List bacterial strains caused by contaminated water supply at queen elizabeth hospital glasgow
Executive summary
NHS Greater Glasgow and Clyde has accepted that faults in the Queen Elizabeth University Hospital (QEUH) water system "probably" caused serious infections in paediatric cancer patients, and reporting identifies Stenotrophomonas maltophilia as a named organism implicated in at least one fatal case (Milly Main) [1] [2] [3]. Public inquiries and Health Protection Scotland documents describe a wider pattern of Gram‑negative and environmental organisms discovered at tap outlets and in patient blood cultures, but the official testing record is mixed and does not present a simple, exhaustive list of strains isolated from the hospital water supply [4] [5].
1. The headline strain: Stenotrophomonas maltophilia named in fatal cases
Multiple news reports and inquiry submissions single out Stenotrophomonas maltophilia as a significant organism in the QEUH scandal: 10‑year‑old Milly Main contracted and died after infection with S. maltophilia while being treated for leukaemia, and families and prosecutors have cited that organism when linking clinical infections to the hospital environment [3] [6] [7]. NHS Greater Glasgow and Clyde’s late admission that water system problems "probably" caused infections has reinforced public focus on this environmental, opportunistic Gram‑negative bacterium [2] [1].
2. A cluster of "Gram‑negative and unusual environmental bacteria" beyond a single species
Official investigation reports and oversight documents describe outbreaks involving multiple Gram‑negative and environmental bacteria rather than a single pathogen; Health Protection Scotland and the oversight board’s report say a range of blood infections were caused by 12 separate types of bacteria and fungi in paediatric patients, and that “Gram‑negative and unusual environmental bacteria” were found in outlets and clinical samples [8] [4]. The oversight report also notes discovery of Gram‑negative organisms in tap outlets and the role of biofilm formation in flow regulators as a plausible mechanism for outlet contamination [4] [9].
3. Conflicting test results and the limits of water sampling
The official record shows inconsistent microbiology from environmental sampling: the oversight report records 151 water samples between March and November 2017 that were negative for Elizabethkingia, coliforms, Pseudomonas spp., Legionella and Stenotrophomonas maltophilia within the main water system, even while unusual organisms were being recovered from outlets and patients [4]. Investigators and clinicians warned that negative bulk water tests do not exclude outlet‑level contamination caused by biofilms, flow straightener design, or local plumbing defects—factors explicitly discussed in the government and NHS reports [4] [9].
4. How the reporting and inquiries frame the microbial picture
Contemporary reporting (The Guardian, BBC, STV, Glasgow Times, Daily Record, Sky) emphasizes both named clinical isolates—most prominently S. maltophilia—and broader environmental microbial findings, while inquiry material and Health Protection Scotland analyses stress complexity: multiple species, outlet‑specific colonisation, biofilm dynamics, and sampling limitations [10] [11] [1] [4] [5]. That framing explains why public accounts often cite a few striking names (like S. maltophilia) while technical documents describe a spectrum of Gram‑negative and environmental organisms without publishing a single consolidated species list linked categorically to the primary water mains [8] [4].
5. What can be stated with confidence and what remains unclear
It is factual that Stenotrophomonas maltophilia was identified in at least one fatal patient infection and that the health board has admitted water‑system problems probably contributed to infections [6] [2] [1]. It is also factual that investigators documented multiple different bacteria and fungi in affected patients and found Gram‑negative organisms at tap outlets, and that bulk water sampling produced many negative results for named pathogens—leaving a complex evidential picture [8] [4]. What public sources do not provide is a definitive, openly published catalogue tying each named species to specific water sampling locations across the campus; the inquiry material and oversight reports make clear why attribution is epidemiologically and technically challenging [4] [9].