Exploring the choice to refuse or delay vaccines: a national survey of parents of 6- through 23-month-olds.

OBJECTIVE: The purpose of this study was to assess respondents' self-reported choices for vaccinating their young children; knowledge, attitudes, and beliefs (KABs) about vaccination; and communication with their child's vaccination provider. METHODS: A national telephone survey of 1500 parents of children aged 6 to 23 months was conducted in 2010. We calculated proportions of parents who had chosen-or planned-to refuse or delay 1 or more recommended vaccines, and proportions for responses to KABs and communication questions, stratified by vaccination choice (ie, refuse or delay). RESULTS: The response rate was 46%. Among the 96.6% of respondents (95% confidence interval [CI], 95.5%-97.4%; weighted n = 1453) who had chosen for their child to receive at least 1 vaccine, 80.6% (95% CI, 78.8%-83.0%) reported that their child had received all vaccines when recommended and 86.5% (95% CI, 84.7%-88.2%) reported that their child would receive remaining vaccines when recommended. Respondents who considered not following recommendations, but ultimately did, cited the physician's recommendation as the reason for vaccinating. Most vaccinators who reported past or planned deviations from recommendations cited only 1 vaccine that they would refuse and/or delay; all vaccines were mentioned. These parents reported approaching vaccination with serious concerns, while believing other parents did not. All parents cited "vaccine side effects" as their top question or concern. Almost all parents talked to a doctor or nurse about vaccines and, overall, satisfaction with communication was high. CONCLUSIONS: Communication about vaccines is important to most parents, but may be challenging for providers, because parental choices vary; thus, efforts to improve and support vaccine communication by providers should continue.

Racial inequities in receipt of influenza vaccination among nursing home residents in the United States, 2008-2009: a pattern of low overall coverage in facilities in which most residents are black.

OBJECTIVES: Nationwide among nursing home residents, receipt of the influenza vaccine is 8 to 9 percentage points lower among blacks than among whites. The objective of this study was to determine if the national inequity in vaccination is because of the characteristics of facilities and/or residents. DESIGN: Cross-sectional study with multilevel modeling. SETTING AND PARTICIPANTS: States in which 1% or more of nursing home residents were black and the difference in influenza vaccination coverage between white and black nursing home residents was 1 percentage point or higher (n = 39 states and the District of Columbia). Data on residents (n = 2,359,321) were obtained from the Centers for Medicare & Medicaid Service's Minimum Data Set for October 1, 2008, through March 31, 2009. MEASUREMENTS: Residents' influenza vaccination status (vaccinated, refused vaccine, or not offered vaccination). RESULTS: States with higher overall influenza vaccination coverage among nursing home residents had smaller racial inequities. In nursing homes with higher proportions of black residents, vaccination coverage was lower for both blacks and whites. The most dramatic inequities existed between whites in nursing homes with 0% blacks (L1) and blacks in nursing homes with 50% or more blacks (L5) in states with overall racial inequities of 10 percentage points or more. In these states, more black nursing home residents lived in nursing homes with 50% or more blacks (L5); in general, the same homes with low overall coverage. CONCLUSION: Inequities in influenza vaccination coverage among nursing home residents are largely because of low vaccination coverage in nursing homes with a high proportion of black residents. Findings indicate that implementation of culturally appropriate interventions to increase vaccination in facilities with larger proportions of black residents may reduce the racial gap in influenza vaccination as well as increase overall state-level vaccination.

Timely identification of optimal control strategies for emerging infectious diseases.

BACKGROUND: Health authorities must rely on quarantine, isolation, and other non-pharmaceutical interventions to contain outbreaks of newly emerging human diseases. METHODS: We modeled a generic disease caused by a pathogen apparently transmitted by close interpersonal contact, but about which little else is known. In our model, people may be infectious while incubating or during their prodrome or acute illness. We derived an expression for Re, the reproduction number, took its partial derivatives with respect to control parameters, and encoded these analytical results in a user-friendly Mathematica notebook. With biological parameters for SARS estimated from the initial case series in Hong Kong and infection rates from hospitalizations in Singapore, we determined Re's sensitivity to control parameters. RESULTS: Stage-specific infection rate estimates from cases hospitalized before quarantine began exceed those from the entire outbreak, but are qualitatively similar: infectiousness was negligible until symptom onset, and increased 10-fold from prodrome to acute illness. Given such information, authorities might instead have emphasized a strategy whose efficiency more than compensates for any possible reduction in efficacy. CONCLUSIONS: In future outbreaks of new human diseases transmitted via close interpersonal contact, it should be possible to identify the optimal intervention early enough to facilitate effective decision-making.

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.

PURPOSE: To present progress toward Healthy People 2010 vaccination objectives for adolescents aged 13-15 years, and to determine how much catch-up and routine vaccination was administered at the recommended ages of 11-12 years. METHODS: Data from the 1997-2003 National Health Interview Survey were evaluated. In the first analysis, vaccination coverage levels for adolescents aged 13-15 years were determined for each survey year. Main outcome measures include the percent of adolescents who had received the three-dose hepatitis B vaccine (Hep B) series, the two-dose measles/mumps/rubella vaccine (MMR) series, the tetanus and diphtheria toxoids (Td) booster, and one dose of varicella vaccine. In the second analysis, data from all survey years were combined and vaccination dates were analyzed to determine the percentage of adolescents who were missing any vaccines at ages 11-12 and received them at that age. Data for varicella vaccine were sufficient only for the first analysis. RESULTS: Among the approximately 15%-20% of respondents who reported vaccination history from records in the home and who were reporting on a 13-15-year-old, coverage with three doses of Hep B increased significantly during 1997-2001, from 15.2% to 55.0%. Coverage with MMR and Td fluctuated, with no significant increase; highs were 76.7% for MMR in 2003 and 36.2% for Td in 2002. Examination of vaccination dates for all surveyed adolescents showed that among 11-12-year-olds who needed catch-up vaccine, 0.6%-31.3% were brought up to date for Hep B and 22.1%-31.8% were brought up to date for MMR. For Td, 2.6%-15.4% of 11-12-year-olds who had not previously received Td received the vaccine. CONCLUSION: Vaccination coverage among adolescents aged 13-15 years was below the Healthy People 2010 goals of 90%, but generally increased over the survey years. However, the suboptimal delivery of needed vaccines during ages 11 and 12 is concerning in light of recent vaccine recommendations targeted at this age. Continuing to focus on strategies to make adolescent preventive care, including vaccination, a new norm is essential.

Vaccination coverage in the US Commonwealth of the Northern Mariana Islands, 2005.

BACKGROUND: In July 2005, a house-to-house survey was conducted to determine vaccination coverage achieved through routine health services on the three inhabited islands (Saipan, Rota, and Tinian) of the US Commonwealth of the Northern Mariana Islands (CNMI). METHODS: A population-based cluster survey was conducted on Saipan; clusters and households were selected by systematic random sampling. On the smaller islands of Rota and Tinian, all households were visited. Vaccination histories and demographic information were obtained during household interview for all children aged 19-35 months, children aged 6 years, and adults aged 65 years and older. Vaccination histories for children were supplemented by hospital/clinic records and an electronic vaccination registry. RESULTS: Among 295 children aged 19-35 months, estimated coverage with the primary vaccination series was 80 percent; coverage with individual vaccines was generally higher. Among 193 children aged 6 years, coverage for vaccines required at school-aged was 83 percent. Among 226 adults aged 65 years and older, 52 percent received influenza vaccine during the previous season while 21 percent had ever received pneumococcal vaccine. CONCLUSIONS: The CNMI has achieved the US Healthy People 2010 objective of 80 percent coverage for the standard vaccination series among children aged 19-35 months. High coverage levels among 6-year-old children may reflect the benefit of school entry requirements. Influenza and pneumococcal vaccination among older adults remains low. Efforts to ensure that children and older adults throughout the CNMI are equally well-protected should continue. Strategies to address parental awareness of vaccinations that are due should be explored and may be facilitated by upgrading the electronic vaccination registry.

Timeliness of childhood immunizations: a state-specific analysis.

OBJECTIVE: We examined the timeliness of vaccine administration among children aged 24 to 35 months for each state of the United States and the District of Columbia. METHODS: We analyzed the timeliness of vaccinations in the 2000-2002 National Immunization Survey. We used a modified Bonferroni adjustment to compare a reference state with all other states. RESULTS: Receipt of all vaccinations as recommended ranged from 2% (Mississippi) to 26% (Massachusetts), with western states having less timeliness than eastern states. CONCLUSIONS: Vaccination coverage measures usually focus on the number of vaccinations accumulated by specified ages. Our analysis of timeliness of administration shows that children rarely receive all vaccinations as recommended. State health departments can use timeliness of vaccinations along with other measures to determine children's susceptibility to vaccine-preventable diseases and to evaluate the quality of vaccination programs. States can use the modified Bonferroni comparison to appropriately compare their results with other states.

Timeliness of childhood vaccinations in the United States: days undervaccinated and number of vaccines delayed.

CONTEXT: Only 18% of children in the United States receive all vaccinations at the recommended times or acceptably early. OBJECTIVE: To determine the extent of delay of vaccination during the first 24 months of life. DESIGN, SETTING, AND PARTICIPANTS: The 2003 National Immunization Survey was conducted by random-digit dialing of households and mailings to vaccination providers to estimate vaccination coverage rates for US children aged 19 to 35 months. Data for this study were limited to 14,810 children aged 24 to 35 months. MAIN OUTCOME MEASURES: Cumulative days undervaccinated during the first 24 months of life for each of 6 vaccines (diphtheria and tetanus toxoids and acellular pertussis; poliovirus; measles, mumps, and rubella; Haemophilus influenzae type b; hepatitis B; and varicella) and all vaccines combined, number of late vaccines, and risk factors for severe delay of vaccination. RESULTS: Children were undervaccinated a mean of 172 days (median, 126 days) for all vaccines combined during their first 24 months of life. Approximately 34% were undervaccinated for less than 1 month and 29% for 1 to 6 months, while 37% were undervaccinated for more than 6 months. Vaccine-specific undervaccination of more than 6 months ranged from 9% for poliovirus vaccine to 21% for Haemophilus influenzae type b vaccine. An estimated 25% of children had delays in receipt of 4 or more of the 6 vaccines. Approximately 21% of children were severely delayed (undervaccinated for more than 6 months and for > or vaccines). Factors associated with severe delay included having a mother who was unmarried or who did not have a college degree, living in a household with 2 or more children, being non-Hispanic black, having 2 or more vaccination providers, and using public vaccination provider(s). CONCLUSIONS: More than 1 in 3 children were undervaccinated for more than 6 months during their first 24 months of life and 1 in 4 children were delayed for at least 4 vaccines. Standard measures of vaccination coverage mask substantial shortfalls in ensuring that recommendations are followed regarding age at vaccination throughout the first 24 months of life.

Maternal characteristics associated with vaccination of young children.

OBJECTIVE: Mothers can be instrumental in gaining access to vaccination services for their children. This study examines maternal characteristics associated with vaccination in US preschool children. METHODS: We analyzed data from 21 212 children aged 19 to 35 months in the National Immunization Survey. Bivariate and multivariate analyses were used to identify maternal characteristics associated with completion of all recommended vaccinations in these children. RESULTS: Factors most strongly associated with undervaccination included having mothers who were black; had less than a high school education; were divorced, separated, or widowed; had multiple children; were eligible for the Special Supplemental Nutrition Program for Women, Infants and Children (WIC) but not participating; or had incomes below 50% of the federal poverty level. CONCLUSION: Because most mothers play an important role in their children's vaccination, it is important to address maternal concerns and barriers when developing public health interventions for promoting childhood vaccinations. Encouraging eligible women and their children to participate in the WIC program and providing support and encouragement for immunization to mothers with multiple children may improve early childhood vaccination coverage.

Timeliness of childhood immunizations.

OBJECTIVE: To examine the timeliness of vaccine administration among infants and young children in the United States. METHODS: We analyzed age at receipt of vaccines among 16 211 children aged 24 to 35 months in the 2000 National Immunization Survey and examined receipt at the recommended time of each dose and selected vaccination series, as well as receipt at 4 additional time frames: acceptably early, late, never by 24 months, and too early to be considered valid. We also examined the relationship between timeliness of vaccinations and characteristics of the child, mother, and immunization provider, using multivariate logistic regression. RESULTS: Only 9% of children received all recommended vaccines at the recommended ages. The rates varied significantly by antigen, ranging from 24% for all Haemophilus influenzae type b doses to 75% for all hepatitis B doses as recommended. Overall, 55% of children did not receive all recommended doses by 24 months of age, and 8% of children received at least 1 vaccination dose too early to be considered valid. Factors associated with not receiving all vaccines as recommended were having more children in the household, mothers younger than 30 years, use of public providers, and multiple vaccination providers. CONCLUSIONS: By 24 months of age, 9 of 10 children received at least 1 vaccine outside the recommended age ranges. High vaccination status of children at 24 months of age does not reflect the reality that many vaccinations are not given at the appropriate ages. Timeliness of vaccination is critical to prevent disease outbreaks, protect children through their first 2 years of life, and minimize the need to repeat doses.

The changing epidemiology of rubella in the 1990s: on the verge of elimination and new challenges for control and prevention.

CONTEXT: In 1989, the United States established a goal to eliminate indigenous rubella and congenital rubella syndrome (CRS) by 2000. Reported rubella cases are at record low levels; however, cases and outbreaks have occurred, primarily among unvaccinated foreign-born adults. OBJECTIVE: To evaluate the current epidemiology of rubella and CRS and assess progress toward elimination. DESIGN, SETTING, AND SUBJECTS: Analysis of rubella cases reported to the National Notifiable Diseases Surveillance System from 1990 through 1999 and CRS cases reported to the National Congenital Rubella Syndrome Registry from 1990 through 1999. Since 1996, US and international viral isolates have been sequenced. MAIN OUTCOME MEASURES: Incidence and characteristics of rubella and CRS cases; molecular typing of virus isolates. RESULTS: Annually from 1990 through 1999, the median number of reported rubella cases was 232 (range, 128-1412), and between 1992 and 1999, fewer than 300 rubella cases were reported annually, except in 1998. During the 1990s, the incidence of rubella in children younger than 15 years decreased (0.63 vs 0.06 per 100 000 in 1990 vs 1999), whereas the incidence in adults aged 15 to 44 years increased (0.13 vs 0.24 per 100 000). In 1992, incidence among Hispanics was 0.06 per 100 000 and increased to a high in 1998 of 0.97 per 100 000. From 1997 through 1999, 20 (83%) of 24 CRS infants were born to Hispanic mothers, and 21 (91%) of 23 CRS infants were born to foreign-born mothers. Molecular typing identified 3 statistically distinct genotypic groups. In group 1, the close relatedness of viruses suggests that a single imported source seeded an outbreak that did not spread beyond the Northeast. Similarly, within groups 2 and 3, relatedness of viruses obtained from clusters of cases suggests that single imported sources seeded each one. Diversity of viruses found in 1 state is consistent with the conclusion that several viruses were imported. Moreover, the similarity of viruses found across the country, combined with a lack of epidemiologic evidence of endemic transmission, support the conclusion that some viruses that are common abroad, particularly in Latin America and the Caribbean, were introduced into the United States on several separate occasions. CONCLUSIONS: The epidemiology of rubella and CRS has changed significantly in the last decade. These changes and molecular typing suggest that the United States is on the verge of elimination of the disease. To prevent future rubella outbreaks and CRS, current strategies must be enhanced and new strategies developed.