IMMUNIZATIONS

1
IMMUNIZATIONS
2
DEFINITION

• Immunization is the process of inducing immunity
  artificially by either vaccination
• ( active immunization ) or administration of
  antibody ( passive immunization ).
• ACTIVE IMMUNIZATION
• Stimulates immune system to produce antibodies
  and cellular immune responses that protect
  against infectious agent.

3

• PASSIVE IMMUNIZATION
• Provides temporary protection through
  administration of exogenously produced antibody
  such as immune globulin.
• Also occurs naturally through transplacental
  transmission of antibodies to a fetus.

4

• Vaccine A product of weakened or killed
  microorganism (bacterium or virus) given for the
  prevention or treatment of infectious diseases
• Toxoid A modified bacterial toxin that has been
  made nontoxic but retains the capacity to
  stimulate the formation of antitoxin.

5

• The major constituents of vaccines
• 1. Active immunizing agent
• Single antigen tetanus , diphtheria toxoid
• Complex antigens live viruses,killed bacteria
• 2. Suspending fluid
• Sterile water or saline
• Tissue culture fluid egg Ag, gelatin
• 3. Preservatives , stabilizers , antibiotics
• Added to prevent bacterial growth / stabilize
  Ag
• Thiomersol mercurial subs.
• Neomycin , streptomycin

6

• 4. Adjuvants
• Aluminium salt added to enhance immune
• response
• Esp. vaccines with inactive microorgs
• eg. Hep B , Diph Tet toxoids

7
(No Transcript)
8

• VACCINES ON SCHEDULE
• 1. Hep B Hepatitis B( inactivated recombinant)
• 2. DTaP Diphtheria Tetanus toxoid and
• acellular pertussis vaccine (
  inactive)
• 3. DT Td. Diphtheria Tetanus toxoid
• 4. Hib Haemophilus influenzae b
• Polysaccharide protein conjugate
• 5. IPV Inactivated poliovirus vaccine
• 6. PCV7 Pneumococcal conjugate vaccine
• 7. 23PS Pneumococcal polysaccharide

9

• 8. MMR Measles mumps rubella live vaccine
• 9. Varicella Chicken pox live vaccine
• 10. Influenza Inactivated vaccine
• 11. Hepatitis A Inactivated vaccine

10
Simultaneous Administration
General Rule
There are no contraindications to simultaneous
administration of any vaccines.
11
Spacing of vaccine combinations not given
simultaneously
12
Interference Between Live Virus Vaccines
Separated by lt28 days

• Retrospective cohort study of 115,000 children
  vaccinated in 2 HMOs during January 1995 through
  December 1999
• Risk of breakthrough varicella 2.5 times higher
  if varicella vaccine given lt30 days following MMR
• No increased risk if varicella vaccine given
  simultaneously or gt30 days after MMR

MMWR 200150(47)1058-61
13
Intervals Between Doses
General Rule
Increasing the interval between doses of a
multi-dose vaccine does not diminish the
effectiveness of the vaccine. Decreasing the
interval between doses of a multi-dose vaccine
may interfere with antibody response and
protection.
14
Minimum Intervals and Ages
Vaccine doses should not be given at intervals
less than the minimum intervals or earlier than
the minimum age
15
Violation of Minimum Intervals or Minimum Age

• ACIP recommends that vaccine doses given up to
  four days before the minimum interval or age be
  counted as valid
• Immunization programs and/or school entry
  requirements may not accept all doses given
  earlier than the minimum age or interval

16
Extended Interval Between Doses

• Not all permutations of all schedules for all
  vaccines have been studied
• Every study of extended intervals have shown no
  significant difference in final titer
• It is not necessary to add doses or restart the
  series because of an extended interval between
  doses

17
(No Transcript)
18
Vaccine Adverse Reaction

• Adverse reaction
• extraneous effect caused by vaccine
• "side effect"
• Adverse event
• any event following a vaccine
• may be true adverse reaction
• may be only coincidental

19
Vaccine Adverse Reactions

• Local
• pain, swelling, redness at site of injection
• common with inactivated vaccines
• usually mild and self-limited

20
Vaccine Adverse Reactions

• Systemic
• fever, malaise, headache
• nonspecific
• may be unrelated to vaccine

21
Live Attenuated Vaccines

• Must replicate to produce immunity
• Symptoms usually mild
• Occur after an incubation period(usually 7-21
  days)

22
Vaccine Adverse Reactions

• Allergic
• due to vaccine or vaccine component
• rare
• risk minimized by screening

23
Contraindication

• A condition in a recipient which greatly
  increases the chance of a serious adverse event.

24
Precaution

• A condition in a recipient which may increase the
  chance or severity of an adverse event, or
• May compromise the ability of the vaccine to
  produce immunity.

25
Contraindications and Precautions
Permanent contraindications to vaccination

• severe allergy to a prior dose of vaccine or to
  a vaccine component
• encephalopathy following pertussis vaccine

26
Contraindications and Precautions
ConditionAllergy to Component Encephalopathy Preg
nancy Immunosuppression Severe illness Recent
blood product
Live C --- C C P P
Inactivated C C V V P V
Ccontraindication Pprecaution Vvaccinate if
indicated
27
Invalid Contraindications to Vaccination

• Mild illness
• Antibiotic therapy
• Disease exposure or convalescence
• Pregnancy in the household
• Breastfeeding
• Premature birth
• Allergies to products not in vaccine
• Family history unrelated to immunosuppression
• Need for TB skin testing
• Need for multiple vaccines

28
Invalid ContraindicationsMinor Illness

• Low grade fever
• Upper respiratory infection
• Otitis media
• Mild diarrhea
• Only one small study has suggested decreased
  efficacy of measles vaccine in children with URI
• Findings not replicated by multiple prior and
  subsequent studies
• No evidence of increased adverse reactions

29
Screening Questions

• Allergies to food or medication?
• How is your child today?
• Any problem after last shots?

30
Screening Questions

• Problems with immune system
• Anyone in household with immune problems?
• Blood products in last year?
• Pregnant?

31
(No Transcript)
32
SPECIAL HOSTS

• IMMUNOCOMPROMISED
• Live vaccines are contraindicated
• Inactivated vaccines given per schedule

33
HOUSEHOLD CONTACTS

• Give MMR
• Vaccine virus is not transmitted
• Varicella also given
• Transmission of vaccine virus rare
• Disease if it develops is mild

34
Immunosuppression
Corticosteroids

• gt20 mg per day if wt gt10 kg
• gt2 mg/kg per day
• NOT aerosols, topical, alternate day, short
  courses

35
Recommendations for Routine Immunization of
HIV-infected Children
Vaccine Varicella MMR All others
Asymptomatic Yes Yes Yes
Symptomatic No No Yes
Yesvaccinate Nodo not vaccinate
Yesvaccinate Nodo not vaccinate
36

• PATIENTS TREATED WITH IG / BLOOD PRODUCTS
• Depends on dose
• MMR / Varicella give at suggested intervals

37

• PRETERM INFANTS
• Immunize per chronologic age
• Use regular vaccine dosage
• Exception Hepatitis B vaccine

38

• PREGNANCY OF RECEPIENT
• Live viral vaccines are contraindicated
• Theoretical risk to fetus
• No cases actually observed with congenital
  rubella or varicella
• Termination of pregnancy is not routinely
  indicated

39

• PREGNANCY OF MOTHER OR OTHER
• HOUSEHOLD CONTACT
• v MMR vaccine Vaccine virus not
• transmitted
• v Varicella vaccine Vaccine virus transmitted
• Frequency rare
• Mild / Asymptomatic infection

40

• RECEPIENT IS BREASTFEEDING
• No vaccine is contraindicated
• Only rubella vaccine virus isolated from human
  milk.

41
EGG ALLERGIES

• MMR vaccine can be given without prior skin
  testing
• Influenza contraindicated if immediate
  hypersensitivity reaction to eggs

42
(No Transcript)
43

• Alex is a 1 month 25 day old infant who received
  his Hepatitis B 1 at birth and is here for a
  well visit. Is he due for any shots and can he
  get them today ?

44

• 2 month visit
• DTaP1 Hib1 IPV 1 PCV71
• Does he have to return in 5 days for these?
• Can he get HBV 2 today ?

45

• Alex comes back for a sick visit at age 2 months
  20 days.( 25 days later) He has a stuffy nose and
  is coughing with an axillary temperature of 99 F.
• Can he get his DTaP 2, Hib 2, IPV 2 and HBV
  3 today ? Mom is keen on getting them as it will
  save her an extra trip.

46
4 month visit

• DTaP 2
• Hib 2
• IPV 2
• PCV7 2

47

• Alex comes back at age 4 months. His mother
  reported that his thigh was red and swollen after
  his previous shots.
• There is a strong family history of allergies
  including penicillin allergy. His older brother
  Josh had a bad reaction after DTaP.
• Joshs whole leg had swelled up and he had run a
  high fever too. Can Alex still get his shots ?

48
ADVERSE REACTIONS to DTaP

• Minor
• 2 to pertussis component
• Redness edema pain induration at inj site
• drowsiness fussiness crying
• Anorexia vomiting
• slight to moderate fever

49
MINOR REACTIONS

• Usually occurs within several hours
• of immunization
• Subsides spontaneously without
• sequelae
• Much less common with DTaP than
• DTP
• NOT CONTRAINDICATIONS

50
ALLERGIC REACTION

• Anaphylaxis 2 cases per 100,000
• IS A CONTRAINDICATION
• Transient urticarial reactions
• Not anaphylactic ( IgE ) unless seen within
  minutes
• Serum sickness reaction
• Unlikely to recur
• NOT A CONTRAINDICATION

51
Contraindications to DTaP

• 1. Immediate anaphylaxis to vaccine
• 2. Encephalopathy within 7 days
• Coma , decreased conciousness prolonged sx
• 3. Progressive neurologic disorder
• infantile spasms, progr. encephalopathy
• uncontrolled sx

52
PRECAUTIONS

• These conditions may increase chance of adverse
  events
• Do not cause permanent sequelae
• Weigh risk versus benefit
• Community outbreak, foreign travel

53
PRECAUTIONS for DTaP

• 1. Seizure fever within 3 days of DTaP
• Incid 1 in 1750 for DTP
• 2. HHE or hypotonic-hyporesponsive episode
  Collapse or shock like state within 48 hrs
• Incid 1 in 1750 for DTP
• 3. Fever gt 40.5 C ( 104.8 F ) within 48 hrs.
  Incid 0.3

54
PRECAUTIONS for DTaP

• 4. Persistent severe inconsolable screaming /
  crying for three or more hours within 48 hrs.

55
DTaP NOT CONTRAINDICATED

• F/H of Seizures
• F/H of SIDS
• F/H of adverse reactions to DTaP
• Stable neuro conditions
• CP, well controlled sx, develop delay
• Hx of PCN allergy ,relatives with allergy

56
IN PERSPECTIVE

• DISEASE
• Diphtheria
• Death 1 in 20
• Tetanus
• Death 3 in 100 Pertussis
• Pneumonia 1 in 8 Encephalitis 1 in 20 Death
  1 in 200

• VACCINE
• Continous crying with
• full recovery 1 in 100
• Convulsions or shock then full recovery
• 1 in 1750
• Acute encephalopathy
• 0-10.5 in 1,000,000
• Death none proven

57
(No Transcript)
58
(No Transcript)
59
(No Transcript)
60

• Alex comes back at 6 months for a well visit.
  What shots does he need ?

61

• 6 MONTHS
• Hep B 3 ( Min age 6 mo 4mo after 1st )
• DTaP 3
• Hib 3
• IPV 3
• PCV7 3

62

• Alex will be 1 year old tomorrow. Mom does not
  want to give him shots on his birthday so can he
  get them today?
• Also she has heard that MMR has egg in it and he
  breaks out with hives when he eats eggs. Can he
  get the MMR ?

63

• 1 YEAR OLD
• Hib 4 ( Min age 1 yr 2 mo after 3rd dose)
• MMR 1 ( Min age 1 yr )
• Varicella ( Min age 1 yr )
• PCV7 4 ( 2 mo after 3rd dose )

64
MMR Vaccine

• Live attenuated
• Measles Mumps Chick embryo cell culture
• Does not have significant egg white
• ( ovalbumin ) cross reacting protein
• Rubella Human diploid cell culture

65
ADVERSE EVENTS

• MINOR ( after 7-12 days )
• 1. Fever gt 39.4 C ( 103 F )
• Lasts 1-5 days
• O/w Asymp
• 5-15
• 2. Transient rash 5

66
ADVERSE EVENTS

• Moderate to severe
• 1. Febrile seizures
• Simple feb sx
• Not at increased risk of epilepsy
• 2. Transient thrombocytopenia
• 2-3 weeks after ( upto 2 months )
• 1 in 25,000 1 in 40,000
• Past/H of tcytopenia / vaccine tcytopenia
• 3. Encephalitis / Encephalopathy lt 1 in million

67
CONTRAINDICATIONS

• 1. Anaphylaxis to prior vaccine
• 2. Anaphylactic neomycin or gelatin allergy
• 3. Pregnancy
• 4. Immunocompromised states

68
(No Transcript)
69
(No Transcript)
70

• Alex returns for his 15 month check up.
• Mom says that he broke out with chicken pox 3
  weeks after his last set of shots.
• She was worried because her nephew who has
  leukemia was staying with them at the time.

71
VARICELLA

• MISCONCEPTIONS
• 1. Chicken pox is a mild disease
• FACT 10,000 Hospitalizations and 100 deaths /
  year
• 2/3 rds the admissions and half the deaths occur
  in children
• Most imp risk factor for invasive GAStrep

72

• 2. Vaccine is not very effective
• FACT 85-90 effective during outbreaks
• 100 effective agnst severe disease
• Mild varicella like illness in 1-4 of immunized
  kids with rapid recovery
• Rash so mild that it may resemble insect bites
• Child is potentially infectious

73

• 3. Immunity does not last lifelong
• FACT Protection for at least 11 years in US and
  20 years in Japan
• Other live viral vaccines Immunity lasts a
  lifetime

74

• 4. Is it a safe vaccine ?
• YES Reactions are mild
• Minor inj site 20
• Local rash 3-5
• Gen varicelliform rash after 5-26 days in
• 3-5
• Zoster like illness 2.6 / 100,000 vaccine
• doses distributed

75
(No Transcript)
76

• 15 MONTHS 18 MO
• DTaP 4

77

• 4-6 YEARS ( PRE KINDERGARTEN )
• DTaP 5
• IPV 4
• MMR 2

78

• 11 yrs
• Td
• Booster every 10 yrs

79
TAKE HOME MESSAGES

• Vaccines are safe
• Vaccines are very effective
• Educate yourself so that you do not propagate
  misconceptions
• Ask yourself Is the child more likely to die of
  the vaccine or the disease? before you with hold
  any vaccines
• Threat from vaccine preventable diseases is real

80

• Vaccination is one of the greatest achievements
  of medicine
• It has spared millions of people the effects of
  devastating disease