1. Pertussis Awareness And Prevention
W. Michael Brown, MD, FAAP
Director of Pediatrics
Associate Director Family Medicine Residency
Bayfront Medical Center
St. Petersburg, Florida

2. Pertussis Awareness and Prevention: Objectives
Increase awareness and prevention of pertussis in the United States
Educate health care professionals on epidemiology and diagnosis of pertussis
Discuss importance of pertussis immunization
Discuss important strategies for improving control of pertussis
The objectives of this program, as stated in the above slide, are to:
1) Increase awareness and prevention of pertussis in the United States; 2) Educate health care professionals on the epidemiology and diagnosis of pertussis; 3) Discuss the importance of pertussis immunization, and to review efficacy and safety data of pertussis vaccines; and 4) Discuss the implementation of important strategies for improving control of pertussis.

3. PERTUSSIS (WHOOPING COUGH)
Acute respiratory tract infection by Bordetella pertussis
highly communicable
80% secondary attack rates among susceptible persons
Significant morbidity and mortality in infants
Milder nonspecific upper respiratory tract infection in adolescents and adults
Difficult to diagnose
Referred to by the Chinese as “the cough of 100 days”
Pertussis, or whooping cough, is a highly contagious acute respiratory infection caused by Bordetella pertussis, a gram-negative aerobic bacillus. It is one of the most highly communicable of all infectious diseases, easily transmitted from one person to another via coughed aerosolized droplets.
The disease may occur at any age, but it manifests most severely in infants and young children, in whom it is potentially life-threatening. In adults and adolescents, pertussis is relatively mild; the only symptoms may be those of a minor, nonspecific upper respiratory tract infection, or there may be no symptoms whatsoever. Diagnosis is thus difficult in this age group. Infected adults and adolescents with mild disease constitute the reservoir for infection in infants and young children.
Edwards KM, Decker MD, Mortimer EA Jr. Pertussis vaccine. In: Plotkin SA, Orenstein WA, eds. Vaccines. Philadelphia, PA: WB Saunders; 1999:
Scott PT, Clark JB, Miser WF. Pertussis: an update on primary prevention and outbreak control. Am Fam Physician. 1997;56:

4. Prolonged Cough Illness in Adolescents and Adults Due to Bordetella Pertussis
Source
Locale
Year(s)
% of cough illnesses
Jackson et al
Seattle
15%
Robertson et al
New S Wales
26%
Mink et al
Los Angeles
Schmitt-Grohé et al
Germany
32%
Wright et al
Nashville
21%
Wirsing v Köenig et al
31%
Rosenthal et al
Chicago
Jansen et al
San Diego
17%
Nennig et al
San Francisco
12%
Strebel et al
Minn-St Paul
13%
Birbeback et al
Denmark
Vicent et al
Korea
50%
Gilberg et al
Paris
1999
52%
[Note: New slide provided by S. Barone]

5. Pertussis Disease Manifestations
Incubation period days (range )
Stages
Catarrhal: runny nose, sneezing, low-grade fever, mild cough
Paroxysmal: severe spasms of cough, thick mucus, whoops, vomiting, exhaustion
Convalescent: gradual recovery with less frequent & less severe coughing
Photograph courtesy of the WHO

6. Why Is Pertussis Increasing?
Ascertainment…awareness and better diagnostic tests
Incomplete immunization of children
Variable vaccine efficacy
Waning immunity
~ 15 years after active disease
~ 5-10 years after vaccination
Under diagnosis, especially in adolescents and adults
Lack of an adolescent/adult booster vaccine
UNTIL NOW

7. DECLINE IN VACCINE-PREVENTABLE DISEASE
Disease Maximum Cases %
cases in change
_____________________________________________________________________________________
Diphtheria 296,939 in %
Tetanus 1,560 in %
Pertussis 265,269 in %
Measles 894,134 in %
Paralytic polio 21,269 in %
3,100 died
_______________________ _____________________________________________________________
Mumps 152,209 in %
Rubella 57,686 in %
HIB ,000 prior to %
From Centers for Disease Control and Prevention. MMWR 2004

9. Efficacy of Acellular Pertussis Vaccines Randomized, Blinded Trials*
Study
Vaccine
Efficacy (%) (Confidence Interval)†
(WHO)†
Stockholm
Gustafsson L et al. N Engl J Med.
1996;334:
DAPTACEL™
85 (81-89)
Connaught DTP
48 (37-58)
Italy
Greco D et al. N Engl J Med.
1996;334(6):
Infanrix®
84 (76-89)
36 (14-52)
*Shows results for vaccines available in the United States for 3-dose infant immunization series; effects of any booster dose are not included.
†The definition closest to the standard WHO case definition (Edwards KM et al. In: Plotkin SA et al, eds. Vaccines. 1999; ).

10. Reported Pertussis Cases by Year United States, 1922 – 2000
300
Routine pertussis immunization begins
250
200
Cases (Thousands)
150
100 50
1922
1930
1940
1950
1960
1970
1980
1990
2000
Year
Source: CDC. Pertussis --- United States, MMWR 2002;51:73-76.

11. The Growing Disease Reservoir Increases Exposure to Pertussis
26,000
25,827
24,000
22,000
25,827
122%
20,000
18,000
All Patients
16,000
Children  4 yrs. of age
14,000
11,647
11,647
12,000
9,771
10,000
7,867
5,795
8000
7,580
73%
5,795
3,355
5,137
6000
7,288
4,570
4000
1,730
3,355
2000
1980
1990
1995
1999
2000
2001
2002
2003
2004

12. Reports of Pertussis in the U.S. Average Number of Cases / Year
3500
552%
490%
3000
2500
Average Number of Cases / Year
2000
1500
1000
500
<1 yr
1-4 yrs
5-9 yrs
10-19 yrs
20+ yrs
Centers for Disease Control and Prevention. MMWR. 2002;51:73-76; Güriş et al. Clin Infect Dis. 1999;28:
National Immunization Program, Bacterial Vaccine Preventable Diseases Branch. Pertussis Surveillance Report, August 6, 2004

13. …there are between ~800,000 and 3
…there are between ~800,000 and 3.3 million cases per year in the United States.

14. Estimated Duration of Immunity After Infection or Vaccination
Source of Immunity Duration Reference
Natural infection years Wirsing Von Konig, 1995
Whole-cell vaccine
UK years Jenkinson, 1988
Finland years He, 1994
Germany > 6 years Lugauer, 2002
Acellular vaccine
Italy years Salmaso, 2001
Germany > 6 years Lugauer, 2002
Wirsing Von Konig et al. Lancet ID 2002:2:

15. Consequences of Waning Immunity
Increased transmission of pertussis disease to unimmunized and underimmunized infants and children1
Considerable pertussis-related morbidity and economic cost in families2
Increased incidence of pertussis disease among adolescents and adults1,3
Key Point: Adults and adolescents who are not reimmunized are not only
susceptible to infection but also pose a significant risk to close contacts
of all ages, including infants who are too young to be vaccinated.
Notes:
Individuals who do become infected can then serve as a reservoir of infection for other susceptible people, including the unimmunized and underimmunized infants most at risk for severe illness.1
Pertussis disease is also associated with considerable morbidity and economic cost in families,2 which will undoubtedly increase with the incidence of the disease.
Since the immunity afforded by vaccines gradually decreases after vaccination,1 and adolescents and adults in the United States generally do not receive a pertussis booster, it is possible the incidence of pertussis disease in these age groups may continue to increase.1,3
References:
Edwards KM, Decker MD, Mortimer EA Jr. Pertussis vaccine. In: Plotkin SA, Orenstein WA, eds. Vaccines. Philadelphia, PA; 1999:
2. Lee LH, Pichichero ME. Cost of illness due to Bordetella pertussis in families. Arch Fam Med. 2000;9:
3. Centers for Disease Control and Prevention. Pertussis—United States, MMWR. 2002;51:73-76.
1. Edwards KM et al. In: Plotkin SA et al, eds. Vaccines. 1999;
2. Lee LH et al. Arch Fam Med. 2000;9:
3. Centers for Disease Control and Prevention. MMWR. 2002;51:73-76.

16. Reported Pertussis Cases Are the Tip of the Iceberg
Nationwide, an estimated 12% of pertussis cases are actually reported
Underreporting may be greatest among adolescents and adults
Reported
Atypical forms
Not Reported
Key Point: Pertussis is highly underreported—only 12% of cases are
actually reported. It is likely that underreporting may be greatest among
adults and adolescents.
Notes:
One study estimated that nationwide, only 12% of pertussis cases are actually reported. [Güriş 1999, pg 1235, col 2, para 1, line 1]
Due to a lack of typical pertussis symptoms such as whoop, underreporting may be higher among adolescents and adults than for young children. [Güriş 1999, pg 1235, col 2, para 1, lines 2-4]
Therefore, the reported cases form the tip of the iceberg. The majority of cases are not reported due to various reasons, such as atypical forms, wide disease variability, underconsultation, underdiagnosis, low physician awareness, and inconsistency in case definitions.
Reference:
Güriş D et al. Changing epidemiology of pertussis in the United States: increasing reported
incidence among adolescents and adults, Clin Infect Dis. 1999;28:1230.
Wide disease variability
Under- reporting
Underconsultation
Underdiagnosis
Low physician awareness
Inconsistent case definitions
Güriş et al. Clin Infect Dis. 1999;28:1230. 16

17. Pertussis Cases Reported in 2002 Each Dot Represents One Case
The total number of cases and incidence rate for each state represent provisional numbers, which may change as states report more cases for 2002
Source: Bacterial Vaccine Preventable Diseases Branch, National Immunization Program, CDC.
Sharp demarcation at state borders illustrates inconsistent reporting.

18. 75% Of Suspected Sources For Infant Pertussis Cases Were Family Members
Other
25%
Mom
32%
20% Other Adults
Grandparent 8%
Dad
15%
Sibling
20%
47% Mom or Dad
33% Other Children
Bisgard, K. et al. Ped Infect Dis J. 2004;23:

19. The Cycle of Pertussis Susceptibility Promotes Transmission & Disease
Unvaccinated or partially vaccinated infants: Susceptible
Break the Pertussis Cycle: Vaccinate
Reduce morbidity in all age groups
Reduce reservoir of Pertussis disease
Prevent transmission of Pertussis disease between adolescents and adults, and from adolescents and adults to infants
Primary vaccination: Protected
Susceptible adolescents and adults:
Reservoir of B pertussis
Booster vaccination: Prolonged protection
No additional booster: Immunity wanes
Supported by multiple publications. See notes

20. Pertussis: Clinical Presentation In Infants

21. Severe vs Mild Pertussis
More common in infants
Occurs in nonimmune individuals
Paroxysmal cough (>21 days’ duration) with heavy inspiration (whoops) accompanied by vomiting and gagging
Characteristic symptoms (eg, whoop) often absent1
An important mechanism of transmission to infants
Estimated to represent 21% to 26% of acute cough illness in adults2,3
Often unrecognized, underdiagnosed
1. Scott PT et al. Am Fam Physician. 1997;56:
2. Strebel P. Infect Med. 1996;13:S33-S41.
3. Edwards KM et al. In: Plotkin SA et al, eds. Vaccines. 1999;
* World Health Organization (WHO) definition.

22. Common Clinical Manifestations of Adolescent-Adult Pertussis
Cough 97%  3 weeks, 52%  9 weeks
Paroxysms  3 weeks in 73%
Whoop in 69%
Post-tussive emesis in 65%
Teens missed average 5 days of school; Adults missed average 7 days of work
Average 14 days of disrupted sleep
De Serres et al. J Infect Dis. 2000;182:174–9.

23. PERTUSSIS DEATHS BY AGE, UNITED STATES (1980-1999)

24. Pertussis Complications By Age

25. Diagnostic Laboratory Findings In Pertussis
Marked lymphocytosis with leukocyte counts often exceeding 50,000 cells/mm3
Generally afebrile with no elevation of ESR or other acute phase reactions
CXR with a “shaggy heart” produced by bilateral perihilar infiltrates, edema, and atelectasis
Culture of posterior NP swab may take 2 weeks, but negative cultures are common especially after 4 weeks of illness
Direct immunofluorescent assay of NP secretions had variable sensitivity and low specificity
Serologic tests to measure immunglobin antibody to pertusis toxin (IgG, IgM, IgA).
DNA by PCR of NP secretions is the most sensitive and rapid test but may not always be available
*Most cases of Pertussis are diagnosed clinically!

26. Period Of Communicability Of Pertussis-2 -1 1 2 3 4 5 6 7 8 9 10 11 12
Weeks of cough
Catarrhal stage
Paroxysmal stage
Convalescent stage
Cough onset
Period of communicability
Persons with pertussis are most infectious during the catarrhal period starting as early as one day of cough
Some individuals, such as infants who remain culture-positive for several weeks, may be infectious for a longer period

27. Diagnostic Laboratory Findings in Pertussis
Positive Culture
Catarrhal
Paroxysmal Stage
Convalescent 50
Lymphocyte Count (thousands) 30 10
1-2
2-5
5-12+
Time After Onset of Symptoms (weeks)
Adapted from Mortimer EA. In: Krugman’s Infectious Diseases of Children. 10th ed. Mosby Year Book, Inc; 1998:

28. The best site to obtain an appropriate clinical specimen is the posterior nasopharynx, either by aspiration of nasopharyngeal secretions or by insertion of a swab applicator into the posterior nasopharynx.1
Samples taken from nasal discharge or by swabbing the throat and tonsils are inadequate.2
Polymerase chain reaction (PCR) is emerging as the diagnostic method of choice on the basis of studies showing it to be more specific and sensitive than culture.3,4
Serologic testing is not standardized and because of a lack of association between antibody levels and immunity to pertussis, results are difficult to interpret.3,4
Direct fluorescent antibody (DFA) can yield rapid results but has disadvantages of variable sensitivity and specificity.1
References:
1. CDC. Epidemiology and prevention of vaccine-preventable diseases (The Pink Book), 7th ed. US
Department of Health and Human Services. 2002: Available at
Accessed March 13, 2005.
2. Murphy T, Bisgard K, Sanden G. VPD Surveillance Manual, Chapter 2. Diagnosis and
laboratory methods. June 2000;
3. Chia JH, Su LH, Lin PY, et al. Comparison of multiplex polymerase chain reaction, culture, and
serology for the diagnosis of Bordetella pertussis infection [abstract]. Chang Gung Med J.
2004;27(6):
4. Wright SW. Pertussis infection in adults. South Med J. 1998;91(8):

29. Serology 3 weeks or longer IFA never
Diagnosis
Culture weeks cough
PCR
Serology weeks or longer
IFA never

30. TREAMENT OF PERTUSSIS
Infants younger than 6 months generally require hospitalization
Antibiotic Therapy:
Erythromycin 40 to 50 mg/kg/day given QID x 14 days
Azythromycin 10 to 12 mg/kg/day given Qday X 5 days
Clarithromycin 15 to 20 mg/kg/day given BID X 7 days
Bactrim or Septra 8 mg TMP/ 40 mg SMX per kg per day in two divided doses for 14 days if allergic to macrolides
*Treatment with antibiotics does not effect duration or severity of clinical course
Cough suppressants
MMWR Jan. 2005
Pertussis is most common among infants less than a year old, but anyone can get this disease. Pertussis can be hard to diagnose in very young infants, teens and adults because their symptoms often look like a cold with a nagging cough. However many different forums provide an avenue for transmission:
Adolescents acquiring pertussis from community and household contacts
School age or daycare children transmitting pertussis back to adults
The disease ranges from asymptomatic to severe however adolescents and adults with pertussis are more likely to have milder illness (I.e. and illness resembling and upper respiratory infection or acute cough illness without paroxysms, whoop, or post-tussive vomiting).1 Adults and adolescents can then transmit pertussis to their young infants who are at the highest risk of morbidity and mortality.
1 Cherry JD. Epidemiological, clinical, and laboratory aspects of pertussis in adults. Clin Inf Dis 1999; 28 (Suppl 2): S112-7.

31. Antigenic Components of B pertussis
FIM
Pertussis toxin (PT), also known as “lymphocytosis-promoting factor” (systemic action)
Filamentous hemagglutinin (FHA)
Pertactin (PRN) or 69 kD* protein
Fimbrial agglutinogens (FIM) (1-4 serotypes)
FHA PT
PRN
*kD = kilodalton.
Edwards KM et al. In: Plotkin SA et al, eds. Vaccines. 1999;

32. Diphtheria, Tetanus, and Acellular Pertussis Vaccines
Currently licensed in US
Tripedia®
Infanrix®*
Daptacel™
Boostrix™
Adacel®
Indicated Age Group
Infants/ Children†
Adolescents‡ (10-18 years)
Adults/ Adolescents‡ (11-64 years)
Antigenic
Components§ PT (µg) FHA (µg) PRN (µg) FIM (µg) D (Lf) T (Lf)
— — 6.7 5
— 25 10
— 2.5 5

33. Comparison of Tdap Vaccines
Adacel Boostrix
Company Sanofi GSK
Age
Efficacy 21d % %
7d % %
Components (fimbrae)
Diphtheria LF

34. The Adacel Program in Newfoundland
Replaced Td in 1999 school year
Adacel delivered in a Grade 9 (14 year olds) school-based program
Approximately 25,000 doses given by June 2004

35. Incidence of Pertussis in Newfoundland, 1993-200370 60
Introduction of adolescent dTaP5 50 40
Incidence per 100,000 Population 30
**** Pertussis outbreak confined to persons not immunized with dTaP5 20 10
****
Time Periods
CCDR Notifiable Disease Annual Summaries

36. Pertussis Incidence and Vaccine Use, 1993 – 2004 Canada’s Northwest Territories
Switch to Pentacel
Adacel begun 12 10 8
Average Yearly Cases / 10,000 6 4 2
Time Periods
Kandola, K. Abstract in Can J Infect Dis Med Microbiol. 2004;15:351. Manuscript in preparation.

37. United States Licensure Trial: Summary of Immunogenicity
Key point: Seroprotection rates for diphtheria and tetanus were comparable with
the Tdap and Td vaccines.
Notes:
This slide presents seroprotection achieved one month post vaccination with the Tdap and Td vaccines in adolescents and adults in a pivotal US trial.
Td 506 was a Phase 3, multicenter, randomized, double-blind trial conducted in the United States in adolescents (11-17 years) and adults (18-64 years) comparing the safety and immunogenicity of Tdap (Adacel™) and Td.
In adolescents, the diphtheria seroprotection rates were equal99.8% with Tdap and Td; as were the tetanus seroprotection rates which were 100%.
In adults, the diphtheria seroprotection rates were 94.1% and 95.1% with Tdap and Td, respectively. The tetanus seroprotection rates were 100% and 99.8% with Tdap and Td, respectively.
For diphtheria, the seroprotection rates among adults increased equally by 50% with both vaccines. Among adolescents they increased by 38% and 41% with Tdap and Td, respectively.
For tetanus, the seroprotection rates among adults increased by 2.7% and 4.1% with Tdap and Td, respectively. Among adolescents they increased by 0.4% and 0.8% with Tdap and Td, respectively.
Reference:
Data on file, Td 506 Aventis Pasteur Limited, Toronto, Canada.
Pre
Post
Diphtheria
Tetanus
Data reported for sera collected one month after vaccination.
Data on file, Td 506, Aventis Pasteur Limited, Toronto, Canada.

38. United States Licensure Trial: Summary of Solicited Systemic Reactions
Key Point: The incidence of systemic adverse reactions was comparable
following Tdap and Td vaccine administration. For both Tdap and Td
vaccines, headache is the most common reaction reported among adults
and adolescents.
Notes:
This slide presents the most common systemic adverse events observed after Tdap and Td vaccine administration in adolescents and adults in a large scale US safety and immunogenicity trial (Td506).
This trial was a Phase 3, multicenter, randomized, double-blind trial conducted in the United States in adolescents (11-17 years) and adults (18-64 years) comparing the safety and immunogenicity of Tdap (Adacel™) vs Td.
The adverse events observed with Tdap were comparable to those observed with Td vaccine.
The most common systemic reaction, among both adolescents and adults was headache, with an incidence of 44% for Tdap and 40% for Td in adolescents.
Other common systemic reactions included fever, body ache/weakness, tiredness, sore/swollen joint, and chills.
Severe systemic reactions were uncommon: the most common, headache, was reported in 1.96% of adolescents and 2.77% of adults in Tdap vaccine recipients.
Severe occurrences of all other systemic reactions occurred in <2.00% of adolescents and <2.37% of adults in Tdap recipients.
Reference:
Data on file, Td 506, Aventis Pasteur Limited, Toronto, Canada.
Fever
Headache
GeneralizedBody Ache
Tiredness
Sore Joints
Chills
Data collected from days 0-14.
Data on file, Td 506, Aventis Pasteur Limited, Toronto, Canada.

39. United States Licensure Trial: Summary of Solicited Local Reactions
Adolescents = years. Adults = years.
Key point: The incidence of local adverse events in the first 3 days after vaccination is
similar between Tdap and Td vaccines for both adults and adolescents, and these
reactions were well-tolerated.
Notes:
This trial was a Phase 3, multicenter, randomized, double-blind trial conducted in the United States in adolescents (11-17 years) and adults (18-64 years), comparing the safety and immunogenicity of Tdap (Adacel) vs Td.
Localized reactions of pain, swelling, and redness or erythema are common adverse reactions observed at the injection site for both Tdap and Td vaccine recipients and were comparable with both vaccines.
For both age groups, local pain was the most common reaction.
The incidence of any pain was slightly higher in adolescents receiving Tdap than Td (78% vs 71%); this difference is due to a slight increase in reports of mild pain among Tdap recipients. Comparable rates of local pain were reported in adults receiving Tdap and Td vaccines.
Overall Tdap vaccine was well-tolerated in both adolescents and adults; injection site erythema, swelling, and pain were brief in duration and tended to be of mild or moderate intensity.
Reports of severe local reactions were uncommon.
The severity data is as follows:
Severe erythema in adolescents: Tdap vs Td (6.04% vs 5.34%); in adults: Tdap vs Td ( 6.18% vs 4.81%).
Severe swelling in adolescents: Tdap vs Td (6.38% vs 5.46%); in adults: Tdap vs Td (5.77% vs 5.53%).
Severe pain in Adolescents: Tdap vs Td (1.45% vs 0.64%), in adults: Tdap vs Td (1.12% vs 0.89%).
Reference:
Data on file, Td 506, Aventis Pasteur Limited, Toronto, Canada.
Severe Erythema*
Erythema
Severe Swelling*
Swelling
Severe Local Pain†
Local Pain
No significant difference was observed between Tdap and Td recipients for any safety parameters measured with the exception of pain in adolescents which was marginally more frequent in Tdap recipients.
Data collected from days 0-3.
*≥35 mm; †Severe local pain: incapacitating, unable to perform usual activities, may have/or required medical care or absenteeism.
Data on file, Td 506, Aventis Pasteur Limited, Toronto, Canada.

40. Adequacy, Efficacy, & Safety Data for Tdap Vaccines
Age Indications: Adacel years, Boostrix years
Both vaccines met all agreed non-inferiority criteria
For Diphtheria and Tetanus antigens, at least as immunogenic as US – licensed Td vaccines
Pertussis booster response induced an immune response at least as immunogenic as Daptacel and Infanrix
Can be used concomitantly with other vaccines
Safety profile comparable to US-licensed Td Vaccine

41. FDA Vaccine Advisory Committee
Unanimous vote March 2005
Adacel safe and effective age years of age
Boostrix safe and effective years of age
Licensure… May, June 2005
CDC ACIP
July yr Universal Immunization, catch up 5 yrs from last Td Oct Universal Adult Immunization,10 yrs from Td

42. Rationale for Vaccinating Adolescents and Adults: Bordetella Pertussis Reservoirs
Adolescents and Adults Are Primary Sources for Infant Transmission
Health Care Providers
Most hospital outbreaks of pertussis disease involve transmission from health care workers to pediatric patients1
Adults/Parents
In Chicago, young mothers with a cough >7 days were shown to be a significant source of pertussis disease transmission to their young infants2
Grandparents
In 15% of families, an adult patient was identified as the source of infection for other household members. Fifteen percent of these adults were grandparents or great-grandparents of an affected child3
Adolescents/Siblings
For 27% of infants hospitalized with pertussis disease in London between 1998 and 2000, an older, fully vaccinated sibling was the source of infection4
Key Point: Identification and vaccination of the adult B pertussis reservoirs, such as
healthcare providers, parents, grandparents, and siblings are essential to preventing
the transmission of the disease to infants.
Young infants are at highest risk for severe complications from pertussis as they are too young to be immunized. Certain adolescent and adult population groups who serve as pertussis reservoirs should be vaccinated.
Health care workers: Most hospital outbreaks of pertussis disease involve transmission from health care workers to pediatric patients.1 [Sheretz 2001, pg 1, col 1, para 3, lines 6-10]
Adults/parents: A study assessing risk factors for pertussis among young infants during a pertussis outbreak in Chicago in 1993 found that young mothers with cough >7 days were shown to be a significant source of pertussis disease transmission to their young children.2 [Izurieta 1996, pg 503, abstract, lines 11-13]
Grandparents: A 2-year study assessing the symptoms and complications of pertussis in adults showed that in 15% of cases, an adult was the source of infection for other household members. Fifteen percent of these adults were grandparents or great-grandparents of the affected child.3 [Postels-Multani 1995, pg 140, col 2, para 5, lines 5-6; pg 141, col 1, para 1, lines 5-7]
Adolescents/siblings: For 27% of infants hospitalized with pertussis disease in London between 1998 to 2000, an older, fully vaccinated sibling was the source of infection.4 [Crowcroft 2003, pg 802, abstract, para 3, lines 8-9]
References:
1. Sherertz RJ, Bassetti S, Bassetti-Wyss B. “Cloud” health-care workers. Emerg Infect Dis. 2001;7:
2. Izurieta HS, Kenyon TA, Strebel PM et al. Risk factors for pertussis in young infants during an outbreak in Chicago in Clin Infect Dis. 1996;22:
3. Postels-Multani S, Schmitt HJ, Wirsing von Konig CH, et al. Symptoms and complications of pertussis in adults. Infection. 1995;23:
4. Crowcroft NS, Booy T, Harrison T et al. Arch Dis Child. 2003;88:
1. Sheretz et al. Emerg Infect Dis. 2001;7:
2. Izurieta et al. Clin Infect Dis. 1996;22:
3. Postels-Multani et al. Infection. 1995;23:
4. Crowcroft et al. Arch Dis Child. 2003;88:

43. Recommendations of the ACIP (CDC) for the use of Tdap vaccines:
Advisory Committee On Immunization Practices (ACIP) Recommendations For Tdap Vaccine In Adolescents
Recommendations of the ACIP (CDC) for the use of Tdap vaccines:
Adolescents 11 to 12 years of age be given Tdap in place of the Td booster currently being used
Tdap vaccine should be given to adolescents 13 to 18 years who missed the 11 to 12 year dose of Td
Adolescents 11 to 18 years of age who have already been vaccinated with Td are encouraged to receive a dose of Tdap to further protect against pertussis
Adolescents can and should receive Tdap and the meningococcal conjugate vaccine (menactra) at the same visit

44. ACIP Recommendations for Tdap Vaccine Use in Adults
Adults who have not received a Td immunization during the last 10 years should receive a single dose of Tdap Vaccine
Those not previously given Tdap vaccine may be given Tdap vaccine at shorter intervals (< 10 years) following last Td immunizations in settings of wound management and increased risk (including pertussis outbreaks and contact with infants
Adults who anticipate having close contact with infants (ie: parents, healthcare workers and daycare workers) should receive a single dose of Tdap vaccine to protect against pertussis if they have not received Tdap vaccine. Ideally these adults should receive Tdap vaccine at least one month before beginning close contact with infants

45. Other ACIP Recommendations for Adult Tdap Use
Women should receive Tdap vaccine immediately post partum if not previously immunized
Women are encouraged to receive Tdap vaccine before conception
Tdap vaccine is encouraged over Td vaccine in the wound care setting for those who have not previously received Tdap vaccine
Pregnancy is not a contraindication to Tdap and may be considered in the 2nd and 3rd trimester

46. ACIP Recommendations for Tdap Use In Healthcare Workers
There are 8-10 million workers employed in hospital and ambulatory settings.
The risk of contracting pertussis from healthcare workers is nearly 2 times greater than the general population.
For each decade the immunization of healthcare workers could prevent as many as 100, 000 cases of pertussis and save up to $151 million in direct and indirect costs.
Therefore it is recommended that all healthcare workers and anyone who works in a healthcare setting receive Tdap.

47. Strategies to Control Pertussis…
Improve immunization coverage
Ensure immunization of all appropriate infants
Prevent mild disease
Improve surveillance and reporting
Implement Tdap vaccines for adolescents and adults
Eliminate reservoirs of infection in general population
Reduce transmission to vulnerable infants

48. SUMMARY
Epidemiology of pertussis disease has changed with the spectrum of illness shifting to a milder form in all age groups
B. pertussis infections in the adolescent and adult populations are common and endemic accounting for more of the disease seen today
Immunity after natural infection or vaccinations is not life long and wanes rapidly after 5 – 8 years
Pertussis acounts for up to 25% of acute cough illnesses in the adolescent and adult populations
The adolescent and adult populations serve as a major resevoir of disease transmission to the young infant population
Immunizing the infant population on time and implementing a booster vaccine program in the adolescent and adult populations will have the greatest impact on decreasing the amount of disease seen

49. …a universal program of adolescent and adult boosters would decrease the circulation of B pertussis… and possibly could lead to the elimination of the organism…

50. Questions