or ≥ 3 doses of a pertussis-containing vaccine at ages 3, 5, and 7 months, respectively. Generalized linear models with extension to the binomial family and clustered robust standard errors were used to examine differences in the proportion of UTD infants between preepidemic and either epidemic or postepidemic points. The potential modifying effect of pertussis incidence by county was examined. RESULTS: We found no significant difference in statewide UTD status with a pertussis-containing vaccine between preepidemic and either epidemic (absolute difference 2.1%; 95% confidence interval, -1.6 to 5.9) or postepidemic (absolute difference 0.2%; 95% confidence interval, -4.0 to 4.5) time points. There was no significant modification by county pertussis incidence. There was wide variation in the absolute difference in UTD status across counties. CONCLUSIONS: A statewide pertussis epidemic does not appear to have significantly changed the proportion of infants who were UTD with a pertussis-containing vaccine.

Association of vaccine-related attitudes and beliefs between parents and health care providers.

OBJECTIVES: Health care providers influence parental vaccination decisions. Over 90% of parents report receiving vaccine information from their child's health care provider. The majority of parents of vaccinated children and children exempt from school immunization requirements report their child's primary provider is a good source for vaccine information. The role of health care providers in influencing parents who refuse vaccines has not been fully explored. The objective of the study was to determine the association between vaccine-related attitudes and beliefs of health care providers and parents. METHODS: We surveyed parents and primary care providers of vaccinated and unvaccinated school age children in four states in 2002-2003 and 2005. We measured key immunization beliefs including perceived risks and benefits of vaccination. Odds ratios for associations between parental and provider responses were calculated using logistic regression. RESULTS: Surveys were completed by 1367 parents (56.1% response rate) and 551 providers (84.3% response rate). Parents with high confidence in vaccine safety were more likely to have providers with similar beliefs, however viewpoints regarding disease susceptibility and severity and vaccine efficacy were not associated. Parents whose providers believed that children get more immunizations than are good for them had 4.6 higher odds of holding that same belief compared to parents whose providers did not have that belief. CONCLUSIONS: The beliefs of children's health care providers and parents, including those regarding vaccine safety, are similar. Provider beliefs may contribute to parental decisions to accept, delay or forgo vaccinations. Parents may selectively choose providers who have similar beliefs to their own.

Are Recent Medical Graduates More Skeptical of Vaccines?

Rates of delay and refusal of recommended childhood vaccines are increasing in many U.S. communities. Children's health care providers have a strong influence on parents' knowledge, attitudes, and beliefs about vaccines. Provider attitudes towards immunizations vary and affect their immunization advocacy. One factor that may contribute to this variability is their familiarity with vaccine-preventable diseases and their sequelae. The purpose of this study was to investigate the association of health care provider year of graduation with vaccines and vaccine-preventable disease beliefs. We conducted a cross sectional survey in 2005 of primary care providers identified by parents of children whose children were fully vaccinated or exempt from one or more school immunization requirements. We examined the association of provider graduation cohort (5 years) with beliefs on immunization, disease susceptibility, disease severity, vaccine safety, and vaccine efficacy. Surveys were completed by 551 providers (84.3% response rate). More recent health care provider graduates had 15% decreased odds of believing vaccines are efficacious compared to graduates from a previous 5 year period; had lower odds of believing that many commonly used childhood vaccines were safe; and 3.7% of recent graduates believed that immunizations do more harm than good. Recent health care provider graduates have a perception of the risk-benefit balance of immunization, which differs from that of their older counterparts. This change has the potential to be reflected in their immunization advocacy and affect parental attitudes.

Vaccine refusal, mandatory immunization, and the risks of vaccine-preventable diseases.

Vaccines are among the most effective prevention tools available to clinicians. However, the success of an immunization program depends on high rates of acceptance and coverage. There is evidence of an increase in vaccine refusal in the United States and of geographic clustering of refusals that results in outbreaks. Children with exemptions from school immunization requirements (a measure of vaccine refusal) are at increased risk for measles and pertussis and can infect others who are too young to be vaccinated, cannot be vaccinated for medical reasons, or were vaccinated but did not have a sufficient immunologic response. Clinicians can play a crucial role in parental decision making. Health care providers are cited as the most frequent source of immunization information by parents, including parents of unvaccinated children. Although some clinicians have discontinued or have considered discontinuing their provider relationship with patients who refuse vaccines, the American Academy of Pediatrics Committee on Bioethics advises against this and recommends that clinicians address vaccine refusal by respectfully listening to parental concerns and discussing the risks of nonvaccination.

Vaccine knowledge and practices of primary care providers of exempt vs. vaccinated children.

OBJECTIVES: Compare vaccine knowledge, attitudes and practices of primary care providers for fully vaccinated children and children who are exempt from school immunization requirements. METHODS: We conducted a mailed survey of parent-identified primary care providers from four states to measure perceived risks and benefits of vaccination and other key immunization beliefs. Frequencies of responses were stratified by type of provider, identified by exempt versus vaccinated children. Logistic regression was used to calculate odds ratios for responses by provider type. RESULTS: 551 surveys were completed (84.3% response rate). Providers for exempt children had similar attitudes to providers for non-exempt children. However, there were statistically significant increased concerns among providers for exempt children regarding vaccine safety and lack of perceived individual and community benefits for vaccines compared to other providers. CONCLUSIONS: The great majority of providers for exempt children had similar attitudes about vaccine safety, effectiveness and benefits as providers of non-exempt children. Although providers for exempt children were more likely to believe that multiple vaccines weaken a child's immune system and were concerned about vaccine safety and less likely to consider vaccines were beneficial, a substantial proportion of providers of both exempt and vaccinated children have concerns about vaccine safety and believe that CDC underestimates the frequency of vaccine side effects. Effective continuing education of providers about the risks and benefits of immunization and including in vaccine recommendations more information on pre and post licensing vaccine safety evaluations may help address these concerns.

Project protect: pneumococcal vaccination in Washington State nursing homes.

BACKGROUND: Pneumonia is the third most frequent cause of hospitalization among Medicare beneficiaries in Washington State. While a vaccine against pneumococcal disease has been available since 1977, the 1999 Behavioral Risk Factor Surveillance System estimates that less than 60% of adults aged 65 years and older in Washington State have been vaccinated. METHODS: To assess the prevalence of pneumococcal vaccination policies, we surveyed all Washington nursing homes in 1999 and again in 2001 to assess changes during the intervening period. Following the policy surveys, to estimate the pneumococcal vaccination rate, we conducted assessments of a random sample of residents of Washington nursing homes. RESULTS: Use of standing orders/written pneumococcal vaccination policies by nursing homes increased by 14% from 58% in 1999 to 72% in 2001. The pneumococcal vaccination rate for residents of nursing homes increased from 47% in 2000 to 61% in 2002. Both increases were statistically significant. The odds of a resident receiving a pneumococcal polysaccharide vaccine (PPV) in a nursing home having standing orders or other written guidelines are estimated to be two-and-a-half times greater than for residents in facilities without any PPV guidelines (2000: OR = 2.59; 95% CI, 1.54-4.34; 2002: OR = 3.19; 95% CI, 1.68-6.01). CONCLUSION: Increased use of standing orders/written policies has contributed to higher rates of pneumococcal vaccination in Washington State nursing homes.

Factors associated with refusal of childhood vaccines among parents of school-aged children: a case-control study.

BACKGROUND: The rate of nonmedical exemptions to school immunization requirements has been increasing, and children with exemptions have contributed to outbreaks of vaccine-preventable diseases. OBJECTIVES: To determine why parents claim nonmedical exemptions and to explore differences in perceptions of vaccines and vaccine information sources between parents of exempt and fully vaccinated children. DESIGN: Case-control study. SETTING: Colorado, Massachusetts, Missouri, and Washington. PARTICIPANTS: Surveys were mailed to the parents of 815 exempt children (cases) and 1630 fully vaccinated children (controls randomly selected from the same grade and school) recruited from 112 private and public elementary schools. Surveys were completed by 2435 parents (56.1%). MAIN OUTCOME MEASURES: Parental reports. RESULTS: Most children (209 [75.5%] of 277) with nonmedical exemptions received at least some vaccines. The most common vaccine not received was varicella (147 [53.1%] of 277 exempt children). The most common reason stated for requesting exemptions (190 [69%] of 277) was concern that the vaccines might cause harm. Parents of exempt children were significantly more likely than parents of vaccinated children to report low perceived vaccine safety and efficacy, a low level of trust in the government, and low perceived susceptibility to and severity of vaccine-preventable diseases. Parents of exempt children were significantly less likely to report confidence in medical, public health, and government sources for vaccine information and were more likely to report confidence in alternative medicine professionals than parents of vaccinated children. CONCLUSION: Continued efforts must be made to educate parents about the utility and safety of vaccines, especially parents requesting nonmedical exemptions to school immunization requirements.

Exemptions to school immunization requirements: the role of school-level requirements, policies, and procedures.

OBJECTIVES: Our goal was to determine whether school-level variability in implementation of immunization requirements is associated with the likelihood of a child having received an exemption to school immunization requirements. METHODS: We surveyed 1000 school immunization personnel in Colorado, Massachusetts, Missouri, and Washington. We explored associations between school implementation of immunization requirements and the likelihood of a child having an exemption using logistic regression models. RESULTS: School policies associated with an increased likelihood of children having exemptions included lack of provision of written instructions for completing the school immunization requirement before enrollment, administrative procedures making it easier to claim an exemption, and granting of philosophical exemptions. In the 2 states we surveyed where philosophical exemptions are not authorized (Massachusetts and Missouri), 17.0% and 18.1% of schools reported permitting philosophical exemptions. CONCLUSIONS: Inconsistencies in the interpretation and implementation of school immunization laws contribute to variability in rates of exemptions. School policies should be reviewed to ensure consistency with the intent of state laws.

Childhood immunization registries: gaps between knowledge and action among family practice physicians and pediatricians in Washington state, 1998.

OBJECTIVES: To assess the availability and use of Washington State's CHILD (Children's Health, Immunization, Linkages, and Development) Profile and other computerized immunization tracking systems, to determine physicians' attitudes about these systems, and to identify factors associated with using them. DESIGN: Randomized, population-based, cross-sectional survey. PARTICIPANTS: Washington family physician and pediatrician specialty organization members providing childhood immunizations in 1998 (N = 2472). MAIN OUTCOME MEASURE: Reported CHILD Profile and other computerized systems use. RESULTS: The adjusted response rate was 75% (n = 1331). Overall, 37.7% of respondents had heard of CHILD Profile, 6.3% used it, and 24.9% used other systems. Groups significantly more likely not to use computerized systems than referent pediatricians in areas fully implementing CHILD Profile were family physicians (adjusted odds ratio [aOR], 2.4; 95% confidence interval [CI], 1.4-4.0), private physicians (aOR, 8.0; 95% CI, 3.2-20.1), physicians taking fewest opportunities to immunize (aOR, 2.3; 95% CI, 1.4-3.7), and physicians practicing in local health jurisdiction areas with CHILD Profile marketing activity (aOR, 2.1; 95% CI, 1.2-3.9) or in those areas with little or no registry activity (aOR, 2.6; 95% CI, 1.6-4.4). Those with systems agreed that they save time (71.0%), make status checks easier (87.1%), and increase immunization coverage (88.6%). Those without systems agreed that they help practices (90.3%) and increase efficiency (76.5%), but fewer agreed that they reduce costs (30.2%). CONCLUSIONS: Although most physicians agreed that computerized systems are useful, few had them or used them. Provider-based systems can improve immunization coverage, but the feasibility and effectiveness of communitywide and statewide systems remain unexplored. Because these systems depend on participation, more understanding is needed to help organizations implement them. Interventions to increase availability and use should address provider and health organization needs.