Airborne fungi infections

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Airborne fungi infections

• Dr David W. Denning FRCP FRCPath
• Scientific Advisor to the Fungal Research Trust
• Clinician, Wythenshawe Hospital
• Head, Antifungal Testing Laboratory
• Faculty, University of Manchester
• WWW.aspergillus.man.ac.uk

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Airborne fungal infections

• Fungi are all around us in the air and yeasts (ie
  Candida) live in our guts
• Exposure to fungi is one of lifes certainties

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• Introductions

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Aspergillus 38 species have caused disease
Common in the environment
Aspergillus fumigatus
Aspergillus niger


www.aspergillus.man.ac.uk
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Aspergillus spore head
Spores 3uM across (i.e. easily are drawn into the
lungs)
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The supporting cast
Alternaria
Cladosporium
Penicillium
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Airborne fungi and their diseases

• Aspergillus
• Alternaria
• Cladosporium
• Penicillium
• Others

Invasive (life- threatening) infection Chronic
infection Allergy/asthma
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• Where are airborne fungi found?
• Outside air
• Home
• Hospital

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Aspergillus and compost
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Airborne fungi and pillows
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Airborne fungi and pillows
Feather pillow
Synthetic pillow
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Fungus in the bedroom
We have been examining pillows for fungi
Other common species were other Aspergillus
spp., Penicillium spp., Cladosporium spp. What
this means is that each old pillow contains 1
million fungal spores
Woodcock et al, Allergy 2005 In press
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Airborne fungi on clothes and fabrics
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Airborne fungi

• Common sources of airborne fungi
• Outside air especially Cladosporium
• After thunderstorms esp Alternaria
• In homes esp Aspergillus and outdoor
  fungi
• In hospitals esp Aspergillus

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Airborne fungi
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Airborne fungi and hospital construction
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Airborne fungi and hospital computers
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Airborne fungi on air conditioning systems in
hospital (intake ducts)
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Airborne fungi in hospital
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Airborne fungi in hospital
Outside room
Inside room
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Airborne fungi in hospital
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Airborne fungi in hospital after continous air
filtration
Outside room
Inside room
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• Invasive aspergillosis
• Chronic pulmonary aspergillosis
• Allergic aspergillosis
• ABPA
• Severe asthma association

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• Invasive aspergillosis
• Chronic pulmonary aspergillosis
• Allergic aspergillosis
• ABPA
• Severe asthma association

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Life-threatening aspergillosis
24 year old with genetic immune defect
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Predicted numbers of invasive Aspergillus
infections in the UK
Actual cases ? ? ? ? ? ? ? ?
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• Invasive aspergillosis
• Chronic pulmonary aspergillosis
• Allergic aspergillosis
• ABPA
• Severe asthma association

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Chronic pulmonary aspergillosis
January 2001
30 year old smoker with no immune defect
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Chronic pulmonary aspergillosis
April 2003
30 year old smoker with no immune defect
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Predicted numbers of chronic lung Aspergillus
infections in the UK
Those at risk Prior TB (?5) Sarcoidosis with
cavitation (12 of all) Lung damage
(pneumothorax etc) Prevalence rate in the UK
???? 200-1000 cases Incurable
currently (require
life-long treatment)
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• Invasive aspergillosis
• Chronic pulmonary aspergillosis
• Allergic aspergillosis
• ABPA
• Severe asthma association

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ABPA
Plug in airways
Airway clear after removal
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ABPA with airway obstruction
Mild asthma with shortness of breath
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Predicted numbers of ABPA patients in the UK
Those at risk Adults with asthma 4,100,000 on
treatment Cystic fibrosis 2,700
adults Prevalence rate in the UK 1 of
asthmatics 41,000 patients 15 adult CF
patients 405 patients
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• Invasive aspergillosis
• Chronic pulmonary aspergillosis
• Allergic aspergillosis
• ABPA
• Severe asthma association

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Severe asthma with fungal sensitisation
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Aspergillus fumigatus
Alternaria
Cladosporium
Candida
Penicillium
Negative Control
Grass
Histamine
House dust mite
Cat
Dog
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Spore counts and asthma attacks and admission to
hospital

• All circumstantial evidence
• Thunderstorm asthma linked to Alternaria
• Asthma deaths (Chicago) linked to high ambient
  spores counts and season (summer autumn) when
  spore counts highest
• Asthma hospital admission linked to high ambient
  spore counts (Derby, New Orleans, Ottawa)
• Asthma hospital attendance linked to high spore
  counts, but not pollen counts (Canada)
• Asthma symptoms increased on days of high spore
  counts (California, Pennsylvania)

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Fungus at home

• Environmental data
• Mouldy housing associated with worse asthma
• Wheezing in children associated with damp housing
• Mouldy and damp school associated with asthma
  symptoms and emergency room visits
• Highest concentration of Aspergillus fumigatus is
  at home

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Airborne fungal fragments
Fungal fragment
Diffusing allergen leeching out of fungus in
contact with liquid
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Hospital admission with asthmatic attacks and
mould allergy
Allergen Asthma, no admission (n82) Asthma,
2 admission (n46) House dust mite 56
67 Grass pollen 46 63 Cat 37
59 Dog 18 48 Any non fungal
allergen 70 74
ODriscoll et al, BMC Pulm Med 2005184
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Hospital admission with asthmatic attacks and
mould allergy
Allergen Asthma, no admission (n82)
Asthma, 2 admission (n46) Aspergillus 7
37 Alternaria 5 26
Cladosporium 1 41 Penicillium 2
30 Candida 10 33 Any fungal
allergen 16 76
ODriscoll et al, BMC Pulm Med 2005184
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Severe asthma and moulds
Severe asthma 235 (21) of all asthmatics
Odds ratio
Increasing frequency of fungal skin test
positivity in severe asthma
Zureik et al, Br Med J 2002325411
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Predicted numbers of severe asthmatics with
fungal sensitisation in the UK
Those at risk Adults with asthma 4,100,000 on
treatment Severe asthma 5-21 Mould
allergic 35-50 Prevalence rate in the
UK Lower number 71,750 patients Upper
number 430,500 patients 40,000 adults
admitted to hospital in the UK each year with
asthma Admissions reduced to 25 with antifungal
therapy in 14 patients (pre antifungal - 1.63
admissions per year, post antifungal 0.4)
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Conclusions

• Fungi are all around us in the air
• Exposure to airborne fungi is one of lifes
  certainties
• Many people in the UK have infection or allergy
  due to fungi, and additional research and care is
  required for these patients.
• Ascertainment of national caseload would be
  useful