infection control and hospital epidemiology
november 2007, vol. 28, no. 11
original article
Healthcare Workers’ Knowledge and Attitudes
About Pertussis and Pertussis Vaccination
William P. Goins, MD; William Schaffner, MD; Kathryn M. Edwards, MD; Thomas R. Talbot, MD, MPH
objective.
design.
setting.
To determine knowledge and attitudes about pertussis and pertussis vaccination among healthcare workers (HCWs).
Self-administered, Web-based survey.
Tertiary-care academic medical center.
participants.
tutional e-mail.
Medical center employees who participated in direct patient care were recruited to complete the survey through insti-
results. Of 14,893 potentially eligible employees, 1,819 (12%) completed the survey. Most respondents (87%) did not plan to receive
the pertussis vaccine. Intent to receive vaccination (which included recent history of vaccination) was associated with the following 4
factors: receipt of a physician recommendation for vaccination (odds ratio [OR], 9.01), awareness of Centers for Disease Control and
Prevention recommendations for pertussis vaccination for HCWs (OR, 6.89), receipt of encouragement to be vaccinated from a coworker
(OR, 4.72), the belief that HCWs may spread pertussis to patients and family (OR, 1.80). Two factors were negatively associated with intent
to receive vaccination: the presence of children in the HCW’s home (OR, 0.69) and employment as a nurse (OR, 0.59). Reasons cited by
those who did not intend to receive vaccination included lack of a personal recommendation for vaccination (78%), receipt of vaccination
as a child (51%), and perception that there was no significant risk for contracting pertussis (38%).
conclusions. Of the HCWs surveyed, only 13% intended to receive the pertussis vaccine. A perceived lack of recommendation for
vaccination and inaccurate conceptions about pertussis and pertussis vaccination were cited as reasons HCWs did not intend to be vaccinated.
Institutional pertussis vaccination campaigns should focus on the risks of healthcare-associated pertussis and new recommendations for
pertussis vaccination.
Infect Control Hosp Epidemiol 2007; 28:1284-1289
From 1994 through 2004, the incidence of pertussis in the
United States increased from 1.8 to 8.9 cases per 100,000
individuals. In 2004, there were 25,827 cases of pertussis reported—the highest number of cases since 1959—with adolescents and adults accounting for 67% of reported cases,
an increase of 20% from 1990.1 Healthcare workers (HCWs)
are at increased risk for acquiring Bordetella pertussis infection as a result of both contact with infected patients and
waning protection from either childhood pertussis vaccination or prior pertussis infection.2-4 Healthcare-associated outbreaks of pertussis have been recognized and reported in a
diverse range of healthcare facilities.5-13 Infected HCWs can
serve as sources of infection for other susceptible contacts,
including patients, other employees, and family members.12
Vaccination is an effective tool for the prevention of pertussis in adults.14 In 2005, there were 2 tetanus toxoid, reduced
diphtheria toxoid, and reduced antigen quantity acellular pertussis (Tdap) vaccines licensed for use in adolescents and
adults.15 In view of the increasingly recognized problem of
healthcare-associated B. pertussis infections, the Centers for
Disease Control and Prevention (CDC) Advisory Committee
on Immunization Practices recommended in 2006 that all
HCWs receive a single dose of Tdap vaccine to reduce the
risk of transmission of pertussis in healthcare institutions.16
In spite of the excellent vaccine efficacy and this recent recommendation, questions remain regarding whether HCWs
will choose to receive Tdap vaccine. This study was conducted
to examine the knowledge and attitudes of HCWs about pertussis and Tdap vaccine.
methods
Study Setting and Population
This study was conducted at Vanderbilt University Medical
Center (Nashville, TN), an 832-bed tertiary-care referral center, and affiliated healthcare facilities over a 6-week period
From the Department of Medicine, Division of Infectious Diseases (W.P.G., W.S., T.R.T.), the Department of Preventive Medicine (W.S., T.R.T.), and the
Department of Pediatrics, Pediatric Clinical Research Office (K.M.E.), Vanderbilt University, Nashville, Tennessee.
Received March 5, 2007; accepted June 11, 2007; electronically published August 27, 2007.
䉷 2007 by The Society for Healthcare Epidemiology of America. All rights reserved. 0899-823X/2007/2811-0011$15.00. DOI: 10.1086/521654
hcw s ’ attitudes and knowledge about pertussis
in September and October 2006. The medical center employs
15,193 people. Individuals were recruited through institutional e-mail to complete a self-administered, Web-based survey. Three hundred employees were not recruited because
they had opted out of receiving medical center communications by e-mail. The e-mail contained a single eligibility
question. Only those individuals who answered that they anticipated face-to-face or hands-on patient contact during the
upcoming year were eligible to complete the survey.
Study Design
The survey included items designed to capture participants’
intent to receive pertussis vaccine (response options were
“yes,” “no,” and “don’t know”), their attitudes about the
vaccine, their perceptions about pertussis disease, and their
demographic characteristics. Content validity was established
through an iterative process with experts in infectious diseases
and hospital epidemiology. Attitudes were assessed with a 5point Likert scale. The survey’s readability was at a sixthgrade level, as measured by the Flesch-Kincaid index. Optional enrollment into a drawing for a gift was offered as an
incentive for participation. Responses were anonymous. The
study protocol was approved by the Vanderbilt University
institutional review board.
Analysis
Differences in demographic characteristics and attitudes were
analyzed by intent to receive vaccination (which included
recent history of vaccination), by use of the Student t test
for age and the Pearson x2 test for categorical variables. Respondents who did not plan to receive the vaccine and respondents who were uncertain about their intent to receive
pertussis vaccination were combined into a single group (ie,
“no vaccination intent”). Categorical variables were recoded
as dichotomous outcomes for logistic regression analysis. Likert items were recoded as “strongly agrees” or “does not
strongly agree.” Factors significantly associated with intent to
receive vaccination on univariate analysis were then analyzed
using multiple logistic regression because of the potential
colinearity among some factors, particularly attitudes. Only
surveys that included responses for all items that were significant on univariate analysis were included in the multivariate analysis. Sensitivity analyses were performed by replacing missing data; we used the mean when the missing
datum was age and the most common response option to
replace missing data for categorical variables. All analyses
were conducted with Intercooled Stata, version 9.2 (Stata).
results
Subject Characteristics
A recruitment message was sent to 14,893 employees. Because
the number of employees who actually participated in direct
patient contact was unknown, an accurate number of eligible
1285
persons could not be determined. Additionally, nonrespondents could not be described and compared with respondents.
A total of 1,819 surveys were returned. The mean age of
respondents was 39 years, and 81% were female (Table 1).
Most respondents (1,583 [87%]) did not plan to receive
pertussis vaccine. Only 236 (13%) of the respondents reported that they had received the vaccine within the previous
year or planned to receive the vaccine. The reasons that individuals planned or did not plan to receive the vaccine are
listed in Table 2. Intent to receive vaccination was low among
all occupational groups, including physicians (22% of whom
intended to be vaccinated), nursing aides (18%), therapists
(14%), persons with other occupations (14%), technicians
and persons with other healthcare support occupations
(12%), nurse practitioners and physicians’ assistants (11%),
and nurses (9%). Compared with persons who did not intend
to be vaccinated, a significantly greater proportion of those
planning to be vaccinated reported contact with pediatric
patients (67% vs 57%; P p .009), and a significantly lower
proportion reported having children living at home (40% vs
47%; P p .045). Respondents in the 2 groups did not differ
significantly with respect to age, sex, presence of an underlying medical condition, percentage of time spent working
with patients, or primary location where patient care was
provided.
table 1. Demographic Characteristics of 1,819 Healthcare Workers Who Responded to a Survey About Pertussis
Characteristic
Age, mean Ⳳ SD, years
Female sex
Underlying medical condition presenta
Children present at home
Percentage of time spent working with patientsb
!25%
25%-50%
51%-75%
175%
Contact with pediatric patients
Occupationc
Nurse
Nursing aide
Physician
Other practitioner
Therapist
Patient Service
Other
Value
39.3 Ⳳ 11.2
1,446/1,781 (81)
200/1,700 (12)
834/1,797 (46)
305 (17)
253 (14)
270 (15)
963 (54)
1,048/1,788 (59)
717
123
205
105
78
175
382
(40)
(7)
(11)
(6)
(4)
(10)
(21)
note. Data are proportion (%) or no. (%) of respondents, unless otherwise indicated. Percentages are calculated on the basis of the number of
persons who responded to that survey question, rather than on the number
of surveys returned.
a
Diabetes mellitus, chronic lung disease (includes asthma, emphysema,
chronic obstructive pulmonary disease, and chronic bronchitis) chronic heart
disease, chronic kidney disease, or immune deficiency (includes lymphoma,
leukemia, human immunodeficiency virus infection, acquired immunodeficiency syndrome, receipt of radiation treatment, receipt of chemotherapy,
and receipt of chronic oral steroid treatment).
b
A total of 1,791 respondents answered this question.
c
A total of 1,785 respondents answered this question.
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infection control and hospital epidemiology
november 2007, vol. 28, no. 11
table 2. Reasons Cited by Healthcare Workers (HCWs) for Their Intentions Regarding Pertussis
Vaccination
Respondents
citing this
reason, %
Respondent group, reason
HCWs who planned to receive or had already received vaccination
I want to protect my patients from getting whooping cough
I want to protect my family from getting whooping cough
The vaccine prevents whooping cough
Getting the vaccine is convenient
Whooping cough is a severe disease
The CDC recommends that I get the vaccine
I have contact with high-risk patients
I am at significant risk of getting whooping cough
A physician recommended that I get the vaccine
Other
HCWs who did not plan to receive the vaccine
No one recommended that I get the vaccine
I already got the pertussis vaccine as a child
I am not at significant risk of getting whooping cough
I received a booster shot for tetanus and diphtheria within the last two years
I do not have contact with high-risk patients
Medications are available to treat whooping cough
Getting the vaccine is inconvenient
Other
The vaccine does not prevent whooping cough
I am concerned about a severe bad reaction to the vaccine
Whooping cough is not a severe disease
I am concerned about getting whooping cough from the vaccine
I am afraid of pain caused by shots
I am afraid of needles
I am concerned the vaccine will harm my child as I am pregnant or breastfeeding
88
83
80
80
77
74
74
48
42
25
78
51
38
27
27
25
17
17
13
13
9
7
6
5
4
note. Data are the percentage of total responses provided for each reason. CDC, Centers for Disease Control
and Prevention.
Knowledge, Attitudes, and Recommendations Received
Compared with respondents who did not intend to receive
pertussis vaccine, those reporting intent to be vaccinated were
more likely to strongly agree with the following statements:
“Whooping cough is a serious illness for children” (75% vs
65%), “Whooping cough is a serious illness for adults” (39%
vs 29%), “My work places me at significant risk of getting
whooping cough” (39% vs 20%), “I may spread whooping
cough to my patients or family” (50% vs 27%), “The vaccine
is safe” (51% vs 29%), and “The benefits of the vaccine outweigh the risks” (62% vs 32%) (Table 3).
Respondents in the 2 groups did not differ with respect to
a self-reported history of pertussis. Respondents who planned
to be vaccinated were more likely than those who did not
intend to be vaccinated to report receiving encouragement
to be vaccinated from a coworker (16% vs 2%), receiving a
physician recommendation for vaccination (34% vs 2%), and
awareness of CDC recommendations for pertussis vaccination
for HCWs (77% vs 23%).
Predictors of Intent to Receive Pertussis Vaccine
A total of 1,712 (94%) of the surveys included responses for
all 14 items included in the multiple regression model. The
outcome variable was intent to receive pertussis vaccine. The
results of the analysis are shown in Table 4. The analysis
identified 4 positive predictors of intent to receive the pertussis vaccine: receipt of a physician recommendation for
vaccination (odds ratio [OR], 9.01), awareness of CDC recommendations for pertussis vaccination for HCWs (OR,
6.89), receipt of encouragement to be vaccinated from a coworker (OR, 4.72), and belief that HCWs may spread pertussis to patients and family (OR, 1.80). Two negative predictors of intent to receive the pertussis vaccine were having
children at home (OR, 0.69) and employment as a nurse
(OR, 0.59). Sensitivity analyses did not alter the results
significantly.
discussion
Of the HCWs surveyed, most did not intend to receive the
pertussis vaccine. A perceived lack of recommendation for
vaccination and inaccurate conceptions about B. pertussis infection and pertussis vaccination were the most common
reasons cited for lack of intent to be vaccinated. Concerns
about the potential spread of pertussis were the most common reasons cited for intent to be vaccinated. Given the new
CDC recommendations, it is essential to examine attitudes
hcw s ’ attitudes and knowledge about pertussis
1287
table 3. Knowledge and Attitudes About Pertussis and Pertussis Vaccine, and Vaccination Recommendations Received, Among Healthcare Workers (HCWs) With Intent to be Vaccinated
Percentage of respondents
Who said
Who said
“strongly agree” “do not strongly agree”
or “yes”
or “no”
(95% CI)
(95% CI)
Survey statement
P
a
Attitudes
Whooping cough is a serious illness for children
Whooping cough is a serious illness for adults
My work places me at significant risk of getting whooping cough
I may spread whooping cough to my patients or family
The vaccine is safe
The benefits of the vaccine outweigh the risks
Vaccine recommendationsb
I have had whooping cough in the past
A coworker encouraged me to get the vaccine
A physician recommended that I get the vaccine
The CDC recommends pertussis vaccine for all healthcare workers
with direct patient contact
75
39
39
50
51
62
(69-81)
(32-45)
(33-45)
(44-56)
(44-57)
(55-68)
65
29
20
27
29
32
(63-67)
(27-31)
(18-22)
(25-29)
(27-32)
(30-34)
.002
.003
!.001
!.001
!.001
!.001
7 (4-10)
16 (11-21)
34 (28-40)
6 (5-7)
2 (1-3)
2 (2-3)
!.001
!.001
.446
77 (72-82)
23 (21-26)
!.001
note.
Data are the percentage of persons who responded to that statement. CDC, Centers for Disease Control and Prevention; CI,
confidence interval.
a
Five-point Likert scale.
b
Response options were “yes,” “no,” and “don’t know.”
and misconceptions about pertussis and pertussis vaccine.
These data should help craft a more successful pertussis vaccination campaign for HCWs.
Numerous studies have demonstrated misconceptions and
beliefs among HCWs that are associated with decreased acceptance of influenza vaccine, another vaccine that has been
recommended for HCWs. These studies demonstrated that
decreased acceptance of influenza vaccine by HCWs was associated with lack of recognition of the severity of the disease,
failure to recognize that HCWs are at increased risk of exposure to infection and may transmit infection to susceptible
patients, fear of adverse effects from the vaccine, and belief
that the vaccine is ineffective.17-27 Our observations are similar
to these findings.
This study has several limitations. It was conducted in a
single medical center. No media efforts to promote awareness
of healthcare-associated pertussis or new recommendations
for pertussis vaccination were conducted prior to this study.
table 4. Multiple Regression Analysis of Pertussis Vaccination Survey Responses Among Healthcare Workers With Intent to be Vaccinated
Question type, response
OR (95% CI)
P
9.01 (5.51-14.73)
!.001
6.89
4.72
1.80
1.50
1.43
0.99
0.87
0.75
(4.72-10.07)
(2.45-9.08)
(1.16-2.78)
(0.88-2.56)
(0.92-2.23)
(0.64-1.54)
(0.52-1.46)
(0.50-1.14)
!.001
!.001
1.37
1.24
1.11
0.69
0.59
(0.94-1.98)
(0.86-1.80)
(0.66-1.87)
(0.48-0.99)
(0.40-0.88)
a
Survey statement
A physician recommended that I get the vaccine
The CDC recommends pertussis vaccine for all healthcare workers
with direct patient contact
A coworker encouraged me to get the vaccine
I may spread whooping cough to my patients or family
The benefits of the vaccine outweigh the risks
My work places me at significant risk of getting whooping cough
Whooping cough is a serious illness for children
The vaccine is safe
Whooping cough is a serious illness for adults
Demographic question
Contact with pediatric patients
Greater than 75% of time spent in direct patient contact
Occupation: Physician
Children living at home
Occupation: Nurse
.009
.14
.12
.97
.60
.18
.10
.24
.68
.04
.009
note. Odds ratios (ORs) and 95% confidence intervals (CIs) are estimated from multiple logistic regression
adjusting for all factors listed above. Only factors that were significant on univariate analysis were included in
the multiple analysis.
a
To which respondent said “yes” or “strongly agree.”
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november 2007, vol. 28, no. 11
However, some medical centers may have already initiated
educational efforts, and the beliefs of HCWs in these centers
may differ. Because the interpretation of the phrase “face-toface or hands-on contact” by potential participants may vary,
we are unable to determine how many HCWs felt they were
eligible for the study. In addition, the exact number of persons
who received the recruitment e-mail is unknown. For these
reasons, an accurate response rate cannot be calculated. Furthermore, the study sample may not be representative of the
total medical center population. The analyses in this study
are exploratory, and no adjustment was made for multiple
comparisons. Finally, the provisional recommendation for
pertussis vaccination for HCWs was made 7 months prior to
the start of this study,28 but the recommendation was not
published until after the study was completed.16 Therefore, it
was felt that intention to be vaccinated was a more appropriate outcome measure than actual receipt of the vaccine.
Intent has been theorized, however, to be a predominant
determinant of behavior.29
Surprisingly, HCWs with children living at home were significantly less likely to report intent to receive the pertussis
vaccine. One possibility is that HCWs with vaccinated children may not recognize the need to receive the pertussis
vaccine to protect unvaccinated family members. Alternatively, a lack of knowledge could have led some HCWs to
worry that the vaccine would allow for potential transmission
of the bacterium to their children.
In conclusion, to achieve maximal vaccination coverage,
institutional pertussis vaccination campaigns should focus on
the risks of healthcare-associated pertussis and potential
transmission to others as well as new recommendations for
pertussis vaccination. In addition, educational efforts should
emphasize that protection from childhood pertussis vaccination wanes with time and that repeat vaccination as an
adult is necessary to decrease healthcare-associated transmission of pertussis. Additional studies are needed to document the proportion of HCWs who receive pertussis vaccine, the determinants of pertussis vaccine acceptance, and
the change in those determinants as a result of implementation of tailored vaccination campaigns.
acknowledgments
We thank Tom A. Elasy, MD, MPH, Department of Medicine, Vanderbilt
University (Nashville, TN), for assistance in the development of this survey.
Financial support. W.P.G. reports receiving grant support from the Vanderbilt-Sanofi Pasteur Healthcare Vaccinology and Epidemiology Training
Program, the Vanderbilt Health Services Research Training Program (grant
5T32 HS 013833), and the Agency for Healthcare Research and Quality.
Potential conflicts of interest. W.P.G. reports receiving support from Sanofi
Pasteur through an educational grant. All other authors report no conflicts
of interest relevant to this article.
Address reprint requests to William Goins, MD, Vanderbilt University,
A-2200 MCN, 1161 21st Avenue North, Nashville, TN, 37232 (william.goins@
vanderbilt.edu).
Presented in part: 17th Annual Scientific Meeting of the Society for Healthcare Epidemiology of America; Baltimore, Maryland; April 2007 (Abstract
301).
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