Q Fever

1

• Q Fever
• Paul McDermott/Mike Paton
• Biological Agents Unit
• Health Safety Executive

2
Route Map

• Background to Biological Agents Unit
• Outbreak Scotland 2006
• Issues raised
• Vaccination
• Emerging guidance

3
HSEs Biological Agents Unit

• Located at HQ in Bootle
• 14 x Specialist Health Safety Inspectors
• Microbiology Molecular Biology Disciplines
• Approximate total of 26 staff with UK wide remit

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Biological Agents Unit

• Hazardous Installations Directorate
• Chemicals
• Off-shore
• Specialised Industries explosives,
  gas/pipelines,
• mines, microbiology genetic modification (SI4)

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Biological Agents Unit

• Our work is aimed at ensuring that risks in the
  workplace from microbiological hazards are
  properly controlled
• Cover all aspects of GM and biotechnology related
  to human health and environmental safety
• Escape of Animal Pathogens from containment

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Q Fever - background

• highly infectious zoonosis - Coxiella burnetii
• widespread globally (including UK) among
  livestock - sheep, cattle and goats
• infection in animals is usually asymptomatic, but
  some abortions and stillbirths
• livestock - high concentrations of bacteria found
  in mammary glands, placental tissue and milk
  (lesser extent in urine and faeces)

7
Q fever Human Infection

• Q fever endemic in the UK 70 UK cases of Q
  fever per year
• actual number of cases may be 700 (1 of
  chronic atypical pneumonia)
• periodic outbreaks i.e. 4 major outbreaks in the
  UK over 17 years
• acute symptomatic human infection characterised
  by an influenza-like-illness (self limiting)
• chronic infection less common (10 cases) but
  can result in pneumonia or endocarditis
• clinical diagnosis of Q fever difficult
  (presentation as non-specific illness)
• highest incidence of infection in humans in the
  UK spring/early summer (lambing season)

8
Outbreaks in UK

• Birmingham outbreak (1989)
• similar wind borne spread outbreak from farms
  engaged in outdoor lambing and calving (147
  cases, 85 male, 90 adults)
• Newport outbreak (2002)
• 106 cases out of 250 workers from a factory ? due
  to release of spore-like particles from drilling
  into strawboard ceilings during renovation works
  in a cardboard box manufacturing plant
• Stirling, Scotland outbreak (2006)
• Meat processing plant outbreak thought to be
  related to a ewe that had aborted in May 2006.
  138 cases.
• Cheltenham (2008)
• 31 diagnosed cases in urban setting

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Route of transmission

• Usually inhalation of contaminated aerosols
• Windblown spore-like particles
• E.g. meat processing plants (Scotland 2006),
  straw materials embedded in constructions
  (Newport 2002)
• Ingestion of unpasteurised milk
• Little or no human to human spread (except
  possibly by inhalation of organisms contaminating
  clothing)
• Infectious dose very low ? 1 organism (in lab
  setting) may be different in field
• Incubation period 14-39 days (may be shorter if
  there is a high infectious dose)

10
Scottish Outbreak

• Late June 2006, local GPs reported increasing
  numbers of sick people from meat processing plant
  (by end of outbreak gt100 people confirmed
  positive)
• HSE asked to investigate possible source of
  legionella
• 17 July disease confirmed as Q Fever
• Environmental conditions very hot, dry weather
  in early summer
• Plant processed 2000 sheep per day (150 cows per
  day)
• No specific job/role within plant linked to
  exposure
• Source linked to sheep lairage and aborted foetus
  within exposure period

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Zoonoses Q fever
Canteen
Q-Fever Outbreak Scotland, June 2006
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Sheep Lairage
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Ventilation System
Lairage supply fans
14
Fire Door
lairage fire exit
Canteen entrance
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Contributory Factors

• General lack of understanding of the zoonotic
  risks
• Sheep aborted on site
• Site Layout (proximity animals/canteen)
• Ventilation (type operation)
• Weather (hot/dry/dusty access via fire door)
• Cleaning regime (infrequent)
• Throughput (2000 sheep per day)
• Cross contamination (hygiene measures/movement of
  staff)
• Animal welfare

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Action Taken

• Raise awareness of zoonoses risk (risk
  assessment, training)
• Re-design of lairage interior (assist cleaning
  not possible to relocate)
• New ventilation system fitted with an air
  scrubber
• Increased frequency cleaning of holding areas
• Procedures for disposal of birth products and
  other high risk material
• Hygiene procedures (segregation clean/dirty
  activities)

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Advisory Committee on Dangerous Pathogens (ACDP)

• ACDP provides scientific and technical advice to
  HSE and others on the risks from exposure
  infectious microorganisms independent,
  respected advice
• raised concerns over outbreak and emphasised need
  for further research - relationship between
  exposure, immunity and disease
• Supported the proportionate line of control taken
  by HSE
• Referred vaccination issue to JCVI
• Supported approach of raising awareness with
  industry

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Guidance for Employers

• HSE worked with British Meat Processors
  Association to develop guidance available on
  BMPA website
• Annual HSE/Defra press release related to risks
  to pregnant workers during spring lambing,
  calving and kidding (updated to reflect Q fever)
• VLA/HPA/Defra/HSE published a guidance note for
  farmers (Defra website)
• HSE articles in National Sheep Association
  magazine "Sheep Farmer" and British Veterinary
  Association magazine "In Practice
• HSE revised its agriculture supplement to reflect
  changes in working practices

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Health Safety ExecutiveField Operations
DirectorateBiological Agents UnitAgriculture
sector Occupational Health specialistsOccupation
al Hygiene specialists
Acknowledgements
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Thank you for your attention

• Any questions?

21
Q Fever Vaccine - Joint Committee for Vaccination
Immunisation (JCVI)

• HSE referred the matter to JCVI, who
• Considered data from Australia questioned
  supporting efficacy against UK strains
• Potential uses of vaccine e.g. for outbreak
  scenarios or prophylactic use or specific
  occupations (abbatoir, vets, farmers)
• Raised issue of severe reaction in vaccinees
  previously exposed to Q fever (severe reaction at
  inoculation site) and incidence pre-exposure (In
  NI, gt50 farmers seropositive 10lt urban
  population)
• Met with scientists from Australia to discuss
  vaccine data
• JCVI yet to reach decision hence Q-Vac still not
  licensed for use in UK