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#Mycology thread on our new Microbial Genomics paper on WGS of clinical & environmental #Mucorales after #mucormycosis cluster in #transplant pts. 72 isolates from 72 isolates from med center & community cases, /1 @SundermannAJ @mhn5pittedu1 @MicrobioSoc https://www.microbiologyresearch.org/content/journal/mgen/10.1099/mgen.0.000473?originator=authorOffprint&identity=184117×tamp=20211127165209&signature=c5f15b635d006360acbb02633051e07b
cases, hospital environs, Pgh region. A) Epi story: 4 cases in 10 mos in SOT pts. 3 virtual identical R. microsporus from 2 pts 7 mos apart in adjoining hospitals separated by city block, intervening building & walkway, suggesting common source or wide clonal distribution in /2
region. Linen heavily contaminated at laundry & upon arrival at med center dock (shared by 2 hospitals). Laundry remediation virtually eliminated contamination, no further hospital cases. See our prior linen surveillance story below. Linen-associated /3 https://academic.oup.com/cid/article/68/5/850/5123975Linen
R. microsporus strain most closely related to pt stains, but distinct by GC%, genome size. Same phylogenetic clade (clade #1, red box, P3,6: SOT pts, L32: linen, P9: control pt) also had more distant regional strain. R corymbifera (clade 4) & R delemar (clade 5) from other SOT /4
from other SOT genetically distinct from linen & environmental strains. Conclusions: epi investigation strongly points to linen, no WGS smoking gun. Can't beat shoe leather epi! Gotta collect & WGS multiple strains at time of cases. Linens & hospitals home to diverse Mucorales /5
communities. B) Other stories: Hospital Mucorales include clades recovered over 20 mos studied here, others that were transient. ITS & D1/D2 species identification not necessarily consistent with WGS species identification, so many clinical strains may be mis-identified! Core /6
genome phylogenetics give false identity be/ strains. Need comprehensive global comparison of GC%, protein families, genome sizes, pangenome analyses! Within species, massive paralog expansions/contractions, differences in genome size (even w vitrually identical core phylogeny /7
Other than 3 isolates from 2 SOT pts, all other strains could be distinguished by WGS. Lots of other cool pearls--read the paper! Also, hospitals may want to know what fungi are on their linens. We keep immunsuppressed pts in controlled environments, then give them dirty linen!
Forgot to attach some of comprehensive genome analyses, since it was ton of work to make these Venn diagrams. More papers on this story to come from @mhn5pittedu1, who directed massive 3+ yr Pgh hospital, laundry & nationwide hospital surveillance study, @SundermannAJ & team.
Since I was asked off-line: In general, hospital strains. though diverse, are more closely related to ea other than to regional or national (from Fungus Testing Lab in San Antonio) strains. Regional are more closely related to one another than to national controls. @MicrobioSoc
