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Running head: PERTUSSIS: AN EMERGING INFECTIOUS DISEASE
Pertussis: An Emerging Infectious Disease
Jackie A. Wirth, RN
Ferris State University
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PERTUSSIS: AN EMERGING INFECTIOUS DISEASE
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Abstract
Emerging infectious diseases are those that are rising unexpectedly. Pertussis is an emerging
infectious disease that has reemerged over recent times. It is caused by the bacteria Bordetella
pertussis, which is a small Gram-negative coccobacillus that causes respiratory infection in
infants, young children, adolescents, and adults. It is often referred to as whooping cough
because of a characteristic cough with an inspiratory whoop sound. The infection was originally
discovered in the 16th century and remains a concern today. Pertussis is transmitted through
inhalation of the bacteria. The disease consists of four stages, incubation, catarrhal stage,
paroxysmal stage, and convalescent stage. The most accurate way to test for Pertussis infection
is a culture of the nasopharynx. A positive diagnosis of Pertussis warrants antibiotic treatment.
The recent increase in incidence is mainly due to the wane in vaccination immunity. Children
receive a series of DTaP vaccination during childhood and a TdaP booster injection as an
adolescent or adult. Vaccination is the primary form of prevention and new recommendations to
increase booster doses may be the only way to stop the emergence of Pertussis.
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Pertussis: An Emerging Infectious Disease
Emerging infectious diseases (EID) rise suddenly and unexpectedly. Stedman’s Medical
Dictionary (2006) defines an infectious disease as a “disease capable of being transmitted from
person to person, with or without actual contact” (Stedman’s Medical Dictionary, 2006, p. 970).
These diseases may be newly discovered or reemerging in nature.
Pertussis, also known as Whooping Cough is an infectious disease that has reemerged in
recent years. Since the 1980s, Pertussis has increased in the United States with a peak every two
to five years. It occurs equally in both genders, with most cases being reported in infants less
than one year of age. Another high incidence group are adolescents between 10 and 19 years old
(Carson-DeWitt, Davidson, Checchia, 2011). It was during the 16th century that Pertussis was
first recognized as a human acute respiratory disease. Bordet and Genjou identified the
etiological agent Bordetella pertussis in 1906 (Marzouqi, Richmond, Fry, Wetherall, & Mukkur,
2010). Bordetella pertussis is a small Gram-negative coccobacillus that causes respiratory
infection in infants, young children, adolescents, and adults. This paper will attempt to describe
Pertussis in depth, identify factors that promote the emergence of infection and a critical analysis
of current research findings on this reemerging infectious disease.
Pertussis is highly contagious and is transmitted through respiratory droplets when an
infected individual coughs (Paisley et al., 2012). Healthy individuals acquire infection by
inhaling the bacteria infected droplets that are expelled into the air when infected individuals
cough. After inhalation of the bacteria, individuals can be symptomless for 7-14 days, otherwise
known as the incubation period. During this time the bacteria are busy multiplying, trying to
penetrate the entire respiratory tract (Carson-DeWitt, 2011).
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B. pertussis has the ability to adapt, is a non-invasive respiratory pathogen, and localizes to
the tracheobronchial tree. It produces toxins and other determinants that promote the disease
process and weaken the immune system (Marzouqi et al., 2010). The bacteria attaches to cells
with cilia in the respiratory tract. Cilia sweep the respiratory tract clean of mucus, bacteria,
viruses, and other debris. They are hair-like projections and when Pertussis bacteria interfere
with their function, the cellular debris will accumulate. This causes respiratory tract irritation,
increasing mucus and cough (Carson-DeWitt et al., 2011).
There are four stages to the disease process of Pertussis, which may overlap at times. The
incubation period is symptomless and consists of 7-14 days after infection with Pertussis.
Infection persists after the incubation period with the catarrhal stage or as a mild upper
respiratory disease. Pertussis is highly contagious in this first stage. It may last for 10-14 days
and most of the time it is mistaken as an exceedingly heavy cold. Symptoms consist of teary
eyes, sneezing, fatigue, and poor appetite. Extreme runny nose or rhinorrhea is also a
characteristic symptom (Carson-Dewitt et al., 2011). Up to 90% of unvaccinated household
contacts will contract Pertussis during its first stage (Posfay-Barbe, 2012).
The paroxysmal stage begins with a characteristic whooping cough. The whoop sounds like
a sharp inspiration of air and is believed to occur due to respiratory tract inflammation, mucous,
narrowing airways and intense exhaustion. This may last for two to four weeks. Activity,
feeding, or crying may induce the paroxysms or spasms (Carson-Dewitt et al., 2011). The
second stage consists of a cough with vomiting and ends over several weeks with the
convalescent stage (Posfay-Barbe, 2012).
“The Center for Disease Control and Prevention case definition for pertussis surveillance is
defined as a patient with a cough of at least 14 days duration and at least one of the following:
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paroxysmal cough, inspiratory whoop, or posttussive vomiting” (Paisley et al., 2012, p. 142).
When Pertussis is suspected, the most accurate method to test for infection is by a nasal culture.
The healthcare provider uses a swab to obtain a specimen of mucus from the nasopharynx and
sends to the specimen to the medical lab for analysis. The bacteria B. pertussis can then be
identified by examination under a microscope (Carson-Dewitt et al., 2011). Once the lab results
determine B. pertussis is positively identified, a diagnosis can be made.
If a positive diagnosis is made, antibiotic treatment is needed. Azithromycin, clarithromycin,
erythromycin, and trimethoprim/sulfamethoxazole are all effective antibiotics to treat Pertussis
infection. Azithromycin is the preferred course of treatment in the United States. There is not
sufficient evidence to support the use of antihistamines, beta-agonists, or corticosteroids (Paisley
et al., 2012). Other home remedies such as rest and monitoring fluids to prevent dehydration
may help reduce complications. The most effective treatment is prevention. Disease incidence
was originally reduced by the development of effective vaccines.
Analysis of the evidence suggests that the main way to prevent Pertussis infection is mass
immunization. Due to the highly contagious nature of the bacteria, immunization before
infection is crucial in prevention. According to a study by Marzouqi et al., Development of
improved vaccines against whooping cough (2010), new vaccines need to be developed and
tested in humans because of the immune responses considered to be important to long term
response. In order to stop the reemergence of pertussis, the number of booster vaccinations in
both children and adolescents needs to be increased. Another option would be to develop a “live
attenuated B. pertussis vaccine that mimics natural infection with potential to induce longer-term
protection against whooping cough” (Marzouqi et al., 2010, p. 551).
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Pertussis is a classic infection of infants and young children who are not yet fully vaccinated
against the disease. There are many factors involved in the reemergence of Pertussis. According
to Marzouqi (2010), the factors are
better diagnosis, cyclic variation in disease patterns, waning of vaccine-induced immunity
in adolescents and adult over time due to the limited protection offered by the currently
used vaccines and loss of vaccine efficacy due to the emergence of new B. pertussis strains
overproducing pertussis toxin. (p. 544)
One of the factors associated with the emergence of Pertussis is wane in the current
vaccination. Due to decreased immunity among vaccinated adolescents and adults, Pertussis is a
reemerging disease that has been observed in those previously thought to have immunity
(Paisley, Blaylock, & Hartzell, 2012). DTaP is the vaccine that is given to children in a series of
five inoculations. The “acellular Pertussis vaccine contains one or more immunogens derived
from the B. pertussis organism” (Perry, Hockenberry, Lowdermilk, & Wilson, 2010, p. 983).
According to the Center for Disease Control and Prevention (2007), the first dose should be
given at two months of age, with subsequent doses following at four months, six months, 15-18
months, and four to six years of age (U.S. Department of Health & Human Services, 2007). A
societal factor that contributes to rising Pertussis rates is that some individuals choose to be
unvaccinated or refuse the DTaP vaccine for their children. This puts not only the unvaccinated
person at risk, but also those who are too young for the vaccine, endangering the community as a
whole. Communal vaccination is key to the prevention of Pertussis. A single booster dose of
diphtheria and reduced tetanus toxoids and accellular pertussis is recommended for individuals
11-64 years of age. The booster dose is called TdaP and is similar to DTaP (U.S. Department of
Health & Human Services, 2007). Vaccinated individuals are an important reservoir for infants
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and those without a complete series of vaccination. Infants are the most vulnerable to Pertussis
and have the highest risk for complication, including death (Paisley, et al., 2012). “Prompt
recognition and timely diphtheria and reduced tetanus toxoids and accellular pertussis (TdaP)
vaccination is crucial in adolescents and adults to curtail future outbreaks and complications in
vulnerable populations” (Paisley et al., 2012, p. 141).
Pertussis is an emerging infectious disease that was originally reduced in incidence due to
the development of effective vaccinations. It is caused by the bacteria B. pertussis, which is
highly adaptive and infectious. Respiratory droplets transfer the bacteria from person to person.
The infected person coughs, releasing bacteria in the air for healthy individuals to inhale. After
inhalation the bacteria, infection sets in. Four stages make up the disease process, with an
asymptomatic incubation period that can quickly infect others. Antibiotic treatment is needed
after a positive diagnosis is made. The best way to control the spread of disease is prevention
through mass vaccination. Vaccine effectiveness wanes after a certain number of years and due
to this factor, the incidence of Pertussis infection has risen. Other factors that have affected the
rise in Pertussis are better diagnosis and development of new strains of the disease.
Implementing the recommendation to increase the number of booster vaccines is one way that
should be considered in the fight against Pertussis. Vaccine effectiveness is key to stopping this
emerging infectious disease.
PERTUSSIS: AN EMERGING INFECTIOUS DISEASE
References
Carson-Dewitt, R., Davidson, T., Checchia, P. (2011). Whooping cough. Nursing Resource
Center. Retrieved from http://0-find.galegroup.com.libcat.ferris.edu/nrcx/infomark.go?
&source=gale&srcprod=NRCX&prodId=NRC&userGroupName=lom_ferrisu&tabID=
T001&docId=DB2979101835&type=retrieve&contentSet=GREF&version=1.0
Marzouqi, I., Richmond, P., Fry, S., Wetherall, J., & Mukkur, T. (2010). Development of
Improved vaccines against whooping cough. Human Vaccines, 6(7), 543-553.
Paisley, R. D., Blaylock, J., & Hartzell, J. D. (2012). Whooping Cough in Adults: An
Update on a Reemerging Infection. The American Journal of Medicine, 125(2), 141-143.
Perry, S. E., Hockenberry, M. J., Lowdermilk, D. L., & Wilson, D. (2010). Maternal Child
Nursing Care. Maryland Heights, MO: Mosby Elsevier.
Posfay-Barbe, K. M. (2012). Infections in paediatrics: old and new diseases. Swiss Medical
Weekly: The European Journal of Medical Sciences, 142, 1-10.
Stedman’s Medical Dictionary (28th ed.). (2006). Baltimore, MA: Lippincott Williams &
Wilkins.
U.S. Department of Health & Human Services: Center for Disease Control and Prevention.
(2007). Diptheria Tetunus & Pertussis Vaccines. Retrieved from http://www.immunize.
org/vis/dtap01.pdf
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