Influenza Vaccination Coverage Among Health-Care Personnel — 2011–12 Influenza Season, United States

Influenza vaccination of health-care personnel (HCP) is recommended by the Advisory Committee on Immunization Practices (ACIP) (1). Vaccination of HCP can reduce morbidity and mortality from influenza and its potentially serious consequences among HCP, their family members, and their patients (1–3). To provide timely estimates of influenza vaccination coverage and related data among HCP for the 2011–12 influenza season, CDC conducted an Internet panel survey with 2,348 HCP during April 2–20, 2012. This report summarizes the results of that survey, which found that, overall, 66.9% of HCP reported having had an influenza vaccination for the 2011–12 season. By occupation, vaccination coverage was 85.6% among physicians, 77.9% among nurses, and 62.8% among all other HCP participating in the survey. Vaccination coverage was 76.9% among HCP working in hospitals, 67.7% among those in physician offices, and 52.4% among those in long-term care facilities (LTCFs). Among HCP working in hospitals that required influenza vaccination, coverage was 95.2%; among HCP in hospitals not requiring vaccination, coverage was 68.2%. Widespread implementation of comprehensive HCP influenza vaccination strategies is needed, particularly among those who are not physicians or nurses and who work in LTCFs, to increase HCP vaccination coverage and minimize the risk for medical-care–acquired influenza illnesses.

For the Internet panel survey, two source populations were recruited through e-mails and pop-up invitations. Clinical professionals (e.g., physicians, nurses, and other health professionals [dentists, nurse practitioners, and physician's assistants]) were recruited from the current membership roster of Medscape, a web portal managed by WebMD Professional Services. Other HCP such as assistants, aides, administrators, clerical support workers, janitors, food service workers, and housekeepers were recruited for a health survey from SurveySpot, a general population Internet panel operated by Survey Sampling International that provides its members with online survey opportunities in exchange for nominal cash and rewards.* Among the 2,518 HCP who completed the screening questions and entered the two panel survey sites, 2,348 (93.2%) completed the survey.† Of those, 1,724 (73.4%) were clinical professionals, and 624 (26.6%) were other HCP.

Survey categories included demographics, occupation type, work setting, self-reported influenza vaccination, reasons for nonvaccination during the current influenza season, and employer vaccination policies. Based on their responses to the questionnaire, HCP from both Internet sources were divided into three groups for this analysis: physicians, nurses, and all other HCP with occupations listed on the screening questionnaire. Sampling weights were calculated based on each occupation type by age, sex, race/ethnicity, medical-care setting, and census region to be more representative of the U.S. population of HCP. Because opt-in Internet panel surveys are not random samples, statistical measures such as computation of confidence intervals and tests of differences cannot be performed.§

By occupation, influenza vaccination was most common among physicians (85.6%), followed by nurses (77.9%), and other HCP (62.8%) (Table). Vaccination coverage was 76.9% among HCP working in hospitals, 67.7% among those in physician offices, and 52.4% among those in long-term care facilities (LTCFs). By occupation and work setting, influenza vaccination was most common among physicians who worked in hospitals (86.7%) and lowest among other HCP who worked in LTCFs (50.2%) (Table). Among HCP working in hospitals that required influenza vaccination, coverage was 95.2%; among HCP in hospitals not requiring vaccination, coverage was 68.2%.

Coverage among HCP aged ≥60 years (75.7%) was higher than coverage for other age groups. Among racial/ethnic groups, coverage did not differ more than 5 percentage points. Vaccination coverage was higher among HCP with vaccination available at no cost on multiple days at their worksite (78.4%), compared with those not offered vaccination at no cost (48.4%). Overall, 496 (21.1%) of participating HCP reported being required to be vaccinated by their employers. Influenza vaccination was more common among those who reported that their employers promoted influenza vaccination (75.8%), compared with those whose employers did not promote influenza vaccination (55.8%) (Table).

Overall, 33.1% of HCP reported not receiving influenza vaccination. The three most common answers to a question asking for the main reason a participant did not get vaccinated for influenza were 1) a belief that they did not need it (28.1%), followed by 2) concern about vaccination effectiveness (26.4%) and 3) concern about side effects (25.1%).

Reported by

Sarah W. Ball, ScD, Deborah K. Walker, EdD, Sara M.A. Donahue, DrPH, David Izrael, MS, Abt Associates Inc., Cambridge Massachusetts. Jun Zhang, MD, Gary L. Euler, DrPH, Stacie M. Greby, DVM, Megan C. Lindley, MPH, Samuel B. Graitcer, MD, Carolyn Bridges, MD, Walter W. Williams, MD, James A. Singleton, PhD, Immunization Svcs Div, National Center for Immunization and Respiratory Diseases; Taranisia F. MacCannell, PhD, Div of Healthcare Quality Promotion, National Center for Emerging and Zoonotic Infectious Diseases, CDC. Corresponding contributors: Gary Euler, geuler@cdc.gov, 404-639-8742; Jun Zhang, jzhang5@cdc.gov, 404-718-4867.

Editorial Note

The overall HCP influenza vaccination coverage estimate from this Internet panel survey for the 2011–12 season was 66.9%, compared with previous CDC Internet panel estimates, from two surveys with varying methods, of 63.5% for the 2010–11 season (4) and 63.4% for the 2009–10 season (5) (Figure 1). Earlier estimates of influenza vaccination coverage levels in HCP based on the National Health Interview Survey (NHIS) were 10% in 1989, 38% in 2002 (6), and 49% in 2008 (7). In the Internet panel surveys for the three most recent influenza seasons, vaccination coverage was highest among physicians and nurses and lowest among all other HCP. From the 2009–10 season to the 2011–12 season, coverage increased among physicians from 80.5% to 85.6%, and among nurses from 68.5% to 77.9%. Coverage among all other HCP was similar from 2009–10 through 2011–12 in the Internet panel surveys.

For certain categories, vaccination coverage among HCP differed from 2010–11 to 2011–12, according to the Internet panel surveys. Coverage in physician's office settings increased from 61.5% during the 2010–11 season to 67.7% during the 2011–12 season, and coverage in hospitals increased from 71.1% to 76.9% (4). Among LTCFs, influenza vaccination coverage was lower in 2011–12 (52.4%), compared with 2010–11 (64.4%). The 2011–12 coverage in work settings other than hospitals, physician's offices, and LTCFs was higher (61.5%) than in 2010–11 (52.4%) (4) (Figure 2).

For the 2011–12 influenza season, vaccination coverage among physicians (85.6%) neared the Healthy People 2020 target of 90% (8). Among HCP work settings, hospitals were associated with the highest coverage, whereas coverage was lowest among HCP other than physicians and nurses working in LTCFs. Increased vaccination coverage was associated with employer vaccination requirements, employer promotion of HCP vaccination, and vaccination offered at no cost for multiple days.

These results indicate that targeted intervention and promotion programs developed for HCP groups other than physicians and nurses, and especially for those who work in LTCFs, might be important components in improving overall HCP vaccination coverage. Raising vaccination coverage of HCP working in LTCFs is especially important given that LTCF residents are at increased risk for serious influenza complications and that HCP vaccination might reduce the risk for death among LTCF residents (2,3). To increase vaccination coverage for HCP, each medical-care facility should develop a comprehensive intervention strategy that includes education and promotion to encourage vaccination and easy access to vaccine at no cost. Educational programs should include emphasis on vaccination effectiveness and its safety, knowledge of influenza transmission, and the benefits of HCP vaccination for staff, patients, and family.

The findings in this report are subject to at least five limitations. First, the sample was not selected randomly from the approximately 18 million HCP in the United States. The sample consisted of a much smaller group of several thousand volunteer HCP (a nonprobability sample) who had already enrolled in Medscape or SurveySpot. Second, all results are based on self-report and are not verified by employment or medical records. Third, the definition of HCP used in this Internet panel survey might vary from definitions used in other surveys of vaccination coverage. Fourth, occupation categories could not always be separated because of small sample sizes and questionnaire design or other limitations. Finally, the 2011–12 estimates might not be directly comparable to those made for previous influenza seasons using Internet survey panels and NHIS, because different methods of recruitment were used each year. Compared with the population-based estimates of NHIS, influenza vaccination among HCP from the Internet panel surveys differed (63.4% versus 57.5%) for 2009–10 (5). A similar difference (63.5% versus 55.8%) was observed for 2010–11 (4) (CDC, unpublished data, 2012).

A comprehensive intervention strategy that includes targeted education, promotion to encourage vaccination, and easy access to vaccination at no cost on multiple days can increase HCP vaccination coverage (1). Targeting undervaccinated HCP groups and regularly monitoring vaccination coverage are activities needed to stimulate increases in HCP influenza vaccination. CDC's National Healthcare Safety Network (NHSN), a longitudinal surveillance system, has introduced a module for reporting HCP influenza vaccination at the hospital level, based on the HCP influenza vaccination measure endorsed by the National Quality Forum (9). Beginning in January 2013, the Centers for Medicare & Medicaid Services will require acute care hospitals that they reimburse to report HCP influenza vaccination levels as part of the Hospital Inpatient Quality Reporting Program.¶ CDC will continue to use Internet panel surveys to monitor self-reported HCP vaccination coverage and reasons for nonvaccination across multiple occupation categories and work settings.

References

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8. US Department of Health and Human Services. Healthy people 2020. Objective IID-12.9. Washington, DC: US Department of Health and Human Services; 2012. Available at http://www.healthypeople.gov/2020/topicsobjectives2020/objectiveslist.aspx?topicid=23. Accessed September 24, 2012.
9. APIC. CDC alert: NHSN module for HCP influenza vaccination reporting available Sept. 14. Washington, DC: APIC; 2012. Available at http://www.apic.org/for-media/news-releases/article?id=b74a94cf-72be-44e3-a594-689327df860e. Accessed September 24, 2012.