Vaccine Scares

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Vaccine Scares

• Pertussis vaccine and brain damage
• HepB vaccine and MS
• MMR and autism and IBD
• Polio vaccine and origin of HIV
• Influenza vaccine and Guillain-Barré syndrome
• Lyme vaccine and autoimmune arthritis
• Thiomersal and neurotoxicity
• Aluminium hydroxide and macrophagic myofaciitis

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Pertussis Complications
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Hep B and MS

• Anecdotal evidence only
• Epidemiology shows no association (Confavreux
  et al, 2000)
• French government altered its Hep B vaccination
  recommendations

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Hepatitis b vaccination and MS in USA Ascherio
study(N E J Med 2001)

• Case control studies NIH
• 2 cohorts of 121700 and 116871 nurses
• MS validation, Vaccinations certified
• In vaccine recipients 192 MS 4,7
• In controls 534MS5,6
• OR(RR) 0,7 CI 95 0,3-1,8 not significant

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MMR ,IBD and Autism

• Reports of autism DPT go back to 1985 but no
  association could be established (IOM,1991)
• Report of autism and atypical colitis MMR
  reported by Wakefield colleagues in 1998 in 12
  children
• Epidemiological studies have failed to show an
  association

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Measles Virus

• Virus shows little antigenic variation
• Infects everybody once only
• Lifelong immunity ( persistent infection
  probably in macrophages)
• Very specific to man and therefore eradicable
• Infects many cell types in the body particularly
  those of the immune system

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Why do Vaccines Cause Scares?

• The vaccine-damaged child is a real child whose
  picture appears in the media
• The vaccine-saved children are only statistics
• Parents may feel that if all other children are
  vaccinated, theirs do not need to be.
• Pressure from anti-vaccine groups

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The Precautionary Principle

• Has no single agreed definition
• Often used as a reason for preferring inaction to
  action whenever there is uncertainty - i.e when
  in doubt do nowt
• However, particularly in public health, action
  and inaction are morally equivalent the
  precautionary principle is a cop out

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Absence of proof is not proof of absence

• When two events occur together, the difficulty in
  rejecting the hypothesis that one causes the
  other goes up as the frequency of the causal
  association goes down.
• I.e it is impossibly difficult to establish that
  a causal association never occurs
• But it is disreputable therefore to conclude
  that it does occur! the Paxman fallacy

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The Medias Dangerous Obsession with Maverick
Science

• Jacques Benveniste (Fr) Extreme dilution and
  memory in water to explain homeopathy
• Peter Duesberg (US) - HIV does not cause AIDS
• Alan Ebringer (UK) BSE is an autoimmune disease
  and therefore not contagious
• Arpad Pusztai (UK) GM potatoes poison rats
• Andrew Wakefield (UK) MMR gives rise to autism
  and colitis

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Other Objections to Vaccines

• Transmission blocking Vaccines no direct
  benefit to subject
• Human papilloma virus encourages promiscuity