1. Infectious Disease & Immunity

2. 3) Vaccine Preventable Diseases
Part 1
1) Immune System
2) Vaccinations
3) Vaccine Preventable Diseases

3. 1; Immune System

4. Immune system Neonates have immature immune system
(esp. adaptive system; lymphocytes, antibodies)
Lymphocytes ↑ (thymus) & mature with antibody production relative to exposure
Foetal/ Neonatal monocytes, slow to process foreign antigens
Infants produce a/b against simple proteins
(eg. Vaccines) not polysaccharides until 2 years

5. Foetal Lymphocytes from 9/40 in liver
Bone, liver, spleen 12/40
T-cells from 14/40 &
In utero sterile environment (ideally)
Therefore no anti-bodies produced
Mum’s IgG only crosses placenta

6. Neonatal antibodies IgG; Transplacental ie maternal
60% of adult’s level at 1 year
100% by 6-10 years
IgM; v low at birth; 75% adult level at 1 yr *
IgA, IgD, IgE; 10-40% at 1 yr

7. Exposure; 7-8 viral infections/yr
↑ with contacts (creche / school)
Vast array of childhood infections from benign to critical; your job to find out which

8. Immune system; ‘in balance’
Infection; viral/bacterial/opportunistic
Hypersensitivity; Allergy, Atopy, Intolerance
Autoimmune disorders
Immunodeficencies
Therapeutic; Vaccinations

9. “Medicine’s greatest lifesaver”
2; Vaccinations
“Medicine’s greatest lifesaver”

10. } } 12 vaccines Mycobacterium BCG* x 1 Meningococcal C Men C x 3
Diphtheria
Tetanus
Pertussis 6in1 x 3
Polio
Haemophilus influenza b
Hepatitis B
Meningococcal C Men C x 3
Pneumococcus PCV x 3
Measles
Mumps MMR* x 2
Rubella } }

11. Age
Vaccination
Birth
BCG
2 months
6in1 & PCV
4 months
6in1 & Men C
6 months
6in1 & Men C & PCV
12 months
MMR & PCV
13 months
Men C & Hib
4 – 5 years
4in1 & MMR
11-14 years Td

12. Those born before July 2008
Age
Vaccine
Birth
BCG
2 months
5in1, MenC
4 months
6 months
12-15 months
MMR, Hib
4-5 years
4in1, MMR
No Routine Hepatitis B or Pneumococcal vaccine
PCV Catch-up programme (for <2 year olds)

13. Table : Vaccination Schedule for Infants and Children 2012
Age Type of vaccine
0-1 Week OPV0 dose , HepB1 , BCG
2 Months OPV1 , PENTA1,ROTA1
4 Months OPV2 , TETRA1,ROTA2
6 Months OPV3 , PENTA2,ROTA3
9 Months Measles + VIT A
15 Months MMR (Measles , Mumps , Rubella)
18 Months TETRA2, OPV First Booster dose +
VIT A
4-6 Years DPT , OPV Second Booster dose +
MMR2

14. Table : National Immunization Schedule for Infants and Children 2015
Age Type of vaccine
0-1 Week HepB1 , BCG + OPV0dose
2 Months HEXA 1,ROTA1 ,PREV13-
1+OPV1
4 Months HEXA2,ROTA2,PREV13-2 +
OPV2 6
Months HEXA3,ROTA3,PREV13-3 +
OPV3
9 Months Measles + VIT A
15 Months MMR(Measles , Mumps , Rubella)
18 Months PENTA (DTP+IPV+Hib ) OPV +
VIT A
4-6 Years TETRA (DTaP +IVP ) + OPV + MMR

15. Why Immunise?
In 1974, only 5% of the worlds children had access to vaccines.
A global effort in the early ’80’s aimed to provide six vaccines to 80% of children worldwide
Immunisation now saves >3,000,000 lives each year
Protects millions more from illness and permanent disability

16. Other vaccines
Influenza
Varicella
Hepatitis A
HPV
Travel vaccines

17. What is immunisation?
Immunisation is the process of inducing or providing immunity artifically.
This may be done by the administration of a vaccine, toxoid or externally produced antigen in order to stimulate antibody production.
The aim; to reduce the incidence of, or to eliminate a particular disease.
Immunisation has both a direct and an indirect effect.
Direct effect; antibody protection in the individual
Indirect effect; reduction of the incidence of the disease in others – so called ‘herd immunity’

18. Vaccine Considerations
Pathogen factors; How common?
How dangerous / complications?
Vaccine factors; vaccine immunogenicity
efficacy, side-effects & risks?
Host factors; maturity immune system,
When is infant most at risk of this disease?
Population factors; disease prevalence,
vaccine uptake & herd immunity,
cost-benefit

19. Live Attenuated
Killed Orgs
Subunits
Measles
Polio (IPV)
Hib
Mumps
Men C
Rubella
Pneumo (PCV)
BCG
Influenza
Hep B
Acellular Pertussis
Varicella
Cellular Pertussis
Cholera/typhoid/ yellow fever
Cholera/Typhoid/Rabies
Hep A
Oral Polio

21. MMR Vaccine: Is It Really A Factor In Autism?
There has been a concern about a link between the MMR (measles, mumps, rubella) vaccine and the development of autism in children because:
MMR vaccine is first given at age 12 to 15 months.
The first signs of autism (e.g. poor social interaction and speech, repetitive behaviors) often appear between 12 to 18 months of age.
12 months
15 months
MMR vaccine first given
0 months
Birth
First signs of autism

22. Independent Studies Have Found No Link Between Autism and MMR.
A United States study by Dr. Loring Dales showed that the number of autism cases in young children increased even when the number of MMR vaccines decreased over the same time period!
A British study by Dr. Brent Taylor showed that the number of diagnosed autism cases did not increase after the MMR vaccine was introduced in 1988.
If a link existed between the MMR vaccine and autism, then one would expect the number of autism cases to increase or decrease over time as the number of children immunised with MMR decreases or increases over the same time. No study has shown this trend.
Additional studies conducted in the United States and in Europe have found no association between the MMR vaccination and autism.

23. WHO opinion on MMR
"WHO has noted that other scientists have not been able to reproduce the results claimed by Dr Wakefield and his team regarding measles virus in the gut. His published observations regarding the onset of autism following administration of MMR vaccine do not meet the scientific criteria required to suggest that the vaccine is the cause. Other studies not cited by Dr Wakefield find no link with autism or Crohn's disease."
WHO strongly endorses the use of MMR (measles, mumps and rubella) vaccine on the grounds of its convincing record of safety and efficacy.

24. Late Entrants To some European countries Health Care System
MMR; Immunisation recommended
2 doses recommended between mo and 4-6 yrs at least 1 month apart
Men C; recommended under 22 years
Hib; Recommended under aged 4 years
( 3 doses < 1 yr, 1 dose > 1yrs)
Polio; 4 doses recommended before the age of 4-6 yrs
DtaP; recommended under 12 years
If it is likely 3 or more doses given,
serological testing for IgG antibodies +/- booster
If a child at presentation is > 10yrs Td is given

25. Contraindications/ Precautions

26. ……..NOT Contraindications
Family history of adverse reactions to immunisations
Minor infections without fever or systemic upset
Family hx of convulsions
History of measles, mumps, pertussis in the absence of proof of immunity
Child’s mother is pregnant or Child being breast-fed
Impending surgery
Child over the recommended age
Corticosteroid replacement therapy

27. Diphtheria Corynebacterium diphtheriae Affects upper respiratory tract
Incubation – 2-5 days
Spread; droplet/close contact
Disease characterised by an inflammatory exudate  obstructive membrane over the airway
Other manifestation:
Myocarditis
Vocal cord paralysis
Guillain Barre type ascending paralysis
Since vaccination; virtually eliminated in Ireland
Vaccine
Toxoid
Component of 6 in 1
Booster at 4-5yrs and low dose booster at yrs
Adverse reactions
Transient local reactionc occur in > 50%
Malaise, headache and transient fever occur occasionally
A special low dose diphtheria toxoid must be used in those 1o yrs and over who are having primary immunisation.( three doses at intervals of 1 month)

28. Tetanus Vaccine Clostridium tetani
Toxoid
Poor immunogen
Primary immunisation
6 in 1, three doses
Booster dose at school entry and at 11-14yrs
Immunised adults who have received 5 doses do not need further booster doses
Clostridium tetani
Muscular rigidity with superimposed contractions
Organism is ubiquitous
Nb; puncture wounds, bites etc.
Incubation period: 4-21 days

30. Pertussis (Whooping cough)
Bordetella pertussis
Highly infectious (90% of nonimmune contacts acquire it)
3 phases
Transmitted; droplets etc.
1-2 week incubation
Endemic with periodic outbreaks
Diagnosis; often clinical
Peri-nasal swab; poor yield
Lymhocytosis
Treatment;
Isolate
Erythromycin reduces infectivity
Supportive
Vaccination

31. ‘100 day cough’ Catarrhal phase; 1-2 weeks of low fever, URTI
Highly infectious
Transmission; Droplet/ close contact
Paroxysmal phase; Whoop (gasps for breath between coughing fits) 3-5 weeks
Often associated vomiting etc.
Recovery phase; 2-3 weeks
Complications;
Apnoea in neonates
Bronchopneumonia
Cerebral hypoxia; Seizures, Encephalopathy
Death

32. Efficacy variable; 35 – 100% in studies
Vaccine
Acellular pertussis
6 in 1 x 3
Booster at 4-5 yrs
No upper age limit but considered unnecessary > 7 yrs
Efficacy variable; 35 – 100% in studies
Previous concern re; seizures induced by Cellular Vaccine (not used anymore)

33. Pertussis - special precautions
Advice from the child’s paediatrician may need to be sought prior to immunisation where there is:
A personal history of convulsions
An evolving neurological problem
If an event listed in precaution section has occurred after a previous dose

34. Poliomyelitis Caused by polio virus 1-3 Transmission;
faecal/oral, droplet
Incubation: days
Clinical disease
Non-paralytic fever
Aseptic meningitis
Paralysis
Most infections asymptomatic
Pre-vaccine;
20,000 cases/yr USA
1,900 deaths /yr
Ireland most recent case 1984
Endemic in developing world
Vaccine
IPV since 2001
Part of 6 in 1
3 doses + 4th at 4- 5 yrs
OPV not recommended

35. Haemophilus influenzae type B
Hib vaccine introduced 1992
80% of invasive haemophilus infections caused by type B
After 12 months of age, Hib disease declines
Clinical disease includes:
Meningitis
Epiglottis
Septicaemia
Cellulitis
Osteomyelitis
Septic arthritis
Vaccine
Capsular poly or oligosaccharide
Part of 6 in 1
3 doses + booster
If first dose given at > 1 yr need only 1 dose
Children > 4 yrs do not need immunisation with Hib
Persons with asplenia or undergoing splenectomy should be vaccinated
Adverse reactions:
Mild local reactions in 20%
Systemic reactions uncommon

36. Hib Treatment Index case; tx with cefotaxime or ceftriaxone
Immunise 1 month after disease if < 2 yrs
Household contacts / Play-group/ creche; chemoprophylaxis
Except pregnant women
Non-immunised contacts < 4yrs need vaccine
All household contacts irrespective of age or immunisation history IF there are any unvaccinated children< 4yrs
Chemoprophylaxis; Rifampicin
Neonates and infants < 1 yr : 10mg/kg od for 4 days
Children > 1 yr: mg/kg od for 4 days ( max 600mg/day)
Adults : 600mg one daily x 4 days

37. Hepatitis B DNA virus Highly contagious
30% transmission rate with puncture injury
High risk contacts
10% chronic infection, 1% fulminant hepatitis
Risk of Hepatocellular Ca

38. Hepatitis B vaccination
Traditionally only vaccinated high risk groups
Sex workers
Individuals who change sexual partner frequently
IVDU’s
Prisoners
Tattoo artists
Homeless people
Immigrants from, or travellers to, areas with a high prevalence of HBV
Security and emergency services personnel
Family contacts of HBV pts
CRF / HIV / chronic hepatitis
Healthcare workers

40. Hepatitis B vaccine Vaccine; HBsAg in 6in1
Primary Immunisation Schedule (since July)
At 2, 4, 6/12
At birth with HBIG if risk of vertical transmission
+ follow-up testing
No Catch-up unless at risk

41. Meningococcus C Neisseria Meningitidis Gram neg. cocci
Causes Meningitis, Septicaemia
Notifiable disease
Contact tracing & chemoprophylaxis required

44. Contact tracing/ prophylaxis
Antibiotic prophylaxis for close contacts of confirmed or suspected cases:
Close contacts defined as those who in the seven days prior to the onset of illness in the index case
Have shared living or sleeping accomodation
Had mouth kissing contact with the patient
Nursery/creche /daycare contacts
Medical personnel who have had ‘intimate’ contact with the patient ( mouth-to-mouth, intubation)
Rifampicin is drug of choice
Alternative prophylaxis is Ceftriaxone 250 mg im for adults and 125mg for children
For vaccine preventable strains (A, C, W-135) vaccination is offered.

45. Streptococcal Pneumoniae
Capsular organism
Gram + Diplococci
Some asymptomatic carriers
Diseases;
Meningitis with effusions
Pneumonia with effusions
Bacteraemia/Sepsis
Otitis Media
Sinusitis

46. Pneumococcal Conjugate Vaccine
7 serotypes (75-80% invasive pneumococcus)
↑ immunogenicity with mutant diphtheria toxin
> 90% effective
23-valent polysaccharide available
for high risk children > 2years age
eg. Asplenia
Effective for 5 years
Not in Primary Immunisation Schedule

47. Measles Transmission; airborne/droplet Incubation; 10-14 days
Clinical;
Prodrome; high fever, harsh cough, coryza, conjunctivitis,
Rash; ‘morbilliform’, maculo-papular
Begins d3-6 from hairline, down face to trunk
Lasts up to 10/7
Koplik’s spots

48. Measles (Rubeola) Complications; RNA Paramyxovirus
Clinical diagnosis
Salivary swab measles IgM
Treatment
Supportive
Ribavirin if patient Immunocompromised
?Contacts
Prevention: HNIG within 6/7 if imunocompromised contact
Complications;
Otitis, pneumonia, croup
Encephalitis 1/5000 within a week of rash
15% Mortality
20-40% Neuro sequelae
Late complication;
SSPE (subacute sclerosing panencephalitis) 1/100,000 48

49. Measles Vaccine; MMR 12-15 months of age, 2nd dose at 4-5 yrs
Can be given to those with history of measles, mumps or rubella infection
Mini-measles can occur days after immunisation
Mild pyrexia and erythematous rash
Measles outbreak
Immunise all susceptible individuals within 72 hrs
Contraindications;
Pregnancy is a contraindication and should be avoided for 2 months after vaccination
Untreated malignancy and immunodeficiency states (except HIV)
Immunosuppressive therapy
History of anaphylaxis to a previous dose

50. Mumps Acute viral illness
Swelling of one or more salivary glands usually the parotids
CNS involvement is frequent
Symptomatic meningitis occurs in <10%
Rarely transverse myelitis, cerebellar ataxia or encephalitis can occur
Orchitis occurs in 20% of post-pubertal males
Sterility rare
Other manifestations
Arthritis, carditis, nephritis, pancreatitis, thyroiditis, hearing impairment
Transmission is by droplet
Incubation period: days
Vaccine; live MMR

51. Rubella Rubella – difficult to diagnose
Fever <38.5, LN + (esp Post Triangle)
May have splenomegaly, palatal petechiae
Mild self limited disease in children – % subclinical
Incubation 2 – 3 weeks
Infectious (droplets) for <1wk from rash onset
Buccal swab, urine, rising antibody titre
Rare complications:
Polyarthralgia / Polyarthritis
Thrombocytopenia
Encephalitis (1 in 6000) 51

52. Congenital Rubella LBW, growth retardation
Microcephaly, learning disability, psyche
Microphthalmia, catarract, glaucoma
Micrognathia
Sensori-neural deafness
Hepato-Spleno-megaly (transient), diabetes
Thrombocytopenic purpura ‘blueberry muffin’
PDA

53. Congenital Rubella 1964-1965 USA; Rubella epidemic; 12.5mil cases
with 20,000 cases congenital rubella
2001; 19 cases Rubella in USA
Serology checked on antenatal booking bloods
>80% women infected in 1st trimester; affected infants
Infants with congenital rubella may shed virus for over a year 53

54. MMR Prevention: Active vaccination
Rubella component of MMR vaccine occasionally produces mild arthralgia especially in post pubertal girls (25%)
Pregnancy remains a contraindication
(no evidence of congenital rubella related to vaccine)

55. HIV And Immunisation
Children With HIV infection whether symptomatic or asymptomatic should receive:
DtaP, IPV, Hib, Men C as per primary schedule
Yearly influenza vaccine beginning at 6 months
Pneumococcal (conjugate) vaccine at 2,4 and 6 months
MMR at 14 months ( unless severely immunocompromised), 2nd dose 1-2 months later
BCG if infant has 2 negative HIV PCR tests in the first 6 weeks of life
Hepatitis A
Hepatitis B

56. Summary Neonates & Infants immature immune systems
Vaccines very effective protection
Know schedule (old & new & catch-up)
Know diseases they prevent (MCQs)

57. Age
Vaccination
Birth
BCG
2 months
6in1 & PCV
4 months
6in1 & Men C
6 months
6in1 & Men C & PCV
12 months
MMR & PCV
13 months
Men C & Hib
4 – 5 years
4in1 & MMR
11-14 years Td

58. Sensitivity of vaccines to freezing
Vaccines damaged by freezing
DPT DT Td TT Hepatitis B
Vaccines unaffected by freezing
BCG * OPV Measles * Mumps

59. IMPORTANT!
• Measles, BCG and mumps vaccines must be reconstituted only with the diluent provided by the manufacturer of the vaccine in use.
• Never use other diluent.
• Diluent must be cold, between 0 and 8 degrees Celsius, before being mixed with the vaccine.
• When reconstituted, the vaccine must be used within 6 hours, and any remainder discarded

60. IMPORTANT:
• All vaccines lose potency gradually, even at correct.
• Storage temperatures - observe expiry dates.
• All vaccines suffer much faster loss of potency when exposed to temperatures above +8 degrees C.
• Any loss of vaccine potency is irreversible.
• Damage due to successive exposures to heat or light is cumulative.
• Hepatitis B, DPT, DT, Td and TT are destroyed by freezing.
• BCG and measles vaccines are damaged by exposure to strong light as well as heat.

61. SUMMARY POINTS!
• In health facilities, keep vaccines for a maximum of one month. • Store all vaccines in the refrigerator at 0 to +8 o C.
• Place OPV, measles and mumps vaccine closest to the evaporator.
• Place DPT, DT, Td, BCG and hepatitis B on lower shelves, away from the evaporator;
• Do not keep vaccines in the door shelves.
• Keep sealed water bottles in the bottom of the refrigerator.
• Keep diluent next to its vaccine or mark it clearly if it is placed on a different shelf

62. Thank you