Originally Posted By: Caoimh?n P. Connell
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Hello Mr. Cooke:
I was wondering when someone would raise the issue of this paper, but I?m astonished that it happened so quickly. I only received notice of the paper myself from Dr. Graham Atherton with an organization called ?The Aspergillus Website.?
You must move in some pretty eclectic circles, Mr. Cooke! The reason Dr. Atherton?s group is interested was due to the predominant genus identified in the pillows. However, I predicted that the paper would make a splash due to the presence of Scopulariopsis brevicaulis
in the pillows. So I was wrong on two accounts.
Woodcock?s work described in the paper is mostly observational. That is, to her credit, Woodcock interpreted very little based on the observations she made, since the data are not easily extrapolated to be germane to actual exposures, or physiological significance. Here are a few things to bear in mind when reading the paper.
Local climatic conditions will greatly alter the result of the loading in the pillows.
Local customs and societal norms will greatly alter the fungal loading in pillows.
The vacuum samples described in the paper are incomplete and are missing quantification (there is no way to use the data as presented to speak to the issue of exposure).
There is a paradigm used in assessing human exposures, it can be visualized as a triangle containing three elements 1) a source of a contaminant; 2) a susceptible recipient of the insult and, 3) a rout of migration from the source to the recipient. If one removes any one of these elements, there is limited significance in the remaining two. The paper identifies the susceptible recipient as patients with respiratory disease, and patients with asthma and sinusitis. Although it would appear that the source is definitively addressed, she addresses the source only superficially (and notes that there is such large sampling error, that interpretation is difficult). Finally, she honestly addresses the element of migration thusly: ?There is little correlation between reservoir and airborne fungal levels
?? and ?Thus, direct mucosal exposure to spores may not induce a typical allergic response, if the respiratory tract is normal and spore germination does not take place
Overall, the work is mostly a fun academic pursuit which adds another piece to the overall, and ever widening puzzle. However, I would have to disagree with Woodcock?s editorial that ?It is extraordinary that such a major unidentified source of fungal exposure has literally been staring us in the face
.? Since the concentrations of spores identified during the exercise appear to be pretty normal and not particularly ?major? at all.
Regarding the Aspergilli
, per se, disseminated aspergillosis is rare in individuals who are not immunocompromised. Generally speaking pathologic invasion is the epiphenomenona and not the primary pathology. Although aspergillosis is an extremely important opportunistic mycosis (usually seen as a nosocomial), but a rare primary mycosis in the absence of an underlying pathology that has degraded the immune system.
But that is not to say that the Aspergilli
are only found in immunocompromised individuals. A study by the Mayo Clinic, for example, found that 7% of healthy adults haboured Acremonium
, in their nasal passages; fully 50% of their healthy
study group were colonized with Alternaria
; 43% with Aspergilli
including A. clavatus, A. flavus
(which produces a powerful carcinogen) A. fumigatus
, and A niger
(all considered ?toxic" moulds by the fearmongers). Fully 7% of the healthy test subjects harboured the opportunistic pathogen Candida albicans
; 57% were colonized with Cladosporium
; 21% of the healthy volunteers nasal passages were colonized with members of the Penicillia
and the list goes on and on. However, these colonizations did not represent systemic invasions. I suspect, based on available information, that is likely that almost half of humans are colonized with the Aspergilli
as a fungal commensel.
Therefore, the question is not "Are fungal spores getting up your nose?" (to which the answer is ?Absolutely, yes?) but rather the question is ?Does it really matter?? or ?To what extent does it really matter??
To answer your question should we all change our pillows regularly? The paper does not speak to the issue of a time element. For all we know, based on the material presented, the mould spores were already in the pillows when they were purchased. Notice that there was no correlation between age of pillow and spore concentration. Furthermore, there did not appear to be statistically significant difference between spore counts and pillow type (synthetic v. feather) in spite of comments to the contrary.
Caoimh?n P. Connell
Forensic Industrial Hygienist
(The opinions expressed here are exclusively my personal opinions and do not necessarily reflect my professional opinion, opinion of my employer, agency, peers, or professional affiliates. The above post is for information only and does not reflect professional advice and is not intended to supercede the professional advice of others.)