Dr Emma Best - GP CME Sat 0830 Best - Paediatric Vaccination Update.pdf · Measles, rubella and...
Transcript of Dr Emma Best - GP CME Sat 0830 Best - Paediatric Vaccination Update.pdf · Measles, rubella and...
Dr Emma Best Paediatric Infectious Diseases Consultant
Starship Children’s Hospital
Vaccine preventable diseases
Acknowledgements for slides Dr. Cameron Grant, Associate Professor, Paediatrics, University of Auckland Paediatrician, Starship Children’s Hospital, Auckland Dr Nikki Turner, Director, Immunisation Advisory Centre, University of Auckland Dr Anusha Ganeshalingham PICU fellow intensive care for pertussis info Google Images
Dr Emma Best
Senior Lecturer, Department of Paediatrics, University
of Auckland
Paediatric Infectious Diseases Specialist
Starship Children’s Hospital
Immunisations again…
Declarations
Today am invited speaker by GSK who have paid my travel and accommodation
Do not accept honoraria
Participant in research groups with consumables funded by Wyeth (Pfizer) and GSK
Member of the Anti-infectives committee of Pharmac
Outline
Describe vaccine preventable diseases which I still see
Using presentations and complications
To help understand importance of vaccinating still and the public health significance
Discuss aspects of prevention of the disease and vaccine uptake
Immunology made simple
Vaccines stimulate body’s defence mechanisms (immune system) against an infection
Help immune system detect and destroy infection when encountered in the future without development of significant symptoms or complications of that disease
www.science.org.au/immunisation.html
Some vaccines can provide herd immunity
Indirect protection from infection caused by immune individuals
Exposure to antigens?
Will use Photos to introduce some vaccine preventable diseases and some of their complications
Name the vaccine preventable disease
Explain what caused the bleeding
Coughed so hard that she has burst the blood vessels on the surface of her eyes
“100 day
cough”
Whooping cough
Pertussis
Illness with paroxysms of coughing, plus whoop, apnoea and vomiting.
Presentation of pertussis varies with age .. and immunisation status
Infant
Apnoea and/or cyanosis and/or paroxysmal cough
Children
Non-immunised cough increasing in severity over several weeks rapidly repeated, forceful coughs followed by desperate gasps
Well between paroxysms
Immunised – milder disease – still cough, less forceful
Presentation of pertussis varies with age
Adult
Persistent cough,worse at night and often paroxysmal
Awoken by a ‘choking sensation’
scratchy throat, sweating attacks
Post-tussive vomiting and whoop
Every 3-5 years escalating epidemics at the end of 2011 – it was that time again, and proving to be a record
breaker
Number of pertussis notifications by week
reported, 2010 - 2013
ESR, Pertussis Report: April 2013.
NZ epidemic statistics are being mirrored around the world – in the
UK
USA..
Australia
34 Admissions to SSH PICU…and
counting
3 deaths
And cohorting up to 4 apnoeic babies per bay (4 times this epidemic)
Critical Pertussis
Malignant or fulminant
Infants
6/10 will be hospitalized in <6 mth age group
Reservoir is adults/adolescents
Factors associated with fulminant
pertussis – unimmunised or partly,
age< 6 months
To control pertussis you have to do immunisation well
Increase coverage from < 80% to 80- 90% and you decrease disease burden 10 fold,
Increase coverage to 95% or greater and you get another 10 fold reduction
Pertussis hospital discharge rate in NZ per 100,000 person years
J Paed Child Health 2007 Somerville, Grant et al
Vaccination has changed pertussis epidemiology
Booster vaccination: Prolonged protection 6-10 years
No additional booster: immunity wanes Susceptible adults:
reservoir of pertussis
Unvaccinated or partly vaccinated infants: susceptible
Primary vaccination: 4-6
Why are pertussis outbreaks occurring worldwide?
Vaccination does not change the periodicity of epidemics
Immunity wanes – perhaps faster than imagined
The current vaccine is not perfect and needs very good coverage
Why is pertussis in NZ so bad?
Very infectious and imperfect vaccine
+ NZ has not achieved good coverage
+ NZ has not achieved timeliness
+ NZ has changed our schedule several times (including dropping a dose in 1970’s)
+ NZ has poverty and crowded housing issues
Protect the young immunise …
Pregnant women, post partum
Older siblings/school aged children
Close contacts – fathers, grandparents
Early childcare workers
Healthcare workers (!)
Give vaccines on time and boosters
Name the Vaccine preventable disease affecting this newborn baby?
What is this complication from the same vaccine preventable disease?
Congenital cataracts – opaque lenses
Rubella
Was a common childhood illness -mild symptoms
Transmission by respiratory secretions
Rash is similar to many other infections
enlarged lymph nodes (back of neck, behind ears)
Cataracts Nerve deafness Heart defects
Microcephaly (small brain) Mental retardation Behavioural problems
Inflammation • Liver • Lungs • Bone marrow
But for newborns whose mothers acquire rubella in the first trimester …..
Blueberry muffin baby - due to bone marrow failure
Rubella in New Zealand
New Zealand Immunisation Handbook 2011
Rubella in New Zealand
Not common
Between 2005 and 2010, 49 cases of rubella were notified.
43 cases in children < 9 year
Worldwide, less developed countries offer only monovalent measles vaccine (India, Indonesia, Timor) so no control/monitoring of rubella
Measles Conjunctivitis, rash (cough) look miserable/sick!
Measles Transmission by respiratory secretions
Highly infectious
Rash is similar to many other infections
Measles
Days 2-4: Fever, red eyes, runny nose, Koplik spots
Day 3-7: Maculopapular rash (confluent)
Child most unwell day 1-2 of rash
Complications in 10%
Diarrhoea and dehydration
Otitis media, pneumonia, croup
Encephalitis 1:1,000 cases
Deaths in early 90’s and one in 1997 outbreaks
1969-1970 introduced
1990 MMR
Two dose schedule 1992,
changed to 15 mths in 1996
Measles in New Zealand
Epidemics still occur but immunisation has increased the time between them and many less cases
To prevent epidemic 95% of the population must be immune
Vaccine efficacy of 90-95%
Hence 2 dose schedule needed
WHO global eradication goal
Name vaccine preventable disease and country where these resurgent cases still seen
Poliomyelitis NZ 1915-2000
Western pacific polio free since 2000
Imported Case of Poliomyelitis, Melbourne, Australia, 2007- 22-yr-old
Pakistani student who had travelled home to Nthern Pakistan on holiday
Measles, rubella and polio are examples of herd immunity
and how we are part of both a mobile and global community
Polio will be eradicated but is not yet!
South East Asia is aiming for measles eradication ..but it is years away
Millions receive monovalent measles vaccine (M not MMR) so areas with little rubella control
Tetanus
u Clinical term for muscular rigidity caused by the toxin produced by Clostridium tetani
u Spores found everywhere in environment particularly manure/soil, not “infectious” or passed between people
u Easily introduced to a wound at time of injury especially deep penetrating dirty wounds
New Zealand, tetanus
New Zealand Immunisation Handbook 2011
New Zealand tetanus
Last 15 years, 30 cases of tetanus (2 cases per year in NZ) notified*
Mostly older adults - vaccinated ‘years ago’, no booster
Children – all unimmunised (4)
Starship experience with tetanus
Difficult to achieve full immunisation in families with fixed anti-immunisation beliefs
Publicity around cases increases discussion and may help some reconsider stance
Tetanus - a good reminder that for some diseases there is no herd immunity
Haemophilus influenzae type b (Hib) causes meningitis, periorbital cellulitis or epiglottitis
Epiglottitis
Fever, breathing difficulties, to
painful swallowing, drooling and then
complete airway obstruction
Haemophilus influenzae type b…………
used to be the paediatrician’s bread and butter
0
10
20
30
40
50
60
1st 4th 3rd 2nd 1st 4th 3rd 2nd 1st 4th 3rd 2nd 1st 4th 3rd 2nd 1st 4th 3rd 2nd 1st 4th 3rd 2nd 1st 4th 3rd
1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 20092010
Ca
se
s
Hib laboratory confirmations 1990 - 1995 and notified cases 1996 - 2010
Source: Immunisation Advisory Centre, University of Auckland
Pre immunisation was the commonest cause of bacterial meningitis in children
1 in 350 NZ children aged < 5 years had an episode of invasive Hib infection
Hib epidemiology
Transmission by direct contact and respiratory secretions
Immunisation reduces carriage of bacteria in nose
Preschool children are ones affected so immunisation works very well - provide immunity for crucial age
If 80% of population vaccinated disease virtually disappears
Leung B , Best EJ et al ‘Haemophilus influenzae type b disease in Auckland children during the Hib vaccination era, 1995–2009.’ NZ Med Journal, Nov 2012
1-2 cases per year, disease still same spectrum, most unimmunised
Neisseria meningitidis Meningococcaemia Meningococcal meningitis (brain inflammation)
Meningococcal epidemiology
Asymptomatic colonisation
5 to 15% of population
Carriage increased by smoking (also
passive), crowding, viral infections
Respiratory droplet and secretion spread,
then infection in those at increased risk
Not as simple
as Hi type b
5 serogroups
that cause
disease
A, B, C, W135
and Y
Meningococcal bacteriology
Which New Zealanders?
Those in crowded houses Doubling of risk with the addition of 2 adolescents or adults to
a 6-room house (Baker PIDJ 2000;19 )
Age < 5 years, especially age 6 to 12 months
Maori and Pacific children (2 to 3x increased risk)
Household contacts 600x risk in week after index case
Students in hostels (adolescence the other risk group)
…anyone ..
Meningococcal disease
Meningococcal Vaccines available No longer MenzB
Conjugate meningococcal C
Polysaccharide quadrivalent A,C,W135 Y
Menactra conjugate A,C,W135,Y
Age range
Any but not long
lasting protection
particularly in infants
All ages and long
lasting
Over 2 years and
lasts about 5 years
Over 9months and
long lasting
Otitis media Pneumonia (and empyema) Meningitis pus and inflammation in the membrane
around the brain
Streptococcus pneumoniae
Pneumococcal disease
Pneumococcal epidemiology
Also not simple
90 (!) serotypes
Some more
invasive than
others
Pneumococcal bacteriology
Asymptomatic
colonisation in 30-
60% of young
children
Changed by season,
viral illness, antibiotic
prescribing,
socioeconomic
status
Invasive disease for
some
<2 yrs, >65yrs,
medical conditions
Non invasive disease
Ear infections,
pneumonia
S. pneumoniae substantial burden of disease Estimated annual hospital admissions per
100,000 in NZ children aged <5 years1*
23
295
808
*Before implementation of PCV7 immunisation in NZ
1. Milne, Vander Hoorn. Appl Health Econ Health Policy 2010;8:281–300
Paediatric pneumococcal disease in New
Zealand
Life threatening
Each year ≈ 150 cases of pneumococcal meningitis
and bacteraemia in children under 5 years old
10-11 deaths
13-26 cases of severe long-term disability
Pneumonia
3000 admissions per year
20 to 40% due to pneumococcal infection
Otitis media
A large proportion of antibiotic prescriptions
Pneumococcal vaccines
23 valent polysaccharide vaccine
Not immunogenic in children < 2 years old
Conjugate vaccines
Antigens from most invasive pneumococcal serotypes
Joined (conjugated) to a carrier protein
More complex molecule - creates an immune response in infants
Seroptypes causing IPD in Children <2 years and Adults ≥65 years
Laboratory Surveillance NZ 1998-2005
0
5
10
15
20
25
30
14 6B 19F 4 23F 9V 18C 19A 6A* 7F 8 3 22F 12F 1
Included in PCV-7 Not in PCV-7
Pneumococcal Serotypes
Pe
rce
nta
ge o
f S
ero
typ
es I
sola
ted
<2 years
≥65 years
Serotypes Causing IPD in Children <2 years and Adults ≥65 years - Laboratory Surveillance NZ 1998-2005
Jackson C Serious Pneumococcal Disease in NZ 2007 IMAC , University of Auckland
PCV vaccines Serotypes
Prevenar13™
4, 6B, 9V, 14, 18C, 19F, 23F
1, 5, 7F 3, 6A, 19A
CRM197 Diphtheria carrier protein
Serotypes
Serotypes
4, 6B, 9V, 14, 18C, 19F, 23F
CRM197 Diphtheria carrier protein
Prevenar™
PCV7 licensed in
2000
Introduced NZ June
2008
NTHi protein D
4, 6B, 9V, 14, 18C, 19F, 23F
1, 5, 7F
NTHi protein D T D
Synflorix™ Switched
to PCV 10
June 2011
3 + 1 schedule
6wks, 3mths, 5mths and 15 mths
New Zealand IPD rates
90% reduction in VT IPD
70% reduction in overall IPD Heffernan et al INVASIVE PNEUMOCOCCAL DISEASE IN
NEW ZEALAND, 2010
Young girl with a rash
Varicella – common childhood illness
COMMON YES – 90% have had chicken pox by age 14 yrs
So common that complications also common!
What is this common associated skin complication?
Cellulitis
What is this rare complication of this VPD?
Necrotising fasciitis – “flesh eating bug”
Typically Streptococcus pyogenes
Not so benign - severity of chicken pox
Mild disease 50 lesions (most breakthrough disease in vaccinated children is <50 lesions)
Moderate 200-400 lesions (most wild type)
Severe >1000 lesions
Although more severe in immunocompromise most deaths and hospitalisations occur in healthy people/children
SSH PICU again; varicella admissions
10 years review – 2-3 children per year
4 deaths
Currently looking at all hospitalisations due to varicella across New Zealand over 2 years in <15 yr olds
For every hospitalisation 90-150 GP visits
Varicella vaccine
• Varicella vaccine available since 1996 (live attenuated vaccine)
• Recommended but not funded, (about 17% uptake)
• Vaccines available in New Zealand:
• Varilirix Varivax
• Quadrivalent MMRV vaccine (Priorix-Tetra or ProQuad)
• Zostavax (herpes zoster vaccine for adults ≥ 50 years of age)
• Recommended for children from age 12m to 12yrs 1 dose effective for 80%, very effective at reducing serious infection
• Administered at 15m (with MMR, Hib & PCV10)
• Second dose (debatable) at 4yrs with MMR (effectiveness 2 doses >95%)
USA AUSTRALIA USA since 1995 Australia –
recommended 2003,
funded since 2005
Varicella vaccine
Common questions raised when talking about vaccinating chicken pox
Why – common childhood disease and better immunity from wild infection?
Vaccine immunity only lasts 20 years?
More shingles
2 doses?
Use MMRV or MMR + V ?
Common questions raised when talking about vaccinating chicken pox
Why? common and nasty
Vaccine immunity only lasts 20 years – no reason to believe this – live viral vaccine and antibody should present lifelong but without wild virus may need other boosting
More shingles? Less shingles after vaccine – theoretical concern of increased shingles in those whilst we “eradicate varicella with vaccine” – development of zostavax Reid S NZMJ 2012 125; 1354
• Give the varicella vaccine or the MMRV??
• So 1 jab (MMRV) or 2 jabs (MMR + V) at 15 months?
• NZ MOH recommends MMR+V at 15 months due to risk of febrile seizures
• What is the risk for febrile seizures?
• 1 additional febrile seizure is expected per 2500children vaccinated with MMRV when compared with MMR + V (if receive it aged 1-2 yr)
• No increased risk seen in those aged 4-6yrs who received MMRV
• Weigh up with other costs – pain of extra injection, risk of falling behind schedule, missing opportunity of vaccinating
Varicella vaccine or MMRV
A very current vaccine preventable disease -
Global community, herd immunity and not
Bacterial vaccines - the old’ish and new’ish
HIB, MENINGOCOCCAL AND PNEUMOCOCCAL
What’s in store?
PERTUSSIS
Polio, rubella Measles Tetanus
Varicella
Key messages
VPD -a reality in NZ and cause morbidity and death
Improved coverage and timeliness will change this
We are part of a global community of people (measles) and microbes (tetanus)
Effective bacterial vaccines give new invasive disease priorities - surveillance is important
Pertussis control is complicated
New vaccines such as varicella likely to impact positively both at population and individual level