Seasonal influenza vaccination coverage among adult populations in the United States, 2005-2011

Antigenic drift and subtype interference shape A(H3N2) epidemic dynamics in the United States

Influenza viruses continually evolve new antigenic variants, through mutations in epitopes of their major surface proteins, hemagglutinin (HA) and neuraminidase (NA). Antigenic drift potentiates the reinfection of previously infected individuals, but the contribution of this process to variability in annual epidemics is not well understood. Here, we link influenza A(H3N2) virus evolution to regional epidemic dynamics in the United States during 1997-2019. We integrate phenotypic measures of HA antigenic drift and sequence-based measures of HA and NA fitness to infer antigenic and genetic distances between viruses circulating in successive seasons. We estimate the magnitude, severity, timing, transmission rate, age-specific patterns, and subtype dominance of each regional outbreak and find that genetic distance based on broad sets of epitope sites is the strongest evolutionary predictor of A(H3N2) virus epidemiology. Increased HA and NA epitope distance between seasons correlates with larger, more intense epidemics, higher transmission, greater A(H3N2) subtype dominance, and a greater proportion of cases in adults relative to children, consistent with increased population susceptibility. Based on random forest models, A(H1N1) incidence impacts A(H3N2) epidemics to a greater extent than viral evolution, suggesting that subtype interference is a major driver of influenza A virus infection ynamics, presumably via heterosubtypic cross-immunity.

Antigenic drift and subtype interference shape A(H3N2) epidemic dynamics in the United States

Influenza viruses continually evolve new antigenic variants, through mutations in epitopes of their major surface proteins, hemagglutinin (HA) and neuraminidase (NA). Antigenic drift potentiates the reinfection of previously infected individuals, but the contribution of this process to variability in annual epidemics is not well understood. Here we link influenza A(H3N2) virus evolution to regional epidemic dynamics in the United States during 1997-2019. We integrate phenotypic measures of HA antigenic drift and sequence-based measures of HA and NA fitness to infer antigenic and genetic distances between viruses circulating in successive seasons. We estimate the magnitude, severity, timing, transmission rate, age-specific patterns, and subtype dominance of each regional outbreak and find that genetic distance based on broad sets of epitope sites is the strongest evolutionary predictor of A(H3N2) virus epidemiology. Increased HA and NA epitope distance between seasons correlates with larger, more intense epidemics, higher transmission, greater A(H3N2) subtype dominance, and a greater proportion of cases in adults relative to children, consistent with increased population susceptibility. Based on random forest models, A(H1N1) incidence impacts A(H3N2) epidemics to a greater extent than viral evolution, suggesting that subtype interference is a major driver of influenza A virus infection dynamics, presumably via heterosubtypic cross-immunity.

Factors Associated With Non-vaccination for Influenza Among Patients With CKD: Findings From the Chronic Renal Insufficiency Cohort (CRIC) Study

RATIONALE & OBJECTIVE

Vaccination for influenza is strongly recommended for people with chronic kidney disease (CKD) due to their immunocompromised state. Identifying risk factors for not receiving an influenza vaccine (non-vaccination) could inform strategies for improving vaccine uptake in this high-risk population.

STUDY DESIGN

Longitudinal observational study.

SETTING & PARTICIPANTS

3,692 Chronic Renal Insufficiency Cohort Study (CRIC) participants.

EXPOSURE

Demographic factors, social determinants of health, clinical conditions, and health behaviors.

OUTCOME

Influenza non-vaccination, which was assessed based on a receipt of influenza vaccine ascertained during annual clinic visits in a subset of participants who were under nephrology care.

ANALYTICAL APPROACH

Mixed-effects Poisson models to estimate adjusted prevalence ratios (APRs).

RESULTS

Between 2009 and 2020, the pooled mean vaccine uptake was 72% (mean age, 66 years; 44% female; 44% Black race). In multivariable models, factors significantly associated with influenza non-vaccination were younger age (APR, 2.16 [95% CI, 1.85-2.52] for<50 vs≥75 years), Black race (APR, 1.58 [95% CI, 1.43-1.75] vs White race), lower education (APR, 1.20 [95% CI, 1.04-1.39 for less than high school vs college graduate]), lower annual household income (APR, 1.26 [95% CI, 1.06-1.49] for <$20,000 vs >$100,000), formerly married status (APR, 1.22 [95% CI, 1.09-1.35] vs currently married), and nonemployed status (APR, 1.13 [95% CI, 1.02-1.24] vs employed). In contrast, participants with diabetes (APR, 0.80 [95% CI, 0.73-0.87] vs no diabetes), chronic obstructive pulmonary disease (COPD) (APR, 0.80 [95% CI, 0.70-0.92] vs no COPD), end-stage kidney disease (APR, 0.64 [0.56 to 0.76] vs estimated glomerular filtration rate≥60mL/min/1.73m2), frailty (APR, 0.86 [95% CI, 0.74-0.99] vs no frailty), and ideal physical activity (APR, 0.90 [95% CI, 0.82-0.99] vs. physically inactive) were less likely to have non-vaccination status.

LIMITATIONS

Possible residual confounding.

CONCLUSIONS

Among adults with CKD receiving nephrology care, younger adults, Black individuals, and those with adverse social determinants of health were more likely to have the influenza non-vaccination status. Strategies are needed to address these disparities and reduce barriers to vaccination.

PLAIN-LANGUAGE SUMMARY

Identifying risk factors for not receiving an influenza vaccine ("non-vaccination") in people living with kidney disease, who are at risk of influenza and its complications, could inform strategies for improving vaccine uptake. In this study, we examined whether demographic factors, social determinants of health, and clinical conditions were linked to the status of not receiving an influenza vaccine among people living with kidney disease and receiving nephrology care. We found that younger adults, Black individuals, and those with adverse social determinants of health were more likely to not receive the influenza vaccine. These findings suggest the need for strategies to address these disparities and reduce barriers to vaccination in people living with kidney disease.

Impact of antiviral therapy on short- and long-term outcomes of patients with chronic obstructive pulmonary disease after influenza infection

Background

Respiratory complications often accompany influenza in patients with chronic obstructive pulmonary disease (COPD). In this retrospective study, we quantified the impact of antiviral therapy on exacerbations, healthcare resource utilization (HRU), and costs in patients with COPD across 5 influenza seasons.

Methods

Using claims data from US MarketScan® databases, we identified patients with COPD who had an influenza diagnosis during the 2012-2016 influenza seasons. Patients who received a neuraminidase inhibitor within 48 h of diagnosis (N = 4134) were identified and propensity score-matched 1:1 to a comparator cohort of untreated patients. We determined COPD- and pneumonia-related HRU and costs during month 1, each subsequent quarter, and months 2-13.

Results

Antiviral-treated patients had a significantly lower frequency of COPD-related outcomes than untreated patients during all periods (exacerbations: 10.4% vs 18.2% [month 1] and 17.7% vs 24.2% [months 2-13]; inpatient visit: 2.5% vs 7.9% [month 1] and 3.8% vs 6.7% [months 2-13]; P < 0.0001, all comparisons). Treated patients also had significantly lower outpatient and emergency department (ED) visits beyond month 1. Pneumonia-related inpatient, ED, and outpatient visits were significantly lower in antiviral-treated patients than in untreated patients over all periods (P < 0.0001, all comparisons). In all HRU categories, COPD- and pneumonia-related costs were significantly lower in treated patients over all periods (month-1 ED visit costs were higher).

Conclusions

Antiviral treatment in patients with COPD and influenza is associated with significantly lower HRU and costs in the postinfection month and for an entire year following infection compared with untreated patients.

Trends in influenza vaccine uptake before and during the COVID-19 pandemic in the USA

OBJECTIVES

To investigate trends of influenza vaccine uptake before and during the COVID-19 pandemic in the USA and explore the associated factors.

STUDY DESIGN

This was a cross-sectional study.

METHODS

Using self-reported data from the National Health Interview Survey during 2014-2021 (response rates ranging from 50.7 to 70.1%), we estimated influenza vaccine uptake. Log-binomial regression models were used to test uptake changes with adjustment for and stratification by demographic and health factors.

RESULTS

We included 58,249 children (mean age: 8.7 years; male: 51.1%) and 205,034 adults (mean age: 47.6 years; male: 48.2%). The prevalence ratio (PR) of uptake change comparing the intra- (2020-2021) to the pre-COVID-19 period (2014-2019) was 0.72 among children, with a 10.7% reduction. Uptake changes were found across subgroups, with higher reduction among those aged 0-2 years, non-Hispanic Black and Hispanic ethnicity, from South and West regions, and with lower household income. For adults, uptake increased before and during COVID-19 (PR = 1.15, 95% confidence interval [CI]: 1.12-1.18) but a 2.3% reduction was found among healthcare personnel (PR = 0.95, 95% CI: 0.90-0.997).

CONCLUSIONS

Influenza vaccination decreased during the COVID-19 pandemic among children and healthcare personnel. Structure inequality to influenza vaccination warrants measures to improve vaccine uptake among vulnerable groups.

Influenza vaccination coverage among persons ages six months and older in the Vaccine Safety Datalink in the 2017-18 through 2022-23 influenza seasons

BACKGROUND

In the United States, annual vaccination against seasonal influenza is recommended for all people ages ≥ 6 months. Vaccination coverage assessments can identify populations less protected from influenza morbidity and mortality and help to tailor vaccination efforts. Within the Vaccine Safety Datalink population ages ≥ 6 months, we report influenza vaccination coverage for the 2017-18 through 2022-23 seasons.

METHODS

Across eight health systems, we identified influenza vaccines administered from August 1 through March 31 for each season using electronic health records linked to immunization registries. Crude vaccination coverage was described for each season, overall and by self-reported sex; age group; self-reported race and ethnicity; and number of separate categories of diagnoses associated with increased risk of severe illness and complications from influenza (hereafter referred to as high-risk conditions). High-risk conditions were assessed using ICD-10-CM diagnosis codes assigned in the year preceding each influenza season.

RESULTS

Among individual cohorts of more than 12 million individuals each season, overall influenza vaccination coverage increased from 41.9 % in the 2017-18 season to a peak of 46.2 % in 2019-20, prior to declaration of the COVID-19 pandemic. Coverage declined over the next three seasons, coincident with widespread SARS-CoV-2 circulation, to a low of 40.3 % in the 2022-23 season. In each of the six seasons, coverage was lowest among males, 18-49-year-olds, non-Hispanic Black people, and those with no high-risk conditions. While decreases in coverage were present in all age groups, the declines were most substantial among children: 2022-23 season coverage for children ages six months through 8 years and 9-17 years was 24.5 % and 22.4 % (14 and 10 absolute percentage points), respectively, less than peak coverage achieved in the 2019-20 season.

CONCLUSIONS

Crude influenza vaccination coverage increased from 2017 to 18 through 2019-20, then decreased to the lowest level in the 2022-23 season. In this insured population, we identified persistent disparities in influenza vaccination coverage by sex, age, and race and ethnicity. The overall low coverage, disparities in coverage, and recent decreases in coverage are significant public health concerns.

Associations between Influenza Vaccination and Health Care Access among Adults in the United States

Few studies have investigated the relationship between influenza vaccination and health care access. Furthermore, despite the well-documented disparities in vaccine coverage for communities of color, few studies have examined how experiences of discrimination may influence vaccine uptake. To fill this gap in the literature, this study examined associations between 5-year influenza vaccination rates and sociodemographic characteristics, health care access, and racial discrimination. Age, race/ethnicity, education, health care coverage, primary care provider, no medical care due to cost, and routine doctor checkups were significant correlates of 5-year influenza vaccination. In contrast to previous studies, discrimination scores were not a significant correlate of regular influenza vaccination. Respondents who reported forgoing care due to cost were less likely to report vaccination every year out of the last 5 years compared to all of the less frequent categories combined, demonstrating a more complex association between sometimes not being able to afford medical care and influenza vaccination. Future research should examine the relationship between influenza vaccination uptake, racial discrimination, and forgone care due to cost to enhance resources and messaging for influenza vaccination uptake.

Associations between 5-year influenza vaccination and sociodemographic factors and healthcare access among Arkansans

Despite wide availability, only 50.2% of the United States (US) adult population and 50.3% of adult Arkansans were vaccinated for influenza during the 2020-2021 influenza season. The proportion of the population vaccinated for influenza varies by age, sex, race/ethnicity, education, rural/urban residence, and income. However, measures of healthcare access have not been adequately investigated as predictors of influenza vaccination. Using a large, statewide random sample, this study examined 5-year influenza vaccination among Arkansans by sociodemographic characteristics (age, sex, race/ethnicity, education, rural/urban residence), general vaccine hesitancy, and healthcare access (having a primary care provider, having health insurance, forgoing health care due to cost, and frequency of doctor checkups). Older age, being female, being Hispanic, having a bachelor's degree or higher, having a primary care provider, visiting a doctor for a checkup in the past two years, and lack of hesitancy towards vaccines were significant predictors of receiving influenza vaccination.

Factors associated with COVID-19 vaccine intent among Latino SNAP participants in Southern California

Background

COVID-19 is significantly impacting the health and well-being of the country, particularly for ethnic minority populations and low-income groups. Our goal was to determine COVID-19 vaccination intent in a low-income, Latino population receiving aid from the Supplemental Nutrition Assistance Program (SNAP) in Southern California, and identify contributing factors and concerns.

Methods

A cross-sectional, mixed-methods survey was conducted among participants in the Southern California Nutrition Incentives Program (¡Más Fresco! More Fresh). Only Latino respondents were included in this analysis. Primary outcome was vaccine intent trichotomized into: “definitely/likely yes”, “not sure/don’t know”, and “definitely/likely not.”

Results

The majority of participants (n = 486) were female (93%), Spanish speaking (74%), with a median age of 40 years (IQR = 13). Approximately half (48%) reported they would get a COVID-19 vaccine, 39% were unsure, and 13% reported “definitely/likely not”. In the multivariable multinomial logistic regression model, participants with a household member with a COVID-19 health risk factor were more likely to be unsure about getting the vaccine. Participants who were primarily English speaking, did not receive the influenza vaccine last season, and reported not reading or talking about COVID-19 were more likely to report not intending to receive the vaccine. Many respondents were concerned about “side effects and ingredients”, and did not trust the vaccine development process, particularly with how fast it happened.

Conclusion

Low-income Latinos in Southern California were generally hesitant to get a COVID-19 vaccine. Culturally sensitive vaccine promotion campaigns need to address the concerns of minority populations who experience increased morbidity and mortality from COVID-19.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12889-022-13027-w.

Factors Associated with Intention to Receive Vaccination against COVID-19 in Puerto Rico: An Online Survey of Adults

We conducted an online survey among adults in Puerto Rico to identify factors associated with the intention to receive vaccination against COVID-19. Sociodemographic variables were analyzed independently for association with intent to receive vaccination. Significant associations were included in the multivariate logistic regression analysis. A total of 1016 responses were available for analysis. In the bivariate analysis, younger age, higher education, pre-COVID-19 employment, male sex, gay/bisexual identity, and single marital status were associated with increased intent to receive the vaccination. In the multivariate logistic regression, younger, male respondents, and those with higher educational attainment reported higher intent to receive the vaccination. Lower-income and living outside the San Juan metro region were associated with lower intent to receive the vaccination. National and international health organizations were identified as the most reliable sources of information, followed by healthcare professionals. These findings highlight the importance of considering sociodemographic characteristics and using trusted sources of information when designing COVID-19 vaccination public messaging.

Surveillance of Vaccination Coverage Among Adult Populations -United States, 2018

PROBLEM/CONDITION

Adults are at risk for illness, hospitalization, disability and, in some cases, death from vaccine-preventable diseases, particularly influenza and pneumococcal disease. CDC recommends vaccinations for adults on the basis of age, health conditions, prior vaccinations, and other considerations. Updated vaccination recommendations from CDC are published annually in the U.S. Adult Immunization Schedule. Despite longstanding recommendations for use of many vaccines, vaccination coverage among U.S. adults remains low.

REPORTING PERIOD

August 2017-June 2018 (for influenza vaccination) and January-December 2018 (for pneumococcal, herpes zoster, tetanus and diphtheria [Td]/tetanus toxoid, reduced diphtheria toxoid, and acellular pertussis [Tdap], hepatitis A, hepatitis B, and human papillomavirus [HPV] vaccination).

DESCRIPTION OF SYSTEM

The National Health Interview Survey (NHIS) is a continuous, cross-sectional national household survey of the noninstitutionalized U.S. civilian population. In-person interviews are conducted throughout the year in a probability sample of households, and NHIS data are compiled and released annually. NHIS's objective is to monitor the health of the U.S. population and provide estimates of health indicators, health care use and access, and health-related behaviors. Adult receipt of influenza, pneumococcal, herpes zoster, Td/Tdap, hepatitis A, hepatitis B, and at least 1 dose of HPV vaccines was assessed. Estimates were derived for a new composite adult vaccination quality measure and by selected demographic and access-to-care characteristics (e.g., age, race/ethnicity, indication for vaccination, travel history [travel to countries where hepatitis infections are endemic], health insurance status, contacts with physicians, nativity, and citizenship). Trends in adult vaccination were assessed during 2010-2018.

RESULTS

Coverage for the adult age-appropriate composite measure was low in all age groups. Racial and ethnic differences in coverage persisted for all vaccinations, with lower coverage for most vaccinations among non-White compared with non-Hispanic White adults. Linear trend tests indicated coverage increased from 2010 to 2018 for most vaccines in this report. Few adults aged ≥19 years had received all age-appropriate vaccines, including influenza vaccination, regardless of whether inclusion of Tdap (13.5%) or inclusion of any tetanus toxoid-containing vaccine (20.2%) receipt was measured. Coverage among adults for influenza vaccination during the 2017-18 season (46.1%) was similar to the estimate for the 2016-17 season (45.4%), and coverage for pneumococcal (adults aged ≥65 years [69.0%]), herpes zoster (adults aged ≥50 years and aged ≥60 years [24.1% and 34.5%, respectively]), tetanus (adults aged ≥19 years [62.9%]), Tdap (adults aged ≥19 years [31.2%]), hepatitis A (adults aged ≥19 years [11.9%]), and HPV (females aged 19-26 years [52.8%]) vaccination in 2018 were similar to the estimates for 2017. Hepatitis B vaccination coverage among adults aged ≥19 years and health care personnel (HCP) aged ≥19 years increased 4.2 and 6.7 percentage points to 30.0% and 67.2%, respectively, from 2017. HPV vaccination coverage among males aged 19-26 years increased 5.2 percentage points to 26.3% from the 2017 estimate. Overall, HPV vaccination coverage among females aged 19-26 years did not increase, but coverage among Hispanic females aged 19-26 years increased 10.8 percentage points to 49.6% from the 2017 estimate. Coverage for the following vaccines was lower among adults without health insurance compared with those with health insurance: influenza vaccine (among adults aged ≥19 years, 19-49 years, and 50-64 years), pneumococcal vaccine (among adults aged 19-64 years at increased risk), Td vaccine (among all age groups), Tdap vaccine (among adults aged ≥19 years and 19-64 years), hepatitis A vaccine (among adults aged ≥19 years overall and among travelers aged ≥19 years), hepatitis B vaccine (among adults aged ≥19 years and 19-49 years and among travelers aged ≥19 years), herpes zoster vaccine (among adults aged ≥60 years), and HPV vaccine (among males and females aged 19-26 years). Adults who reported having a usual place for health care generally reported receipt of recommended vaccinations more often than those who did not have such a place, regardless of whether they had health insurance. Vaccination coverage was higher among adults reporting ≥1 physician contact during the preceding year compared with those who had not visited a physician during the preceding year, regardless of whether they had health insurance. Even among adults who had health insurance and ≥10 physician contacts during the preceding year, depending on the vaccine, 20.1%-87.5% reported not having received vaccinations that were recommended either for all persons or for those with specific indications. Overall, vaccination coverage among U.S.-born adults was significantly higher than that of foreign-born adults, including influenza vaccination (aged ≥19 years), pneumococcal vaccination (all ages), tetanus vaccination (all ages), Tdap vaccination (all ages), hepatitis B vaccination (aged ≥19 years and 19-49 years and travelers aged ≥19 years), herpes zoster vaccination (all ages), and HPV vaccination among females aged 19-26 years. Vaccination coverage also varied by citizenship status and years living in the United States.

INTERPRETATION

NHIS data indicate that many adults remain unprotected against vaccine-preventable diseases. Coverage for the adult age-appropriate composite measures was low in all age groups. Individual adult vaccination coverage remained low as well, but modest gains occurred in vaccination coverage for hepatitis B (among adults aged ≥19 years and HCP aged ≥19 years), and HPV (among males aged 19-26 years and Hispanic females aged 19-26 years). Coverage for other vaccines and groups with Advisory Committee on Immunization Practices vaccination indications did not improve from 2017. Although HPV vaccination coverage among males aged 19-26 years and Hispanic females aged 19-26 years increased, approximately 50% of females aged 19-26 years and 70% of males aged 19-26 years remained unvaccinated. Racial/ethnic vaccination differences persisted for routinely recommended adult vaccines. Having health insurance coverage, having a usual place for health care, and having ≥1 physician contacts during the preceding 12 months were associated with higher vaccination coverage; however, these factors alone were not associated with optimal adult vaccination coverage, and findings indicate missed opportunities to vaccinate remained.

PUBLIC HEALTH ACTIONS

Substantial improvement in adult vaccination uptake is needed to reduce the burden of vaccine-preventable diseases. Following the Standards for Adult Immunization Practice (https://www.cdc.gov/vaccines/hcp/adults/for-practice/standards/index.html), all providers should routinely assess adults' vaccination status at every clinical encounter, strongly recommend appropriate vaccines, either offer needed vaccines or refer their patients to another provider who can administer the needed vaccines, and document vaccinations received by their patients in an immunization information system.

Disparities in influenza vaccination: Arab Americans in California

Background

Influenza vaccination among minoritized groups remains below federal benchmarks in the United States (US). We used data from the 2004–2016 California Health Interview Surveys (CHIS) to characterize influenza vaccination patterns among Arab Americans in California.

Methods

Influenza vaccination was self-reported by Arab American adults (N = 1163) and non-Hispanic Whites (NHW, N = 166,955). Differences in influenza vaccination prevalence and odds were compared using chi-squared tests and survey-weighted logistic regression, respectively.

Results

Across all years, 30.3% of Arab Americans self-reported receiving an influenza vaccine (vs. 40.5% for NHW, p < 0.05). After sequential adjustment by sociodemographic, health behavior, and acculturation variables no differences in odds of self-reported influenza vaccination were observed between Arab Americans and NHW (odds ratio: 1.02, 95% confidence interval: 0.76–1.38). Male and unemployed Arab Americans had higher odds of reporting influenza vaccination than female and employed Arab Americans.

Conclusions

Future work should consider specific barriers to influenza vaccination in Arab American communities.

Influenza vaccination rates and location for receiving the influenza vaccination among older adult Medicare beneficiaries

OBJECTIVES

The objectives of this study were to (1) assess the trends in older adult influenza vaccination rates and (2) locations at which U.S. older adults received influenza vaccinations for the 2008-2009 to 2017-2018 influenza seasons, and (3) compare the estimates of influenza vaccination rates and locations with the estimates from other sources reported previously.

METHODS

Data from the 2009 to 2017 Medicare Current Beneficiary Survey (MCBS) were used in this analysis. The weighted sample included an average of approximately 37 million community-dwelling older Medicare beneficiaries who completed questionnaires per year. The estimates for older adult influenza vaccination rates and the locations that they used to receive the influenza vaccination were weighted and reported for the 2008-2009 to 2017-2018 influenza seasons.

RESULTS

The self-reported older adult influenza vaccination rates between 2008-09 and 2017-2018 ranged from 69.6% (24.6 million) to 75.0% (31.3 million). Across the study period, the percentage of older adults receiving the influenza vaccination at a physician office and clinic declined by 10.4%. The decline was more than offset by an increase in older adult influenza vaccination receipt at a community pharmacy, which substantially increased from 16.6% (4.1 million) in 2008-2009 to 34.8% (10.9 million) in 2014-2015. When compared with the estimates from other sources, the absolute value of the MCBS estimates corresponds with National Health Interview Survey estimates. The older adult influenza vaccination rate increased slightly between the 2008-2009 and 2017-2018 influenza seasons but is still below the 90% benchmark.

CONCLUSION

Community pharmacies-increasingly important access points for the influenza vaccination for older adults-likely contributed to the growth in the rate of older adults vaccinated with influenza vaccines.

Key policy and programmatic factors to improve influenza vaccination rates based on the experience from four high-performing countries

BACKGROUND

Many countries consistently fail to achieve the target influenza vaccine coverage rate (VCR) of 75% for populations at risk of complications, recommended by the World Health Organization and European Council. We aimed to identify factors for achieving a high VCR in the scope of four benchmark countries with high influenza VCRs: Australia, Canada, UK and USA.

METHODS

Publicly available evidence was first reviewed at a global level and then for each of the four countries. Semi-structured interviews were then conducted with stakeholders meeting predefined criteria. Descriptive cluster analyses were performed to identify key factors and pillars for establishing and maintaining high VCRs.

RESULTS

No single factor led to a high VCR, and each benchmark country used a different combination of tailored approaches to achieve a high vaccine coverage. In each country, specific triggers were important to stimulate changes that led to improved vaccine coverage. A total of 42 key factors for a successful influenza vaccination programme were identified and clustered into five pillars: (1) Health Authority accountability and strengths of the influenza programme, (2) facilitated access to vaccination, (3) healthcare professional accountability and engagement, (4) awareness of the burden and severity of disease and (5) belief in influenza vaccination benefit. Each benchmark country has implemented multiple factors from each pillar.

CONCLUSION

A wide range of factors were identified from an evaluation of four high-performing benchmark countries, classified into five pillars, thus providing a basis for countries with lower VCRs to tailor their own particular solutions to improve their influenza VCR.

Antiviral use is associated with a decrease in the rate of influenza-related complications, health care resource utilization, and costs

AIMS

To determine the effect of antiviral agents on influenza-related complications, health care resource utilization (HRU), and costs over three influenza seasons (2014-2016).

METHODS

This retrospective cohort study used claims data from the U.S. MarketScan Research Databases. Patients with a diagnosis code for influenza during the 2014-2016 seasons in an outpatient setting, with continuous enrollment from 1 year before to 91 d after diagnosis, were included. Patients who received an antiviral within 48 h of diagnosis were identified and propensity score-matched to a comparator cohort of untreated patients on baseline demographics, comorbid conditions, and HRU. Outcomes were assessed at days 30 and 90 after diagnosis and included respiratory-related complications (all respiratory-related and selected respiratory-related conditions [influenza, asthma, chronic obstructive pulmonary disease, or infection]), HRU, and costs.

RESULTS

Treated and matched untreated cohorts each consisted of 362,818 patients. HRU was significantly lower in the treated cohort compared with the untreated cohort at 30 and 90 d after diagnosis, respectively (hospitalizations: 0.6% vs. 0.8% and 1.2% vs. 1.6%; emergency department [ED] visits: 4.1% vs. 4.9% and 7.9% vs. 9.2%; intensive care unit/critical care unit (ICU/CCU) admissions: 0.2% vs. 0.4% and 0.4% vs. 0.6%). Respiratory-related HRU was lower in the treated cohort at both 30 and 90 d after diagnosis (p < .0001 for both periods). Mean all-cause total costs (including prescription costs) were significantly reduced in the treated group (day 30: $633 vs. $778; day 90: $1778 vs. $2119), despite higher prescription costs in the treated group.

LIMITATIONS

The study was retrospective and subject to residual selection bias, despite propensity score matching. Additionally, despite its potential relevance to influenza severity, vaccination status was not available in our data.

CONCLUSIONS

Antiviral influenza treatment is associated with a significant reduction in complications, HRU, and costs at 30 and 90 d after diagnosis.

A Cross-Sectional Study of Blood Ethylmercury Levels and Cognitive Decline Among Older Adults and the Elderly in the United States

Cognitive health is an emerging public health concern for the aging American population. Mercury (Hg) is a toxic element that can cause nervous system damage. This hypothesis-testing study evaluated the relationship between blood ethyl-Hg levels and cognitive decline in an older adult and elderly American population. A total of 1,821,663 weighted-persons between 60-80 years old with detectable blood ethyl-Hg levels within the 2011-2012 National Health and Nutritional Examination Survey were examined. Those persons with blood ethyl-Hg levels greater than the median were deemed the higher ethyl-Hg exposure group and those with ethyl-Hg levels less than the median were deemed the lower ethyl-Hg exposure group. Three tests were utilized to measure cognitive function: 1) Consortium to Establish a Registry for Alzheimer's Disease - Word List Learning (CERAD W-L) delayed recall test, 2) animal fluency test, and 3) Digit Symbol Substitution Test. Each cognitive test score was categorized as higher for those with scores greater than the median and lower for those with scores less than the median. Survey logistic regression modeling with covariates was used to analyze the data for the relationship between blood ethyl-Hg levels and cognitive function scores. Significantly increased risks for lower animal fluency test (odds ratio (OR) = 13.652, p = 0.0029) and CERAD W-L delayed recall test (OR = 6.401, p = 0.0433) scores were observed among the higher ethyl-Hg exposure group as compared to the lower ethyl-Hg exposure group. This study supports the hypothesis that increased ethyl-Hg exposure is associated with significant cognitive decline in older adult and elderly Americans.

Characteristics of Repeated Influenza Vaccination Among Older U.S. Adults

INTRODUCTION

Annual influenza vaccination is associated with reduced mortality among older adults and lower overall public health burden of influenza. This study seeks to identify the characteristics associated with repeat influenza vaccination and determine whether age-group (51-59, 60-69, ≥70 years) differences exist.

METHODS

Using the nationally representative, longitudinal Health and Retirement Study waves 2004, 2008, 2012, and 2016, adults aged >50 years were followed from 2004 to 2016. In 2020, age-stratified, multinomial regression models were estimated to identify the factors associated with respondents receiving the vaccine repeatedly (every time point), occasionally (some years), or never, with censoring for death.

RESULTS

The overall proportion of adults repeatedly receiving influenza vaccine monotonically increased across age groups from 25.9% among adults aged 51-59 years to 62.4% among those aged ≥70 years. Black, non-Hispanics and smokers were less likely to repeatedly receive an influenza vaccine than white, non-Hispanics and nonsmokers (RR=0.40-0.61 and RR=0.60-0.75, respectively, p<0.05 for all). Those who had 1‒4 medical doctor visits in the past 2 years (RR=1.60-2.99) or cholesterol screening (RR=2.67-3.48) in the past 2 years were significantly more likely to repeatedly receive influenza vaccine than those who had none.

CONCLUSIONS

Although adults aged 60-69 years and ≥70 years are more likely to receive influenza vaccine repeatedly than adults aged 51-59 years, age-specific interventions for repeat influenza vaccination may not be as effective as interventions targeted to certain subgroups among adults aged ≥51 years.

Shingles Vaccination of U.S. Adults Aged 50-59 Years and ≥60 Years Before Recommendations for Use of Recombinant Zoster Vaccine

INTRODUCTION

In 2006, zoster vaccine live was recommended for adults aged ≥60 years. In 2011, zoster vaccine live was approved for use but not recommended for adults aged 50-59 years. This study assessed zoster vaccine live coverage among adults aged 50-59 years and ≥60 years.

METHODS

Data from the 2013-2017 National Health Interview Surveys were analyzed in 2019 to estimate national zoster vaccine live coverage among adults aged ≥50 years. State-specific zoster vaccine live coverage among adults aged ≥50 years was assessed using 2017 Behavioral Risk Factor Surveillance System data.

RESULTS

Among adults aged 50-59 years, zoster vaccine live coverage was 5.7% in 2017, ranging from 4% to 6% during 2013-2017 (test for trend, p>0.05). Zoster vaccine live coverage among adults aged 50-59 years ranged from 5.8% in Pennsylvania to 14.7% in South Dakota. By 2017, zoster vaccine live was received by 34.9% of adults aged ≥60 years, a significant increase from 24.2% in 2013. Zoster vaccine live coverage among adults aged ≥60 years in 2017 ranged from 26.0% in Mississippi to 51.8% in Vermont. In 2017, major characteristics significantly associated with increased likelihood of zoster vaccine live vaccination among adults aged 50-59 years and ≥60 years were older age, having 4 to 9 physician contacts in the past 12 months, and having a usual place for health care.

CONCLUSIONS

This study provides an assessment of zoster vaccine live coverage among adults aged ≥50 years before the newly recommended recombinant zoster vaccine came into widespread use. Providers should routinely assess adults' vaccination status and strongly recommend or offer needed vaccines to their patients.

Large-scale influenza vaccination promotion on a mobile app platform: A randomized controlled trial

While health-care providers have used incentives in an attempt to motivate patients to obtain vaccinations, their effect on vaccination rates has not been systematically evaluated on a large scale. In this study, we examined whether mobile applications may improve population vaccination rates through enhanced communication and incentives education. Our study is the first randomized controlled trial assessing the effect of large-scale messaging combined with individualized incentives on influenza-vaccination rates. In this trial, we delivered messages regarding influenza vaccinations to 50,286 adults, aged 18 through 65, then compared the subsequent vaccination rate, the effectiveness of the message content and the timing. Multiple rounds of messaging occurred over a seven-week period during the 2016 flu season, after which vaccination rates were observed for one week. Participants were randomly assigned to one of three messaging approaches: conspicuous (highlighting the amount of rewards to be received for obtaining a flu shot); generic (promoting vaccinations with no mention of rewards); or no-message. Evidence of vaccination obtainment was indicated by medical and pharmacy claims, augmented by patients self-reporting through the mobile wellness app during the study period. Of the people assigned to receive messaging, 23.2% obtained influenza vaccination, compared to 22.0% of people who obtained vaccination in the no-messaging control arm. This difference was statistically significant (p < 0.01). The research revealed that messaging effectiveness decreased after each successive batch sent, suggesting that most participants responsive to messaging would become activated immediately after receiving one alert. Interestingly, in this large-scale study, there were no significant differences between conspicuous incentives and generic messaging, suggesting an important area for future research. Trial Registration: clinicaltrials.gov identifier: NCT02908893.

A double-blind, randomized controlled trial to evaluate the safety and immunogenicity of an intranasally administered trivalent inactivated influenza vaccine with the adjuvant LTh(αK): A phase II study

BACKGROUND

Intranasal influenza vaccines may provide protective efficacy by inducing both systemic antibodies and local secretory IgA. Live attenuated intranasal vaccines are not feasible for high-risk groups. A previously constructed inactivated vaccine with adjuvant revealed an association with neurological events in some studies. In this phase II trial, we aimed to evaluate the safety and immunogenicity of an intranasal influenza vaccine with a novel adjuvant, heat-labile enterotoxin (LT)-derived from E. coli (LTh(αK)).

METHODS

This study is a multicenter, randomized controlled, double-blind, phase II trial of an intranasal influenza vaccine containing 22.5 μg of the hemagglutinin (HA) antigen of three influenza strains in combination with 2 different LTh(αK) adjuvant doses (group 1: 30 μg; group 2: 45 μg) in subjects 20-70 years old. The control vaccine was 22.5 μg of influenza HA antigen alone (group 3). The vaccine was intranasally administered on days 1 and 8. Serum anti-HA antibody and nasal secretory IgA were measured, and adverse events (AEs) were recorded prevaccination and 29 (±2) days postvaccination.

RESULTS

Of 354 participants randomized in the study, 340 received two vaccine doses. AEs were mostly mild, and there was no discontinuation related to the vaccine. Only a higher frequency of diarrhea after the first dose was noted among group 2 (11.5%) than among group 3 (2.8%), and there was no significant difference after the second dose. The three groups had comparable serum anti-HA antibody immunogenicity. However, the adjuvanted vaccines induced greater mucosal IgA antibody production than the control vaccine. In a subgroup analysis, group 1 participants achieved adequate immunogenicity among both 20- to 60- and 61- to 70-year-old participants.

CONCLUSION

The intranasal influenza vaccine adjuvanted with LTh(αK) is generally safe and could provide systemic and local antibody responses. Adjuvanted vaccines were significantly more immunogenic than the nonadjuvanted control vaccine in mucosal immunity. ClinicalTrials.gov Identifier: NCT03784885.

Influenza in obese travellers: increased risk and complications, decreased vaccine effectiveness

BACKGROUND

Obesity is a worldwide epidemic and was empirically shown to increase the risk of developing severe influenza virus infection. As international travel becomes more common and obesity is now prevalent even in low- and middle-income countries, travellers may have an increased risk of contracting influenza virus especially during peak influenza season.

METHODS

An analysis of the literature, centred on publications from 2014-19, was performed, with an emphasis on human epidemiological data, human studies ex vivo and studies in mouse models of obesity. Our search efforts focused on influenza disease severity, pathogenesis, evolutionary dynamics and measures of infection control in the obese and overweight host.

RESULTS

Obesity is associated with an increased risk of infection, as well as a greater chance for hospitalization and severe complications. Studies in mouse models of obesity have uncovered that obese hosts suffer increased viral spread, delayed viral clearance and heightened damage to the respiratory epithelium. Innate and adaptive immune responses are delayed, thus increasing morbidity and mortality. Further, infection control measures, including vaccination and antivirals, prove less effective in obese hosts. Finally, the obese microenvironment allows for increased duration and amount of viral shedding and potentially increases the chance for emergence of virulent minor variants in the viral population. Together, obese hosts are at high risk of influenza infection, as well as severe sequelae following infection.

CONCLUSION

Obese travellers should be aware of influenza activity in the regions visited, as well as take protective measures prior to travel. Vaccination is highly recommended for all travellers, but especially highly susceptible obese travellers.

Progress in Vaccine-Preventable and Respiratory Infectious Diseases-First 10 Years of the CDC National Center for Immunization and Respiratory Diseases, 2006-2015

The need for closer linkages between scientific and programmatic areas focused on addressing vaccine-preventable and acute respiratory infections led to establishment of the National Center for Immunization and Respiratory Diseases (NCIRD) at the Centers for Disease Control and Prevention. During its first 10 years (2006–2015), NCIRD worked with partners to improve preparedness and response to pandemic influenza and other emergent respiratory infections, provide an evidence base for addition of 7 newly recommended vaccines, and modernize vaccine distribution. Clinical tools were developed for improved conversations with parents, which helped sustain childhood immunization as a social norm. Coverage increased for vaccines to protect adolescents against pertussis, meningococcal meningitis, and human papillomavirus–associated cancers. NCIRD programs supported outbreak response for new respiratory pathogens and oversaw response of the Centers for Disease Control and Prevention to the 2009 influenza A(H1N1) pandemic. Other national public health institutes might also find closer linkages between epidemiology, laboratory, and immunization programs useful.

Attitudes and beliefs of healthcare workers about influenza vaccination

BACKGROUND

Annual influenza vaccination is recommended for all healthcare workers (HCWs) to help reduce the risk of contracting the virus and transmitting it to vulnerable people, especially older adults in residential care facilities. Vaccination uptake among HCWs remains low.

AIM

To investigate HCWs' attitudes towards, and beliefs about, seasonal influenza vaccination in a residential care facility for older adults in the Republic of Ireland.

METHOD

Data were collected using a self-administered questionnaire.

RESULTS

A total of 95 questionnaires were distributed, and 35 (37%) HCWs completed and returned them. During the 2016-17 flu season, 20 (57%) respondents were vaccinated. Primary predictors of vaccination acceptance were the belief that being healthy should not mitigate against requiring the vaccine ( r =0.7, P =0.01), protection of self and family ( r =0.67, P =0.01), protection of patients ( r =0.592, P =0.01) and agreement with mandatory vaccination ( r =0.351, P =0.039). Reasons for vaccination avoidance were misconceptions about the need for vaccination among healthy HCWs (67%), efficacy of the vaccine (60%), lack of trust in the vaccine (47%) and a belief that the vaccine may cause flu (47%).

CONCLUSION

Addressing HCWs' beliefs relating to the personal benefits of vaccination while simultaneously correcting misconceptions may help to increase uptake among those working in residential care settings for older adults.

Racial/Ethnic Disparities in Influenza Vaccination Coverage Among US Adolescents, 2010-2016

OBJECTIVE

Although research suggests racial/ethnic disparities in influenza vaccination and mortality rates, few studies have examined racial/ethnic trends among US adolescents. We used national cross-sectional data to determine (1) trends in influenza vaccination rates among non-Hispanic white (hereinafter, white), non-Hispanic black (hereinafter, black), and Hispanic adolescents over time and (2) whether influenza vaccination rates among adolescents varied by race/ethnicity.

METHODS

We analyzed provider-reported vaccination histories for 2010-2016 from the National Immunization Survey-Teen. We used binary logistic regression models to determine trends in influenza vaccination rates by race/ethnicity for 117 273 adolescents, adjusted for sex, age, health insurance, physician visit in the previous 12 months, vaccination facility type, poverty status, maternal education level, children in the household, maternal marital status, maternal age, and census region of residence. We calculated adjusted probabilities for influenza vaccination for each racial/ethnic group, adjusted for the same demographic characteristics.

RESULTS

Compared with white adolescents, Hispanic adolescents had higher odds (adjusted odds ratio [aOR] = 1.11; 95% confidence interval [CI], 1.06-1.16) and black adolescents had lower odds (aOR = 0.95; 95% CI, 0.90-1.00) of vaccination. Compared with white adolescents, Hispanic adolescents had significantly higher adjusted probabilities of vaccination for 2011-2013 (2011: 0.22, P < .001; 2012: 0.23, P < .001; 2013: 0.26, P < .001). Compared with white adolescents, black adolescents had significantly lower probabilities of vaccination for 2016 (2016: 0.21, P < .001).

CONCLUSIONS

Targeted interventions are needed to improve adolescent influenza vaccination rates and reduce racial/ethnic disparities in adolescent vaccination coverage.

Influenza Vaccination Coverage Among English-Speaking Asian Americans

INTRODUCTION

English-speaking non-Hispanic Asians (Asians) in the U.S. include populations with multiple geographic origins and ethnicities (e.g., Asian Indian, Chinese, Filipino, Japanese, Korean, and Vietnamese). Health behaviors and outcomes can differ widely among Asian ethnicities, and highlight the importance of subgroup analysis. Aggregating Asians may mask differences in influenza vaccination across various ethnicities.

METHODS

Combined data from 2013 to 2015 Behavioral Risk Factor Surveillance System, a population-based, telephone survey of the non-institutionalized, U.S. population aged ≥18years, were analyzed in 2017 to assess influenza vaccination among Asians. Weighted proportions were calculated. Multivariable logistic regression was used to determine independent associations between sociodemographic factors and receipt of influenza vaccination.

RESULTS

Influenza vaccination varied widely among Asian ethnicities, both nationally and by state. Overall, 42.1% of Asians reported having received an influenza vaccine, similar to vaccination among whites (42.4%). Coverage ranged from 36.1% among Koreans to 50.9% among Japanese. Factors independently associated with influenza vaccination among some or all Asian ethnicities included age (≥50 years), female, never married, high school or higher education, annual household income ≥$75,000, possession of medical insurance and personal healthcare provider, routine checkup in the previous year, and presence of certain chronic conditions.

CONCLUSIONS

Though Asians and whites had similar overall influenza vaccination coverage, differences existed between Asian ethnicities, both nationally and by state. This information may help community-based, state-level, and national-level public health agencies to support targeted approaches for outreach to these populations, such as improving cultural and linguistic access to care, to improve influenza vaccination.

U.S. clinicians' and pharmacists' reported barriers to implementation of the Standards for Adult Immunization Practice

BACKGROUND

The Standards for Adult Immunization Practice (Standards), revised in 2014, emphasize that adult-care providers assess vaccination status of adult patients at every visit, recommend vaccination, administer needed vaccines or refer to a vaccinating provider, and document vaccinations administered in state/local immunization information systems (IIS). Providers report numerous systems- and provider-level barriers to vaccinating adults, such as billing, payment issues, lower prioritization of vaccines due to competing demands, and lack of information about the use and utility of IIS. Barriers to vaccination result in missed opportunities to vaccinate adults and contribute to low vaccination coverage. Clinicians' (physicians, physician assistants, nurse practitioners) and pharmacists' reported barriers to assessment, recommendation, administration, referral, and documentation, provider vaccination practices, and perceptions regarding their adult patients' attitudes toward vaccines were evaluated.

METHODS

Data from non-probability-based Internet panel surveys of U.S. clinicians (n = 1714) and pharmacists (n = 261) conducted in February-March 2017 were analyzed using SUDAAN. Weighted proportion of reported barriers to assessment, recommendation, administration, referral, and documentation in IIS were calculated.

RESULTS

High percentages (70.0%-97.4%) of clinicians and pharmacists reported they routinely assessed, recommended, administered, and/or referred adults for vaccination. Among those who administered vaccines, 31.6% clinicians' and 38.4% pharmacists' submitted records to IIS. Reported barriers included: (a) assessment barriers: vaccination of adults is not within their scope of practice, inadequate reimbursement for vaccinations; (b) administration barriers: lack of staff to manage/administer vaccines, absence of necessary vaccine storage and handling equipment and provisions; and (c) documentation barriers: unaware if state/city has IIS that includes adults or not sure how their electronic system would link to IIS.

CONCLUSION

Although many clinicians and pharmacists reported implementing most of the individual components of the Standards, with the exception of IIS use, there are discrepancies in providers' reported actual practices and their beliefs/perceptions, and barriers to vaccinating adults remain.

Clinical characteristics of patients with laboratory-confirmed influenza A(H1N1)pdm09 during the 2013/2014 and 2015/2016 clade 6B/6B.1/6B.2-predominant outbreaks

A novel pandemic influenza A(H1N1)pdm09 virus emerged in 2009 globally, and it continues to circulate in humans. The National Influenza Surveillance Network in Taiwan identified five A(H1N1)pdm09-predominant seasons, representing the 2009/2010, 2010/2011, 2012/2013, 2013/2014, and 2015/2016 outbreaks from 2009 to 2016. Independently, a retrospective cohort study (which enrolled 639 infected patients during the five seasons) was conducted at Chang Gung Memorial Hospital to explore the risk factors associated with influenza A(H1N1)pdm09-related complications. A phylogenetic analysis of hemagglutinin (HA) sequences showed that the circulating A(H1N1)pdm09 virus belonged to clades 1, 2, and 8 in 2009/2010; clades 3, 4, 5, and 7 in 2010/2011; clades 7 and 6C in 2012/2013; clades 6B in 2013/2014; and 6B/6B.1/6B.2 in 2015/2016. Compared to individuals infected in non-6B/6B.1/6B.2 seasons (2009/2010, 2010/2011, and 2012/2013), those infected in 6B/6B.1/6B.2 seasons (2013/2014 and 2015/2016) were at higher risk for influenza-related complications (adjusted odds ratio [aOR]: 1.6, 95% confidence interval [CI]: 1.0–2.8), pneumonia (aOR: 1.78, 95% CI: 1.04–3.04), mechanical ventilation (aOR: 2.6, 95% CI: 1.2–5.6), and acute respiratory distress syndrome (aOR: 5.5, 95% CI: 1.9–15.9). For the increased severity of infection during the influenza A(H1N1)pdm09 clade 6B/6B.1/6B.2 seasons, aspects related to the antigenic change of A(H1N1)pdm09 virus, immune response of the host, and environmental factors required further investigation.

Receipt and effectiveness of influenza vaccination reminders for adults, 2011-2012 season, United States

BACKGROUND

Reminders for influenza vaccination improve influenza vaccination coverage. The purpose of this study was to describe the receipt of reminders for influenza vaccination during the 2011-12 influenza season among US adults.

METHODS

We analyzed data from the March 2012 National Flu Survey (NFS), a random digit dial telephone survey of adults in the United States. Relative to July 1, 2011, respondents were asked whether they received a reminder for influenza vaccination and the source and type of reminder they received. The association between reminder receipt and demographic variables, and the association between influenza vaccination coverage and receipt of reminders were also examined.

RESULTS

Of adults interviewed, 17.2% reported receiving a reminder since July 1, 2011. More than half (65.2%) of the reminders were sent by doctor offices. Hispanics and non-Hispanic blacks were more likely than non-Hispanic whites to report receiving a reminder. Adults who reported having a usual healthcare provider, health insurance, or a high-risk condition were more likely to report receiving reminders than the respective reference group. Adults reporting receipt of reminders were 1.15 times more likely (adjusted prevalence ratio, 95% CI: 1.06-1.25) to report being vaccinated for influenza than adults reporting not receiving reminders.

CONCLUSIONS

Differences exist in receipt of influenza vaccination reminders among adults. Reminders are important tools to improve adult influenza vaccination coverage. Greater use of reminders may lead to higher rates of adult influenza vaccination coverage and reductions in influenza-related morbidity.

Preventive behaviors adults report using to avoid catching or spreading influenza, United States, 2015-16 influenza season

INTRODUCTION

Influenza vaccination can prevent influenza and potentially serious influenza-related complications. Although the single best way to prevent influenza is annual vaccination, everyday preventive actions, including good hygiene, health, dietary, and social habits, might help, too. Several preventive measures are recommended, including: avoiding close contact with people who are sick; staying home when sick; covering your mouth and nose when coughing or sneezing; washing your hands often; avoiding touching your eyes, nose, and mouth; and practicing other good health habits like cleaning and disinfecting frequently touched surfaces, getting plenty of sleep, and drinking plenty of fluids. Understanding public acceptance and current usage of these preventive behaviors can be useful for planning both seasonal and pandemic influenza prevention campaigns. This study estimated the percentage of adults in the United States who reported practicing preventive behaviors to avoid catching or spreading influenza, and explored associations of reported behaviors with sociodemographic factors.

METHODS

We analyzed data from 2015 National Internet Flu Survey, a nationally representative probability-based Internet panel survey of the non-institutionalized U.S. population ≥18 years. The self-reported behaviors used to avoid catching or spreading influenza were grouped into four and three non-mutually exclusive subgroups, respectively. Weighted proportions were calculated. Multivariable logistic regression models were used to calculate adjusted prevalence differences and to determine independent associations between sociodemographic characteristics and preventive behavior subgroups.

RESULTS

Common preventive behaviors reported were: 83.2% wash hands often, 80.0% cover coughs and sneezes, 78.2% stay home if sick with a respiratory illness, 64.4% avoid people sick with a respiratory illness, 51.7% use hand sanitizers, 50.2% get treatment as soon as possible, and 49.8% report getting the influenza vaccination. Race/ethnicity, gender, age, education, income, region, receipt of influenza vaccination, and household size were associated with use of preventive behaviors after controlling for other factors.

CONCLUSION

Many adults in the United States reported using preventive behaviors to avoid catching or spreading influenza. Though vaccination is the most important tool available to prevent influenza, the addition of preventive behaviors might play an effective role in reducing or slowing transmission of influenza and complement prevention efforts.

Racial disparities in vaccination for seasonal influenza in early childhood

OBJECTIVES

Influenza vaccination is the best protection against infection and severe complications of disease, such as hospitalization and death. Therefore, it is important to accurately estimate vaccination coverage and to evaluate the role of race/ethnicity. This study examines racial disparities in influenza vaccination among children using a nationally representative sample.

STUDY DESIGN

This study used cross-sectional data from the 2009-2014 National Immunization Survey for children aged 19-35 months (n = 98,186) in the United States.

METHODS

The outcome variable was receipt of influenza vaccination (yes/no) and exposure variable was race/ethnicity. Weighted multivariate logistic regression was used to estimate the odds ratio and 95% confidence intervals (CIs) for the effect of race/ethnicity on receipt of the influenza vaccine.

RESULTS

The overall vaccination rates were 81.6% for non-Hispanic whites, 79.2% for Hispanics, 80.5% for non-Hispanic blacks, and 80.7% for non-Hispanic mixed/other. In the adjusted model, compared with non-Hispanic white children, Hispanic children were 13% less likely to receive influenza vaccination within the last 12 months (adjusted odds ratio [aOR] = 0.87; 95% CI: 0.80-0.94). In addition, children aged 24-29 months (aOR = 0.48; 95% CI: 0.44-0.52) and 30-35 months (aOR = 0.33; 95% CI: 0.30-0.36) were significantly less likely to receive influenza vaccination within the last 12 months compared with those who were 19-23 months old.

CONCLUSIONS

There were differences in influenza vaccination rates among different racial groups. Hispanic children had the lowest vaccination rates. Findings from our study have significant implications for targeted interventions to increase the overall vaccination rate for children in the United States.

Local-Level Adult Influenza and Pneumococcal Vaccination Disparities: Chicago, Illinois, 2015-2016

OBJECTIVES

To investigate local-level adult influenza and pneumococcal vaccination disparities to inform targeted interventions.

METHODS

Questions on influenza and pneumococcal vaccination uptake were included in a door-to-door community-based representative survey conducted in 10 Chicago, Illinois, neighborhoods in 2015 and 2016. A total of 1543 adults completed the survey, including 172 adults aged 65 years or older. We calculated adult influenza (≥ 18 years) and pneumococcal (≥ 65 years) vaccination coverage by community area and respondent characteristics.

RESULTS

We observed significant differences in pneumococcal vaccination coverage between community areas (range = 18%-91%). Influenza vaccination coverage differed by gender, age, insurance coverage, acculturation, and confidence or trust in physician. Non-Hispanic Blacks were more likely to be vaccinated when they had higher confidence or trust in their physician (45% vs 20%; P < .01). Mexicans who reported less acculturation were more likely to be vaccinated than were Mexicans who were more acculturated (41% vs 27%; P = .02).

CONCLUSIONS

Striking disparities between neighborhoods and racial/ethnic groups in adult influenza and pneumococcal vaccination coverage highlight the need for improved local-level immunization coverage data.

Urgent challenges in implementing live attenuated influenza vaccine

Conflicting reports have emerged about the effectiveness of the live attenuated influenza vaccine. The live attenuated influenza vaccine appears to protect particularly poorly against currently circulating H1N1 viruses that are derived from the 2009 pandemic H1N1 viruses. During the 2015-16 influenza season, when pandemic H1N1 was the predominant virus, studies from the USA reported a complete lack of effectiveness of the live vaccine in children. This finding led to a crucial decision in the USA to recommend that the live vaccine not be used in 2016-17 and to switch to the inactivated influenza vaccine. Other countries, including the UK, Canada, and Finland, however, have continued to recommend the use of the live vaccine. This policy divergence and uncertainty has far reaching implications for the entire global community, given the importance of the production capabilities of the live attenuated influenza vaccine for pandemic preparedness. In this Personal View, we discuss possible explanations for the observed reduced effectiveness of the live attenuated influenza vaccine and highlight the underpinning scientific questions. Further research to understand the reasons for these observations is essential to enable informed public health policy and commercial decisions about vaccine production and development in coming years.

Individual, Cultural and Structural Predictors of Vaccine Safety Confidence and Influenza Vaccination Among Hispanic Female Subgroups

Rates of influenza vaccination among US Hispanics are lower than for non-Hispanic whites, yet little is known about factors affecting vaccination in this population. Additionally, although Hispanics are a diverse population with culturally distinct subgroups, they are often treated as a homogenous population. This study (1) examines how confidence in vaccine safety and influenza vaccine use vary by Hispanic subgroup and (2) identifies individual, cultural and structural correlates of these outcomes. This study analyzed survey data from 1565 Hispanic women who were recruited at clinic- and community-based sites in Los Angeles. Education, healthcare coverage, acculturation, fatalism, and religiosity were predictors of influenza vaccination behavior and predictors varied by subgroup. These findings provide guidance for how influenza vaccine promotion efforts can be developed for Hispanic subgroups. Confidence in the safety of a vaccine is a major predictor of flu vaccination and an important modifiable target for intervention.

Recommendations and offers for adult influenza vaccination, 2011-2012 season, United States

BACKGROUND

Provider recommendations and offers for influenza vaccination improve adult influenza vaccination coverage. Analysis was performed to describe receipt of influenza vaccination recommendations and offers among adults who visited a healthcare provider (HCP) during the 2011-2012 influenza season and describe differences between those receiving and not receiving recommendations and offers for influenza vaccination. Associations between influenza vaccination and receipt of recommendations and offers were examined.

METHODS

Respondents to a random digit dial telephone survey who had visited a HCP since July 1, 2011 were asked if they had received a recommendation for influenza vaccination. Those receiving a recommendation were asked if they received an offer for vaccination. Participants were characterized by demographic and access to health care variables. Logistic regression was used to examine the relationships between participant characteristics and recommendation alone, between participant characteristics and recommendation and offer, and between influenza vaccination and recommendation and offer.

RESULTS

Of those who reported visiting a HCP, 43.8% reported receiving a recommendation for influenza vaccination. Of those who reported receiving a recommendation, 76.6% reported receiving an offer for influenza vaccination. Persons with high-risk conditions and persons over 65 years were more likely to receive recommendations for influenza vaccination when compared to those without high-risk conditions and 18-49 year olds, respectively. Those reporting receipt of a recommendation and offer for influenza vaccination were 1.76 times more likely and those reporting receipt of a recommendation but no offer were 1.72 times more likely to report being vaccinated for influenza controlling for all patient characteristics.

CONCLUSIONS

Less than half of respondents reported receipt of recommendations and offers of influenza vaccination during the 2011-2012 influenza season and disparities exist between groups. All healthcare providers seeing adults should recommend or offer influenza vaccination for all patients at every visit during the influenza season.

Racial and Ethnic Disparities in Influenza Vaccination among Adults with Chronic Medical Conditions Vary by Age in the United States

BACKGROUND

People living with chronic health conditions exhibit higher risk for developing severe complications from influenza according to the Centers for Diseases Control and Prevention. Although racial and ethnic disparities in influenza vaccination have been documented, it has not been comprehensively determined whether similar disparities are present among the adult population with at least one such condition.

OBJECTIVE

To study if racial and ethnic disparities in relation to influenza vaccination are present in adults suffering from at least one chronic condition and if such inequalities differ between age groups.

METHODS

The Medical Expenditure Panel Survey (2011-2012) was used to study the adult population (age ≥18) who had at least one chronic health condition. Baseline differences in population traits across racial and ethnic groups were identified using a chi-square test. This was conducted among various age groups. In addition, survey logistic regression was utilized to produce odds ratios of receiving influenza vaccination annually between racial and ethnic groups.

RESULTS

The total sample consisted of 15,499 adults living with at least one chronic health condition. The numbers of non-Hispanic whites (whites), non-Hispanic blacks (blacks), and Hispanics were 8,658, 3,585, and 3,256, respectively. Whites (59.93%) were found to have a higher likelihood of self-reporting their receipt of the influenza vaccine in comparison to the black (48.54%) and Hispanic (48.65%) groups (P<0.001). When examining persons aged 50-64 years and ≥65 years, it was noted that the black (54.99%, 62.72%) and Hispanic (53.54%, 64.48%) population had lower rates of influenza vaccine coverage than the white population (59.22%, 77.89) (both P<0.0001). No significant differences between whites and the blacks or Hispanics were found among the groups among adults between 18 and 49 inclusive (P>0.05). After controlling for patient characteristics, the difference in influenza vaccine coverage between whites and the minority groups were no longer significant for adults aged 50-64 years. However, the difference were still statistically significant for those aged ≥65 years.

CONCLUSIONS

In the United States, there are significant disparities in influenza vaccination by race and ethnicity for adults over 65 years with at least one chronic health condition. Future research is needed to help develop more targeted interventions to address these issues and improve influenza vaccination rates.

Exploring the Continuum of Vaccine Hesitancy Between African American and White Adults: Results of a Qualitative Study

Vaccine delay and refusal present very real threats to public health. Since even a slight reduction in vaccination rates could produce major consequences as herd immunity is eroded, it is imperative to understand the factors that contribute to decision-making about vaccines. Recent scholarship on the concept of “vaccine hesitancy” emphasizes that vaccine behaviors and beliefs tend to fall along a continuum from refusal to acceptance. Most research on hesitancy has focused on parental decision-making about childhood vaccines, but could be extended to explore decision-making related to adult immunization against seasonal influenza. In particular, vaccine hesitancy could be a useful approach to understand the persistence of racial/ethnic disparities between African American and White adults. This study relied on a thematic content analysis of qualitative data, including 12 semi-structured interviews, 9 focus groups (N=90), and 16 in-depth interviews, for a total sample of 118 (N=118) African American and White adults. All data were transcribed and analyzed with Atlas.ti. A coding scheme combining both inductive and deductive codes was utilized to identify themes related to vaccine hesitancy. The study found a continuum of vaccine behavior from never-takers, sometimes-takers, and always-takers, with significant differences between African Americans and Whites.  We compared our findings to the Three Cs: Complacency, Convenience, and Confidence framework. Complacency contributed to low vaccine acceptance with both races.  Among sometimes-takers and always-takers, convenience was often cited as a reason for their behavior, while never-takers of both races were more likely to describe other reasons for non-vaccination, with convenience only a secondary explanation.  However, for African Americans, cost was a barrier.  There were racial differences in trust and confidence that impacted the decision-making process. The framework, though not a natural fit for the data, does provide some insight into the differential sources of hesitancy between these two populations. Complacency and confidence clearly impact vaccine behavior, often more profoundly than convenience, which can contribute either negatively or positively to vaccine acceptance. The Three Cs framework is a useful, but limited tool to understanding racial disparities. Understanding the distinctions in those cultural factors that drive lower vaccine confidence and greater hesitancy among African Americans could lead to more effective communication strategies as well as changes in the delivery of vaccines to increase convenience and passive acceptance.

Influenza Vaccination of Healthcare Personnel by Work Setting and Occupation-U.S., 2014

INTRODUCTION

Routine influenza vaccination of healthcare personnel (HCP) can reduce influenza-related illness and its potentially serious consequences among HCP and their patients. Influenza vaccination has been routinely recommended for HCP since 1984.

METHODS

Data from the 2013 and 2014 National Health Interview Survey were analyzed in 2015. Kaplan-Meier survival estimated the cumulative proportion of HCP reporting 2013-2014 season influenza vaccination. Vaccination coverage by work setting and occupation were assessed. Multivariable logistic regression and predictive marginal analyses identified factors independently associated with vaccination among HCP.

RESULTS

Influenza vaccination coverage was 64.9% among HCP aged ≥18 years (95% CI=60.5%, 69.3%), which was significantly higher compared with non-HCP among the same age group (41.0%, 95% CI=39.8%, 42.1%) (p<0.05). Vaccination coverage was higher among physicians (82.3%) and nurses (77.5%) than other types of HCP (range, 50.2%-65.6%). Coverage was higher among HCP working in hospitals (76.9%) versus other settings (range, 53.9%-60.2%). Characteristics independently associated with an increased likelihood of vaccination among HCP were older age, higher education, having more physician contacts, and having health insurance. Having never been married was independently associated with decreased likelihood of vaccination among HCP.

CONCLUSIONS

Influenza vaccination coverage was higher among HCP than non-HCP, but still below the national target of 90%. Vaccination coverage varied widely by occupation type, work settings, and demographic characteristics. Evidence-based interventions, such as making vaccine available at no cost in the workplace and active promotion of vaccination, are needed to increase influenza vaccination among HCP in all healthcare settings.

Racial and ethnic disparities in vaccination coverage among adult populations in the U.S

INTRODUCTION

Reducing racial/ethnic disparities in immunization rates is a compelling public health goal. Disparities in childhood vaccination rates have not been observed in recent years for most vaccines. The objective of this study is to assess adult vaccination by race/ethnicity in the U.S.

METHODS

The 2012 National Health Interview Survey was analyzed in 2014 to assess adult vaccination by race/ethnicity for five vaccines routinely recommended for adults: influenza, tetanus, pneumococcal (two vaccines), human papilloma virus, and zoster vaccines. Multivariable logistic regression analysis was performed to identify factors independently associated with all adult vaccinations.

RESULTS

Vaccination coverage was significantly lower among non-Hispanic blacks, Hispanics, and non-Hispanic Asians compared with non-Hispanic whites, with only a few exceptions. Age, sex, education, health insurance, usual place of care, number of physician visits in the past 12 months, and health insurance were independently associated with receipt of most of the examined vaccines. Racial/ethnic differences narrowed, but gaps remained after taking these factors into account.

CONCLUSIONS

Racial and ethnic differences in vaccination levels narrow when adjusting for socioeconomic factors analyzed in this survey, but are not eliminated, suggesting that other factors that are associated with vaccination disparities are not measured by the National Health Interview Survey and could also contribute to the differences in coverage. Additional efforts, including systems changes to ensure routine assessment and recommendations for needed vaccinations among adults for all racial/ethnic groups, are essential for improving vaccine coverage.

Persistent racial and ethnic disparities in flu vaccination coverage: Results from a population-based study

BACKGROUND

The Advisory Committee on Immunization Practices recommends annual flu vaccination for all adults. We aimed to identify predictors of receiving a flu vaccination, with an emphasis on the impact of race and ethnicity.

METHODS

We used data from the 2011-2012 California Health Interview Survey and included all individuals aged ≥18 years. We performed a survey-weighted logistic regression on receipt of flu vaccination within the last year, adjusted by demographic and socioeconomic variables, and calculated odds ratios (ORs) and 95% confidence intervals (CIs).

RESULTS

Our study included a population-weighted sample of 27,796,484 individuals. Overall, 35.8% received a flu vaccination within the last year. Blacks were 33% less likely (95% CI, 21%-43%) to have been vaccinated than whites. Conversely, Koreans (OR, 1.77; 95% CI, 1.35-2.33) and Vietnamese (OR, 1.57; 95% CI, 1.19-2.07) were more likely than whites to have been vaccinated. No differences were seen between whites and the remaining racial and ethnic groups (Latino, Japanese, Chinese, Filipino, South Asian, Asian other, and other).

CONCLUSIONS

Racial and ethnic disparities in flu vaccination uptake exist in California. Namely, blacks have lower vaccination rates than whites, and there are disparate vaccination rates among the Asian-American subgroups. Efforts to increase vaccination rates among these groups are needed.

Vaccination of healthcare workers: A review

Vaccine-preventable diseases are a significant cause of morbidity and mortality. As new vaccines are proving to be effective and as the incidence of some infections decreases, vaccination practices are changing. Healthcare workers (HCWs) are particularly exposed to and play a role in nosocomial transmission, which makes them an important target group for vaccination. Most vaccine-preventable diseases still carry a significant risk of resurgence and have caused outbreaks in recent years. While many professional societies favor vaccination of HCWs as well as the general population, recommendations differ from country to country. In turn, vaccination coverage varies widely for each microorganism and for each country, making hospitals and clinics vulnerable to outbreaks. Vaccine mandates and non-mandatory strategies are the subject of ongoing research and controversies. Optimal approaches to increase coverage and turn the healthcare workforce into an efficient barrier against infectious diseases are still being debated.

Uptake of Influenza Vaccination and Missed Opportunities Among Adults with High-Risk Conditions, United States, 2013

BACKGROUND

Since 1960, the Advisory Committee on Immunization Practices has recommended influenza vaccination for adults with certain high-risk conditions because of increased risk for complications from influenza infection. We assessed national influenza vaccination among persons ages 18-64 years with high-risk conditions.

METHODS

We analyzed data from the 2012 and 2013 National Health Interview Survey. The Kaplan-Meier survival analysis procedure was used to estimate the cumulative proportion of influenza vaccination among adults ages 18-64 years with high-risk conditions. Potential missed opportunities for influenza vaccination were also evaluated. Multivariable logistic regression and predictive marginal analyses were conducted to identify factors independently associated with vaccination.

RESULTS

Overall, 39.9 million adults ages 18-64 years (18.9%) had at least one high-risk condition. For adults ages 18-64 years with high-risk conditions, overall influenza vaccination coverage was 49.5%. Coverage among adults 50-64 years of age was significantly higher compared with those ages 18-49 years (59.3% vs 39.0%; P <.05). Among adults ages 18-64 years, coverage was 46.2% for those with chronic lung diseases, 50.5% for those with heart disease, 58.0% for those with diabetes, 62.5% for those with renal disease, and 56.4% for those with cancer. Overall, 90.1% reported at least one visit to a health care setting where vaccination could have been provided. Among adults ages 18-64 years with high-risk conditions, older age, being female, Hispanic ethnicity or Asian race, having one or more physician visits, a regular physician for health care, health insurance, and having ever received pneumococcal vaccination were independently associated with a higher likelihood of influenza vaccination. Being widowed/divorced/separated or never married and not being employed were independently associated with a lower likelihood of influenza vaccination.

CONCLUSIONS

Influenza vaccination coverage varies substantially by age and high-risk conditions but remains low. Approximately 50% of those with high-risk conditions remain unvaccinated. Health care providers should ensure they routinely assess influenza vaccination status, and recommend and offer vaccines to those with high-risk conditions.

Racial/Ethnic Disparities in Influenza Vaccination of Chronically Ill US Adults: The Mediating Role of Perceived Discrimination in Health Care

BACKGROUND

Despite well-established programs, influenza vaccination rates in US adults are well below federal benchmarks and exhibit well-documented, persistent racial and ethnic disparities. The causes of these disparities are multifactorial and complex, though perceived racial/ethnic discrimination in health care is 1 hypothesized mechanism.

OBJECTIVES

To assess the role of perceived discrimination in health care in mediating influenza vaccination RACIAL/ETHNIC disparities in chronically ill US adults (at high risk for influenza-related complications).

RESEARCH DESIGN

We utilized 2011-2012 data from the Aligning Forces for Quality Consumer Survey on health and health care (n=8127), nationally representative of chronically ill US adults. Logistic regression marginal effects examined the relationship between race/ethnicity and influenza vaccination, both unadjusted and in multivariate models adjusted for determinants of health service use. We then used binary mediation analysis to calculate and test the significance of the percentage of this relationship mediated by perceived discrimination in health care.

RESULTS

Respondents reporting perceived discrimination in health care had half the uptake as those without discrimination (32% vs. 60%, P=0.009). The change in predicted probability of vaccination given perceived discrimination experiences (vs. none) was large but not significant in the fully adjusted model (-0.185; 95% CI, -0.385, 0.014). Perceived discrimination significantly mediated 16% of the unadjusted association between race/ethnicity and influenza vaccination, though this dropped to 6% and lost statistical significance in multivariate models.

CONCLUSIONS

The causes of persistent racial/ethnic disparities are complex and a single explanation is unlikely to be sufficient. We suggest reevaluation in a larger cohort as well as potential directions for future research.

Factors influencing adults' immunization practices: a pilot survey study of a diverse, urban community in central Ohio

BACKGROUND

Adult vaccination rates in the United States are well below recommendations with disparities in race, ethnicity, and education level resulting in even lower rates for these populations. This study aimed to identify the barriers to and perceptions of immunizations in adults in an urban, underserved, multicultural community. Understanding the factors that influence adults' decisions to receive routinely recommended vaccines will aid health care providers and public health officials to design programs to improve vaccination rates.

METHODS

This cross-sectional, survey-based study was conducted in January 2014 in Columbus, Ohio. Participants were recruited from four urban federally-qualified health centers and four grocery stores affiliated with those clinics. The survey gathered self-reported receipt of immunizations, knowledge about indications for immunizations, and factors influencing decisions to receive an immunization. Data was analyzed in 2014. Descriptive statistics were generated for all survey items and Chi-Square or Fisher's Exact tests were used as appropriate to test for associations between demographic characteristics and factors influencing immunization decisions.

RESULTS

The top five factors likely to affect the decision to receive an immunization among the 304 respondents were: "doctor's recommendation" (80.6 %), "knowing why I should get a vaccine" (78.2 %), "knowing which vaccines I need" (75.5 %), cost (54.2 %), and "concern about getting sick if I get a vaccine" (54.0 %). Significant differences in factors influencing the immunization decision exist among respondents based on ethnicity and education level. For those participants with self-identified diabetes, heart disease, or asthma, less than half were aware that certain immunizations could reduce the risk of complications associated with their disease(s).

CONCLUSIONS

Data from this study may inform and shape patient education programs conducted in clinics, retailers, and communities, as well as advocacy efforts for adult immunizations. Results from this study suggest that patients would respond to programs for promoting vaccine uptake if they focused on benefits and indications for vaccines. The results also highlighted the need for education regarding immunizations for patients with chronic diseases and special indications. The differences in perceptions found between groups can be used to create targeted interventions based on the needs of those patient populations.

Diffusion of Pharmacy-Based Influenza Vaccination Over Time in the United States

OBJECTIVES

To examine pharmacy-based influenza vaccination using diffusion of innovation theory.

METHODS

We used 1993 to 2013 Behavioral Risk Factor Surveillance System data to generate weighted prevalence rates of influenza vaccination, stratified by age (18-64 years vs ≥ 65 years) and state of residence. The diffusion of innovation theory adopter categories were residents of states allowing pharmacist vaccination before 1996 ("innovator/early adopters"), between 1996 and 1998 ("early majority"), between 1999 and 2004 ("late majority"), and in 2007 or later ("laggards").

RESULTS

For adults aged 18 to 64 years, vaccination rates were similar before the innovation (1993), diverged as the innovation reached the majority (2003), and were significantly lower for laggard states by 2013. Younger adults' vaccination rates steadily increased from 12% to 16% in 1993 to 29% to 36% in 2013. For older adults, there was no significant difference in vaccination rates between adopter categories in any year and no advantage associated with adoption category.

CONCLUSIONS

Key features of pharmacy-based vaccination, including relative advantage and compatibility, are most relevant to younger adults; different interventions are warranted for older adults.

Trends in U.S. hospitalizations and inpatient deaths from pneumonia and influenza, 1996-2011

BACKGROUND

To reduce excess morbidity and mortality of pneumonia and influenza (PI), the Advisory Committee on Immunization Practices has recommended the use of 7-valent pneumococcal conjugate vaccine (PCV7), and incrementally expanded the target group for annual influenza vaccination of healthy persons, to ultimately include all persons ≥6 months of age without contraindications as of the 2010-2011 influenza season. We aimed to capture broader epidemiologic changes by looking at PI collectively.

METHODS

Using interrupted time series, we evaluated the changes in the rates of PI hospitalization and inpatient death across three periods defined according to the changes in vaccination policy. We assessed linear trends adjusting for seasonality, sex, and age group, allowing for differential impact across age groups. PI hospitalizations were defined as a principal diagnosis of PI, or a principal diagnosis of sepsis or respiratory failure, accompanied by a secondary diagnosis of PI.

RESULTS

Overall annual rates of PI hospitalizations and inpatient deaths declined by 95 per 100,000 (95% CI: 45-145) and by 4.4 per 100,000 (95% CI: 0.9-7.8), respectively. This translates to 295,000 fewer PI hospitalizations and 13,600 fewer PI inpatient deaths than expected based on the average rates from 1996 through 1999. PI hospitalizations dropped the most among seniors aged 65+ by 487 per 100,000, followed by children aged <2, by 228 per 100,000. PI inpatient deaths declined most among seniors aged 65+, by 25.3 per 100,000.

CONCLUSIONS

In this nationally representative study, PI hospitalizations and inpatient deaths decreased in U.S. between 1996 and 2011. There is a temporal association with the introduction and widespread use of pneumococcal conjugate vaccines, and the expansion of the target group for annual influenza vaccination to include all persons ≥6 months of age, while it is difficult to attribute these changes directly to specific vaccines used in this era.

Racial and Ethnic Disparities in Vaccination Coverage Among Adult Populations in the U.S

INTRODUCTION

Reducing racial/ethnic disparities in immunization rates is a compelling public health goal. Disparities in childhood vaccination rates have not been observed in recent years for most vaccines. The objective of this study is to assess adult vaccination by race/ethnicity in the U.S.

METHODS

The 2012 National Health Interview Survey was analyzed in 2014 to assess adult vaccination by race/ethnicity for five vaccines routinely recommended for adults: influenza, tetanus, pneumococcal (two vaccines), human papilloma virus, and zoster vaccines. Multivariable logistic regression analysis was performed to identify factors independently associated with all adult vaccinations.

RESULTS

Vaccination coverage was significantly lower among non-Hispanic blacks, Hispanics, and non-Hispanic Asians compared with non-Hispanic whites, with only a few exceptions. Age, sex, education, health insurance, usual place of care, number of physician visits in the past 12 months, and health insurance were independently associated with receipt of most of the examined vaccines. Racial/ethnic differences narrowed, but gaps remained after taking these factors into account.

CONCLUSIONS

Racial and ethnic differences in vaccination levels narrow when adjusting for socioeconomic factors analyzed in this survey, but are not eliminated, suggesting that other factors that are associated with vaccination disparities are not measured by the National Health Interview Survey and could also contribute to the differences in coverage. Additional efforts, including systems changes to ensure routine assessment and recommendations for needed vaccinations among adults for all racial/ethnic groups, are essential for improving vaccine coverage.