James A. Singleton

National, Regional, State, and Selected Local Area Vaccination Coverage Among Adolescents Aged 13-17 Years — United States, 2014

The Advisory Committee on Immunization Practices (ACIP) recommends that adolescents aged 11-12 years routinely receive vaccines to prevent diseases, including human papillomavirus (HPV)-associated cancers, pertussis, and meningococcal disease (1). To assess vaccination coverage among adolescents in the United States, CDC analyzed data collected regarding 21,875 adolescents through the 2015 National Immunization Survey-Teen (NIS-Teen).* During 2014-2015, coverage among adolescents aged 13-17 years increased for each HPV vaccine dose among males, including ≥1 HPV vaccine dose (from 41.7% to 49.8%), and increased modestly for ≥1 HPV vaccine dose among females (from 60.0% to 62.8%) and ≥1 quadrivalent meningococcal conjugate vaccine (MenACWY) dose (from 79.3% to 81.3%). Coverage with ≥1 HPV vaccine dose was higher among adolescents living in households below the poverty level, compared with adolescents in households at or above the poverty level.(†) HPV vaccination coverage (≥1, ≥2, or ≥3 doses) increased in 28 states/local areas among males and in seven states among females. Despite limited progress, HPV vaccination coverage remained lower than MenACWY and tetanus, diphtheria, and acellular pertussis vaccine (Tdap) coverage, indicating continued missed opportunities for HPV-associated cancer prevention.

The Influence of Chronic Illnesses on the Incidence of Invasive Pneumococcal Disease in Adults

Pneumococcal disease is more frequent and more deadly in persons with certain comorbidities. We used 1999 and 2000 data from the Active Bacterial Core surveillance (ABCs) and the National Health Interview Survey (NHIS) to determine rates of invasive pneumococcal disease in healthy adults (> or =18 years old) and in adults with various high-risk conditions. The risks of invasive pneumococcal disease in persons with specific chronic illnesses was compared with that in healthy adults, controlling for age, race, and the other chronic illnesses. Overall incidence rates, in cases/100,000 persons, were 8.8 in healthy adults, 51.4 in adults with diabetes, 62.9 in adults with chronic lung disease, 93.7 in adults with chronic heart disease, and 100.4 in adults who abused alcohol. Among the high-risk groups evaluated, risk was highest in adults with solid cancer (300.4), HIV/AIDS (422.9), and hematological cancer (503.1). Incidence rates increased with advancing age in adults with chronic lung disease, diabetes, and solid cancer. Black adults had higher incidence rates than white adults, both in healthy adults and in adults with chronic illnesses. These data support recommendations to provide pneumococcal vaccine to persons in these at-risk groups and underscore the need for better prevention strategies for immunocompromised persons.

An overview of the vaccine adverse event reporting system (VAERS) as a surveillance system

We evaluated the Vaccine Adverse Event Reporting System (VAERS), the spontaneous reporting system for vaccine-associated adverse events in the United States, as a public health surveillance system, using evaluation guidelines from the Centers for Disease Control and Prevention. We found that VAERS is simple for reporters to use, flexible by design and its data are available in a timely fashion. The predictive value positive for one severe event is known to be high, but for most events is unknown. The acceptability, sensitivity and representativeness of VAERS are unknown. The study of vaccine safety is complicated by underreporting, erroneous reporting, frequent multiple exposures and multiple outcomes.

Influenza Vaccination of Healthcare Workers in the United States, 1989-2002

OBJECTIVES We sought to estimate influenza vaccination coverage among healthcare workers (HCWs) in the United States during 1989-2002 and to identify factors associated with vaccination in this group. The Advisory Committee on Immunization Practices (ACIP) recommends annual influenza vaccination for HCWs to reduce transmission of influenza to patients at high risk for serious complications of influenza. DESIGN Analysis of cross-sectional data from 1989-2002 surveys conducted by the National Health Interview Survey (NHIS). The outcome measure was self-reported influenza vaccination in the past 12 months. Bivariate and multivariate analysis of 2002 NHIS data. SETTING Household interviews conducted during 1989-2002, weighted to reflect the noninstitutionalized, civilian US population. PARTICIPANTS Adults aged 18 years or older participated in the study. A total of 2,089 were employed in healthcare occupations or settings in 2002, and 17,160 were employed in nonhealthcare occupations or settings. RESULTS The influenza vaccination rate among US HCWs increased from 10.0% in 1989 to 38.4% in 2002, with no significant change since 1997. In a multivariate model that included data from the 2002 NHIS, factors associated with a higher rate of influenza vaccination among HCWs aged 18-64 years included age of 50 years or older (odds ratio [OR], 1.6; 95% confidence interval [CI], 1.1-2.1), hospital employee status (OR, 1.5; 95% CI, 1.2-1.9), 1 or more visits to the office of a healthcare professional in the past 12 months (OR, 1.5; 95% CI, 1.1-2.2), receipt of employer-provided health insurance (OR, 1.5; 95% CI, 1.1-2.1), a history of pneumococcal vaccination (OR, 3.9; 95% CI, 2.5-6.1), and history of hepatitis B vaccination (OR, 1.9; 95% CI, 1.4-2.4). Non-Hispanic black persons were less likely to be vaccinated (OR, 0.6; 95% CI, 0.5-0.9) than non-Hispanic white persons. There were no significant differences in vaccination levels according to HCW occupation category. CONCLUSIONS Influenza immunization among HCWs reached a plateau during 1997-2002. New strategies are needed to encourage US HCWs to receive influenza vaccination to prevent influenza illness in themselves and transmission of influenza to vulnerable patients.

Influenza Illness and Hospitalizations Averted by Influenza Vaccination in the United States, 2005-2011

Context The goal of influenza vaccination programs is to reduce influenza-associated disease outcomes. Therefore, estimating the reduced burden of influenza as a result of vaccination over time and by age group would allow for a clear understanding of the value of influenza vaccines in the US, and of areas where improvements could lead to greatest benefits. Objective To estimate the direct effect of influenza vaccination in the US in terms of averted number of cases, medically-attended cases, and hospitalizations over six recent influenza seasons. Design Using existing surveillance data, we present a method for assessing the impact of influenza vaccination where impact is defined as either the number of averted outcomes or as the prevented disease fraction (the number of cases estimated to have been averted relative to the number of cases that would have occurred in the absence of vaccination). Results We estimated that during our 6-year study period, the number of influenza illnesses averted by vaccination ranged from a low of approximately 1.1 million (95% confidence interval (CI) 0.6–1.7 million) during the 2006–2007 season to a high of 5 million (CI 2.9–8.6 million) during the 2010–2011 season while the number of averted hospitalizations ranged from a low of 7,700 (CI 3,700–14,100) in 2009–2010 to a high of 40,400 (CI 20,800–73,000) in 2010–2011. Prevented fractions varied across age groups and over time. The highest prevented fraction in the study period was observed in 2010–2011, reflecting the post-pandemic expansion of vaccination coverage. Conclusions Influenza vaccination programs in the US produce a substantial health benefit in terms of averted cases, clinic visits and hospitalizations. Our results underscore the potential for additional disease prevention through increased vaccination coverage, particularly among nonelderly adults, and increased vaccine effectiveness, particularly among the elderly.

Vaccination and Perinatal Infection Prevention Practices Among Obstetrician-Gynecologists

OBJECTIVE To assist efforts to improve adult vaccination coverage by characterizing vaccination and infectious disease screening practices of obstetrician–gynecologists. METHODS A written survey of demographics, attitudes, and practices was mailed to 1063 American College of Obstetricians and Gynecologists Fellows, including the Collaborative Ambulatory Research Network (n = 413) and 650 randomly sampled Fellows. RESULTS Seventy-four percent of Collaborative Ambulatory Research Network members and 44% of nonmembers responded. A majority (Collaborative Ambulatory Research Network members: 60%; nonmembers: 49%) considered themselves primary care providers. Fewer than 60% routinely obtained patient vaccination or infection histories. Most screened prenatal patients for hepatitis B surface antigen (89%) and rubella immunoglobulin G antibody (85%). Sixty-four percent worked in practices that offered at least one vaccine; the most common were rubella (52%) and influenza (50%). Ten percent worked in practices that offered all major vaccines recommended for pregnant or postpartum women. Despite recommendations to provide influenza vaccine to pregnant women during influenza season, only 44% did so; among those who did not, 14% reported a belief that pregnant women do not need influenza vaccine. Provision of vaccine was associated with working in a multispecialty practice (adjusted odds ratio [OR] 2.6, 95% confidence interval [CI] 1.6, 4.1) and identifying as a primary care provider (adjusted OR 1.9; 95% CI 1.3, 2.7). The most common reasons for not offering vaccines were cost (44%) and a belief that vaccines should be provided elsewhere (41%). CONCLUSION The high proportion of obstetrician–gynecologists who do not offer vaccines or screen for vaccine and infection histories suggests missed opportunities for prevention of maternal and neonatal infections.

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.

Effects of Vaccine Program against Pandemic Influenza A(H1N1) Virus, United States, 2009–2010

Vaccination likely prevented 700,000–1,500,000 clinical cases, 4,000–10,000 hospitalizations, and 200–500 deaths.

Seasonal Influenza Vaccination Coverage Among Adult Populations in the United States, 2005–2011

The most effective strategy for preventing influenza is annual vaccination. We analyzed 2005-2011 data from the National Health Interview Survey (NHIS), using Kaplan-Meier survival analysis to estimate cumulative proportions of persons reporting influenza vaccination in the 2004-2005 through 2010-2011 seasons for persons aged ≥18, 18-49, 50-64, and ≥65 years, persons with high-risk conditions, and health-care personnel. We compared vaccination coverage by race/ethnicity within each age and high-risk group. Vaccination coverage among adults aged ≥18 years increased from 27.4% during the 2005-2006 influenza season to 38.1% during the 2010-2011 season, with an average increase of 2.2% annually. From the 2005-2006 season to the 2010-2011 season, coverage increased by 10-12 percentage points for all groups except adults aged ≥65 years. Coverage for the 2010-2011 season was 70.2% for adults aged ≥65 years, 43.7% for adults aged 50-64 years, 36.7% for persons aged 18-49 years with high-risk conditions, and 55.8% for health-care personnel. In most subgroups, coverage during the 2010-2011 season was significantly lower among non-Hispanic blacks and Hispanics than among non-Hispanic whites. Vaccination coverage among adults under age 65 years increased from 2005-2006 through 2010-2011, but substantial racial/ethnic disparities remained in most age groups. Targeted efforts are needed to improve influenza vaccination coverage and reduce disparities.

Effect of Vaccine Shortages on Timeliness of Pneumococcal Conjugate Vaccination: Results From the 2001–2005 National Immunization Survey

BACKGROUND. In September 2001 and again in February 2004, the Centers for Disease Control and Prevention announced shortages in the supply of the pneumococcal conjugate vaccine. We describe the effects of the pneumococcal conjugate vaccine shortages in 2001–2003 and 2004 on the timeliness of vaccination uptake for quarterly birth cohorts affected by the shortages. METHODS. A total of 102478 19- to 35-month-old children were sampled by the National Immunization Survey between 2001 and 2005. Provider-reported vaccination histories were used to evaluate whether children had been administered ≥4 doses of pneumococcal conjugate vaccine by 16 months of age. RESULTS. Among successive birth cohorts affected by the first shortage, estimated coverage of ≥4 doses of pneumococcal conjugate vaccine by 16 months declined significantly from 28.8% to 18.2%. As the first shortage ended, estimated coverage of ≥4 doses of pneumococcal conjugate vaccine by 16 months increased steadily with each successive birth cohort to 40.2%. From the onset of the second shortage, estimated coverage of ≥4 doses of pneumococcal conjugate vaccine by 16 months declined steadily and significantly to 13.7%. As many as 27% of parents whose child was affected by the first shortage reported that their childs vaccination provider had delayed the administration of pneumococcal conjugate vaccine doses. Of those parents who said that a pneumococcal conjugate vaccine dose was delayed and whose child was not administered ≥4 doses, 2.9% received a reminder notice from the provider to schedule administration of those delayed doses, and 0.2% had an appointment to receive those delayed or missed doses. CONCLUSIONS. Vaccine shortages can result in delayed or missed doses and can have a dramatic impact on the vaccine coverage of children. Vaccination providers need to communicate effectively with parents so that doses that are delayed or missed during a vaccine shortage are administered when the shortage is resolved.