Great Ormond Street's same-day metagenomics changes care for 29% of ICU samples

Great Ormond Street Hospital (GOSH) has reported the first same-day pan-microbial metagenomics service for children, run in its intensive care units during the 2024-25 winter, with results published in The Lancet Microbe on 16 October 2026 ¹. The service uses a respiratory pathway first built at Guy's and St Thomas' NHS Foundation Trust and forms part of the NHS Respiratory Metagenomics Network, which the Department for Science, Innovation and Technology (DSIT) funds to extend rapid testing to hospitals across the country ¹.

What the evaluation found

Metagenomics sequences all of the genetic material in a sample, so laboratories can look for bacteria, viruses and fungi at once instead of testing for a short list of suspected pathogens chosen in advance ¹. The GOSH team tested 177 respiratory samples taken from 122 critically ill children ¹.

The results changed clinical management for 29% of samples ¹. For 26%, they shaped antimicrobial prescribing: an antibiotic was started, stopped or switched, or clinicians gained confidence that the existing treatment was right ¹. The service picked up 50 organisms that routine diagnostics had not found, and further testing confirmed every one of them ¹.

The hospital described one case in which testing on a child receiving ECMO identified Mycoplasma pneumoniae and showed it was resistant to the antibiotic already prescribed, something standard methods would not have revealed ¹.

What it means for the market

The main finding for NHS buyers is that the pathway transferred. Julianne Brown, who heads the GOSH metagenomics service, said the work showed rapid respiratory metagenomics "can be successfully transferred from the centre where it was developed and embedded into routine clinical care for children" ¹. That matters for a national network: each new site does not have to build its own method, which shortens the route from one specialist laboratory to many hospitals.

Guy's and St Thomas' says it leads the network's deployment and that the GOSH work is evidence for offering the test to children across the UK, including at the Evelina London Children's Hospital and paediatric units across its network of more than 20 hospital sites ¹. For sequencing, informatics and laboratory suppliers, a DSIT-funded national rollout points to growing NHS demand for rapid pathogen sequencing and the data pipelines behind it, though the source gives no figures on spending, volumes or contracts ¹.

The clinical team also framed the service as an antimicrobial stewardship tool, because it helps stop treatments that will not work, and as a pandemic preparedness asset that could flag unusual or emerging infections ¹. Those two arguments are the ones most likely to carry weight with commissioners and with the government departments funding the network.

Caveats

The evidence comes from a single specialist children's hospital over one winter season, and the sample of 122 patients is modest ¹. The report gives no information on cost per test, turnaround time in hours, or outcomes such as length of stay or survival, so the economic case for wider adoption is not yet set out in the source ¹. The figures come from the hospital's account of the study; the full methods and limitations are in the Lancet Microbe paper ¹.

The next step named is wider paediatric access, beginning with the Evelina London Children's Hospital and the Guy's and St Thomas' paediatric network ¹.