Pertussis, commonly known as whooping cough, is a highly contagious bacterial illness that causes a violent or uncontrollable cough and can lead to severe respiratory distress.1 Bordetella pertussis is a fastidious gram-negative coccobacillus that can readily spread from one person to another via droplets generated through coughing and sneezing.1 B pertussis localizes in the respiratory tract, where it releases toxins that damage the respiratory epithelial tissue.1
The effects of pertussis often cause significant morbidity and mortality, leading to high costs for families and healthcare facilities. The Centers for Disease Control and Prevention (CDC) reported 28,660 cases of pertussis in the United States in 2014.1 In our practice area in Brooklyn, the New York City Department of Health and Mental Hygiene released a report of 109 confirmed cases of pertussis between October 2014 and October 2015.2
An estimated 90% of unvaccinated people who live with someone who has pertussis will develop the disease.3 Prevention through immunization remains the best defense in the fight against pertussis. Vaccination not only decreases the chances of contracting the disease, it also helps protect people with contraindications to the vaccine and produces a form of community immunity.3
Pertussis has been around for decades and remains a public health concern. It is thought to be on the rise mostly due to dips in the use of childhood vaccines, leaving adolescents and adults vulnerable.4 In 2005, the Tdap vaccine was specifically formulated for adolescents and adults. Recommendations for the vaccine are as follows: a single dose for adolescents ages 11 to 18, adults 19 or older, and pregnant women in the third trimester of each pregnancy, regardless of vaccination history.5
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Despite widespread availability of the vaccine and national recommendations for use, fewer than 85% of adults have been vaccinated against pertussis.6 Research shows that underutilization of the vaccine is largely due to failure of healthcare providers to assess vaccination status, to educate about vaccinations, and to offer the vaccine to patients during routine visits.6
We sought to develop and implement an intervention process that would promote increased administration of pertussis vaccine in our practice setting.
The study took place in an outpatient community clinic in Brooklyn, N.Y. Subjects were selected during a routine visit at the clinic, based on their needs for the Tdap vaccine. We included all adults 18 to 65 years old who had not previously been vaccinated against pertussis. History of an allergic reaction to the vaccine or its components contraindicated participation.
The study was approved by an institutional review board after a full expedited review. The Health Belief Model was utilized as the theoretical framework. The design was a pretest-posttest.
Weekly data for the rate of vaccine administration was collected 4 weeks prior to the intervention. The intervention was conducted over 2 weeks. The CDC requires that if a vaccine is to be given, the patient receives information about its risks and benefits before administration. The CDC has published standardized information in the form of the Vaccine Information Statement (VIS). The VIS forms, written at a 5th grade level and available in multiple languages, were utilized.
The effectiveness of the education process was validated using the teach-back method. It was further evaluated using a seven-question evaluation questionnaire completed by all participants.
CDC-approved educational handouts were given to subjects to take home to review later and potentially share with family members, friends, neighbors or co-workers. Posttest data were collected 4 weeks later and analyzed by week.
We analyzed the data using descriptive statistics to perform an analysis of variance (ANOVA) as well as a chi-square test. The use of the pretest scores as covariates in the ANOVA was to reduce the error variance and eliminate systematic bias. The chi-square test, on the other hand, was used to determine whether the observed weekly data in the posttest differed significantly from what would be expected by chance. All analyses were conducted using the Smith Statistical Package.
The pre-test data found that 30 patients had been vaccinated in the 4 weeks prior to the intervention. The post-test data showed that 99 patients received the Tdap vaccine within the 4 weeks after the intervention. We performed ANOVA and chi-square to evaluate the statistical significance of the differences.
The result of the ANOVA indicated a p value of 0.009331, much less than preset alpha value of 0.05. This result confirmed that the outcome of the study was not due to randomness. Computation of the chi-square analysis with the observed and expected frequencies resulted in a value of 10.12.
Based on the chi square distribution table, with a degree of freedom of 3, a minimum value of 7.815 is needed to reject the null hypothesis at the 0.05 level of confidence. Since the chi-square value of 10.12 is much greater than the critical value 7.815, we concluded that the differences between the observed and expected data were too great to be attributed to chance (p < 0.05).
Although the data indicated a significant improvement in the vaccine's uptake, the results are far short of the Healthy People 2020 goal of 90% or higher coverage overall. The study had several limitations: The intervention process was limited to only 2 weeks. The data collection period was too short. The data collection was from a secondary source. And the facility ran out of the vaccine for 2 days during week 4 of post-data.
Future studies are recommended. These should have longer intervention process/data collection; should include daily manual extractions of the vaccine administration to ensure primary source of evidence and promote more reliability and validity;
and should maintain better coordination with the vaccine's ordering manager to ascertain adequate vaccine supply.
In the United States, pertussis is a notifiable disease at the state level. All healthcare providers are required by law to report any actual or suspected cases.7 Nurses and nurse practitioners have important roles in minimizing barriers to immunizations through vaccination education and administration.7
The cost of treating nosocomial exposure to B pertussis can lead to substantial disruptions and costs to the healthcare system.8 Reports about pertussis in healthcare settings, with difficulties of infection control and post-exposure prophylaxis associated with these outbreaks, remain of great concern.8 Healthcare facilities are, therefore, charged to obtain diagnostic testing; to report clinically suspect cases promptly to the health department; to promote appropriate droplet precautions; and to provide early treatment as well as post-exposure prophylaxis to prevent ongoing transmission.8
Education Can Prompt Action
The results of the study indicate that the educational intervention promoted a statistically significant increase in vaccine administration. The assumption that an educational process would be more effective in influencing health behaviors than a simple information message was proven accurate. We found a statistically significant relationship between the education process and the number of patients who accepted and received the vaccine in the 4 weeks after the intervention.
Clemaine C. Mitchell is a nurse practitioner at Caribbean House Health Center in Brooklyn, NY. Taisha Benjamin, a pediatrician, is the associate medical director of Caribbean House Health Center. Francisca Farrar is an NP and professor at Chamberlain College of Nursing.
1. CDC. Pertussis outbreak trends and prevention. http://www.cdc.gov/pertussis/outbreaks/trends.html
2. New York City Department of Health and Mental Hygiene. Pertussis in New York City. https://www1.nyc.gov/assets/doh/downloads/pdf/cd/2014/Pertussis%20Alert%20_10_16_15final.pdf
3. Feemster KA. Understanding the Pertussis Resurgence. Children's Hospital of Philadelphia. http://www.chop.edu/news/understanding-pertussis-resurgence#.V5-ghtIrKM8
4. Wendelboe AM, et al. Duration of immunity against pertussis after natural infection or vaccination. Pediatric Infect Dis J. 2007;24(5 suppl):S58-S61.
5. Advisory Committee on Immunization Practices. Recommended adult immunization schedule: United States, 2012. Ann Intern Med. 2012;156(3):211-217.
6. McGarry LJ, et al. Cost-effectiveness analysis of Tdap in the prevention of pertussis in the elderly. PLoS ONE. 2013;8(9):e67260. doi:10.1371/journal.pone.0067260
7. Spratling R, Carmon M. Pertussis: an overview of the disease, immunization, and trends for nurses. Pediatr Nurs. 2010;36(5):239-244.
8. Edwards KM, Talbot TR. The challenges of pertussis outbreaks in healthcare facilities: is there a light at the end of the tunnel? Infect Control Hosp Epidemiol. 2006;27(6):537-540.