Transcript Slide 1

Vaccination of
Adolescents: New
Frontiers
Andrew Kroger
National Center for Immunization and
Respiratory Diseases
National Assembly on Schoolbased Health Care (NASBHC)
May 16, 2007
Vaccine Research and
Development
Basic research, animal studies
Phase I: safety,
Immunogenicity(10-20)
Phase II: Dose ranging (20several hundred)
Phase III: safety, efficacy
(several hundred to several
thousand)
Biologics License Application
Vaccines of the Future
Cytomegalovirus
Human
immunodeficiency
virus
Herpes simplex virus
Group B
streptococcus
Challenges to New Vaccine
Development
Understanding the immune
response to natural infection not
complete
Humoral and cell-based immune
response important to
developing an effective vaccine
Need to be able to test efficacy –
often outcomes difficult to study
due to long latency
Cytomegalovirus
Herpesvirus
Latent virus with
reactivation
Infection is Common
Congenital CMV
Severe in patients
with Altered
Immunocompetence
CMV Vaccines
Candidates
• Live-attenuated and
subunit vaccines (Phase I)
• Vector vaccines (canarypox
virus vector)
Challenges
• Humoral and cellular
response critical
Human Immunodeficiency
Virus (HIV) Infection
1 million infected in U.S.
25% unaware of their infection
Progresses to Acquired
Immunodeficiency Syndrome
(AIDS)
HIV virus transmission –
sexual and percutaneous
HIV pathogenesis percutaneous and mucosal route
HIV Vaccine Trials Network
56 trials occurring in 25
sites worldwide
29 candidate vaccines
Strategies
•Recombinant vectors
•Prime-boost approach
HIV Vaccines
Challenges
•Effective animal models
for preclinical trials
•Determining appropriate
outcomes to measure
Herpes simplex virus (HSV)
Family
Herpesvirus
Reactivation
disease
HSV1: Cold sores
HSV2: Genital
herpes
HSV
Vaccine candidates
•Subunit vaccine (phase
II): efficacy in women
•Live attenuated (current
phase I)
Challenges
•Determining efficacy
Group B Streptococcus
Perinatal
transmission
Asymptomatic
colonization (21%
pregnant women)
Causes sepsis in
newborns
Generally treated
with antibiotics
during labor
GBS
Vaccines
•Pure polysaccharide
•Protein conjugate
vaccines (phases I, II)
Challenges
•Multiple serotypes
Link to the Jordan Report from NIP website
Vaccine-preventable
diseases and
adolescents: why so
many cases?
Pertussis
Pertussis Impact Among
Adolescents & Adults
Pneumonia (2%)
Rib fractures (1%)
Hospitalization (~1%)
Medical costs
Missed school and work
Impact on public health system
Loss of sleep; loss of consciousness
Weight loss
Why Adolescents & Adults
need Pertussis Vaccine
In 2003 pertussis vaccine levels in children 19-35
months highest ever
Pertussis cases continued to rise
2005 – 25,616 pertussis cases,
highest recorded since 1959
– 67% of cases - adolescent or adult
– Overall incidence is 8.7/100,000
– Infants < 6 months 160.8/100,000
Pertussis immunity wanes in 5-10 years
Pertussis Trends in the
U.S.
1994-2004 reported cases, 5x higher
2001-2005* - 109 pertussis-related deaths
88/109 or >80% who died were too young to
have completed a primary series of DTaP
Source of infection most often an older child
or adult in the household
*2001-15; 2002-22; 2003-18; 2004-16; 2005-38 CDC unpublished data
Why Pertussis in Adolescents?
Waning immunity
Improved diagnostics
Improved surveillance
Tdap Vaccine
Tdap vaccines licensed by FDA May
and June 2005
ACIP Recommendations for
adolescents in MMWR March 2006
ACIP Recommendations for adults in
MMWR December 2006
Pertussis Vaccines - Tdap
®
Boostrix
(GlaxoSmithKline)
– Licensed May 3, 2005
– Single dose
– Approved for persons 10-18 years of age
Adacel
®
(sanofi pasteur)
– Licensed June 10, 2005
– Single dose
– Approved for persons 11-64 years of age
Adolescent-Adult Pertussis
Vaccination Objectives
Primary
– Protect vaccinated adolescents
– Continue protection after completion of initial
series
Secondary
– Reduce B. pertussis reservoir
– Reduce pertussis incidence in other age groups
General Principles Use of
Tdap and Td
Tdap is preferred for
protection against
pertussis
Tdap is licensed for ONE
single dose at this time
Tdap Adolescent Recommendations
Adolescents 11-12 years of age should
receive a single dose of Tdap instead
of Td*
Adolescents 13-18 years with no Tdap
should receive one dose as a catch-up
booster instead of Td*
*if the person has completed the
recommended childhood DTaP vaccination
series, and has not yet received a Td booster
Persons >10 years with NO
History of Primary Series
Use 3 dose adult
schedule but give Tdap
for first dose of series
Preferred schedule
– #1 Tdap
– #2 Td – at least 4 wks after dose #1
– #3 Td – at least 6 mos after dose #2
Tdap Recommended Uses
Persons >10 yrs and adults who anticipate
or have close contact with infants <12
months of age should receive one dose of
Tdap
Tdap can be used for tetanus prophylaxis
wound management
Use Tdap for next routine booster dose even
if history of pertussis disease
HCP with direct patient contact, esp. if <12
months age. Interval can be 2 years
Tdap Uses in Pregnancy*
Safety data not available; registry is in progress
If tetanus and diphtheria protection needed,
give Td
If pertussis risk present, give Tdap
Pertussis risk in pregnancy = adolescents, pregnant
HCP, child care providers of infants <12 months or
vulnerable persons, living or working in area with
increased pertussis
Td and Tdap when vaccine should not be deferred to
post partum, administration in 2nd or 3rd trimester is
preferred
*See section 3-K in Adolescent Tdap ACIP Recommendations
Meningococcal
Disease
Schoeller T, Schmutzhard E. N Engl J Med. 2001;344:1372
Rates of Meningococcal
Disease* by Age, 11-30 y/o,
United States, 1991-2002
Rates per 100,000
ABCs
NETSS
2.5
2
1.5
U.S. Rate
1
0.5
0
11
13
15
17
* Serogroups A/C/Y/W135
19
21
Age (yr)
23
25
27
29
Risk Factors for Meningococcal
Disease in the United States
Deficiencies in the terminal
complement pathway
Functional or anatomic asplenia
HIV infection
Smoking
Passive exposure to smoke
Upper respiratory tract infection
Crowding
Meningococcal Disease
Among Young Adults, United
States, 1998-1999
18-23 years old
1.4 / 100,000
18-23 years old
not college student
1.4 / 100,000
Freshmen
1.9 / 100,000
Freshmen in dorm
5.1 / 100,000
Bruce et al, JAMA 2001;286;68893
Approved by FDA
January 2005
Meningococcal Conjugate
Vaccine
TM
Menactra (sanofi pasteur)
Quadrivalent (serogroups A, C, Y, W-135)
conjugated to diphtheria toxoid
Approved for persons 11-55 years of age
Schedule: 1 dose
Administered by intramuscular injection
Meningococcal Conjugate
Vaccine
Approved only for persons 11 through
55 years of age
Persons 2-10 years of age >55 years
at increased risk should receive the
meningococcal POLYSACCHARIDE
vaccine
Meningococcal vaccine is not routinely
recommended for persons 2-10
years of age or older than 55 years
who are not in a high risk group
Meningococcal Vaccine
Recommendations
Recommended for:
– all persons at the preadolescent visit (ages 1112 years)
– persons about to enter high school (age 15
years)
– college freshmen living in a dormitory
– other adolescents who wish to reduce their
risk for meningococcal disease
MMWR 2005;54(RR-7)
Meningococcal Vaccine
Recommendations
Recommended for certain
high-risk persons:
– military recruits
– certain research and laboratory
personnel
– travelers to and U.S. citizens residing in countries in which N.
meningitidis is hyperendemic or epidemicterminal complement
component deficiency
– functional or anatomic asplenia
– HIV infection (“should be considered”)
MMWR 2005; 54(RR-7);1-21
Meningococcal Conjugate
Vaccine (MCV) and GBS
MCV approved by FDA in January 2005
15 cases of GBS among 11-19 year olds within 6
weeks of MCV
FDA/CDC advisory issued September 30, 2005
No change in vaccine recommendations as of
October 20, 2005*
*except to avoid vaccination of persons with a history of
GBS who are not at increased risk of infection
Newsweek: 1 May 2006
Dubuque, Iowa
1956 Philadelphia
Why Mumps in Adolescents?
Highly communicable
Imperfect vaccine efficacy
Mumps Vaccine Efficacy
• 70-80% after one dose
• 90-95% after two doses
Therefore:
• 50-100 of 1,000 immunized persons
will be infected
• Of 100 people, 98 are immunized
 5 or 5% of the 98 get mumps
 2 unvaccinated get mumps
 5 of the 7 total who get mumps will be
immunized
Mumps Prevention
Immunization
– TWO doses for school age children
– Ensure adult immunity
– Healthcare workers need immunity!!
•HCWs need TWO doses MMR or proof
of immunity
Identify and isolate ill persons for ~ 9 days
– note location, date for epi-link
Identify and vaccinate susceptible contacts
Practice good hygiene
Adolescent Vaccination
Questions?