Ewan Harrison

Ewan Harrison

@ewanharrison.bsky.social

Microbiologist at the Wellcome Sanger Institute and University of Cambridge.

376 followers544 following26 posts

Ewan Harrison reposted

The variation and problems encountered demonstrate the importance of QC and QA in AMR testing and that is important to consider when analysing genomics data for AMR. Huge thanks to the team at NICD Charm.

Ewan Harrison reposted

Lovely work driven by Lizzie Ledger in the group: a new but druggable mechanism by which Staphs produce biofilm using components of human serum. First polysaccharides, then protein, then eDNA, now lipids too! bsky.app/profile/bior...

bioRxiv Microbiology@biorxiv-microbiol.bsky.social

Human serum triglycerides promote Staphylococcus aureus biofilm formation and antibiotic tolerance https://www.biorxiv.org/content/10.64898/2026.03.05.709992v1

Ewan Harrison reposted

Great to share the latest work from our group and collaborators. First CARRIAGE study paper led by @drdaggarwal.bsky.social and the heroic efforts of Katie Bellis and Beth Blane in the lab plus all the team at @cambridge-ceu.bsky.social Huge thanks goes to the 22,000 participants of the study

Wellcome Sanger Institute@sangerinstitute.bsky.social

People who persistently carry the bacterium Staphylococcus aureus have a much less diverse community of bacteria in their nose, while certain species may help keep it out. 🦠 These findings offer insight into who may be at higher risk of infection. 👇 www.sanger.ac.uk/news_item/la...

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We also found some interesting differences in the nasal microbiome between men and women, and between the strains of S. aureus that are present at high abundance. This all now needs evaluation in larger numbers and different human populations.

Great to share the latest work from our group and collaborators. First CARRIAGE study paper led by @drdaggarwal.bsky.social and the heroic efforts of Katie Bellis and Beth Blane in the lab plus all the team at @cambridge-ceu.bsky.social Huge thanks goes to the 22,000 participants of the study

Wellcome Sanger Institute@sangerinstitute.bsky.social

People who persistently carry the bacterium Staphylococcus aureus have a much less diverse community of bacteria in their nose, while certain species may help keep it out. 🦠 These findings offer insight into who may be at higher risk of infection. 👇 www.sanger.ac.uk/news_item/la...

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This confirms previous data and hypothesis that ‘ intermittent carriers’ (people who will sometime be positive for S. aureus and sometimes not) aren’t a distinct biological group - rather they have microbiomes just like persistent or non-carriers.

We found that people less likely to carry S. aureus tended to have more of Dolosigranulum pigrum, Staphylococcus epidermidis and Moraxella catarrhalis. These bacteria may crowd out, kill or compete with S. aureus, but that requires further study.

Great to share the latest work from our group and collaborators. First CARRIAGE study paper led by @drdaggarwal.bsky.social and the heroic efforts of Katie Bellis and Beth Blane in the lab plus all the team at @cambridge-ceu.bsky.social Huge thanks goes to the 22,000 participants of the study

Wellcome Sanger Institute@sangerinstitute.bsky.social

People who persistently carry the bacterium Staphylococcus aureus have a much less diverse community of bacteria in their nose, while certain species may help keep it out. 🦠 These findings offer insight into who may be at higher risk of infection. 👇 www.sanger.ac.uk/news_item/la...

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Combining nasal microbiome data and culture data we show when S. aureus is present, it often dominates. We can group the nasal microbiome into two major patterns: 1. S. aureus dominated with overall low microbial diversity 2. S. aureus is rare, and there is a greater diversity of other bacteria.

Great to share the latest work from our group and collaborators. First CARRIAGE study paper led by @drdaggarwal.bsky.social and the heroic efforts of Katie Bellis and Beth Blane in the lab plus all the team at @cambridge-ceu.bsky.social Huge thanks goes to the 22,000 participants of the study

Wellcome Sanger Institute@sangerinstitute.bsky.social

People who persistently carry the bacterium Staphylococcus aureus have a much less diverse community of bacteria in their nose, while certain species may help keep it out. 🦠 These findings offer insight into who may be at higher risk of infection. 👇 www.sanger.ac.uk/news_item/la...

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Over the last 70yrs using nasal swabs and culture it has been established that some people are persistently colonised by Staphylococcus aureus, while others never are - and third group are positive from time to time (intermittent carriers). We investigated the nasal microbiome in these groups

Great to share the latest work from our group and collaborators. First CARRIAGE study paper led by @drdaggarwal.bsky.social and the heroic efforts of Katie Bellis and Beth Blane in the lab plus all the team at @cambridge-ceu.bsky.social Huge thanks goes to the 22,000 participants of the study

Wellcome Sanger Institute@sangerinstitute.bsky.social

People who persistently carry the bacterium Staphylococcus aureus have a much less diverse community of bacteria in their nose, while certain species may help keep it out. 🦠 These findings offer insight into who may be at higher risk of infection. 👇 www.sanger.ac.uk/news_item/la...

Ewan Harrison reposted

Really pleased to share the first paper to come out of the lab. We found that hospital patients were frequently colonised with P. aeruginosa and that the same clone was shared between the gut and the lung. The phylogenies indicate that the clones moved from lung->gut www.nature.com/articles/s41...

nature.comHigh frequency body site translocation of nosocomial Pseudomonas aeruginosa - Nature CommunicationsHere, the authors report within-host diversity and body site translocation dynamics in hospital samples of Pseudomonas aeruginosa and reveal that body site sharing was likely due to within-patient tra...

Ewan Harrison reposted

Ewan Harrison reposted

Samples from 1917 have helped identify the genetic culprits responsible for the spread of treatment-resistant infections 🔎 By mapping plasmid evolution since the pre-antibiotic era, experts found that a minority of plasmids cause most of the multidrug resistance in the world 🧵

Ewan Harrison reposted

Ewan Harrison reposted

📢Today Pathoplexus announces the inclusion of 2 new viral pathogens: RSV (A & B) and HMPV. These respiratory viruses cause a serious health burden, particularly in infants & the vulnerable, & Pathoplexus aims to support sequence sharing to improve understanding & response. 1/4

Happy to share our first preprint looking at the nasal microbiome in ~1000 healthy adults from the CARRIAGE study of 20,000 healthy blood donors to understand nasal colonisation by Staphylococcus aureus. Ten years in the making! doi.org/10.21203/rs....

doi.orgThe nasal microbiome redefines Staphylococcus aureus colonisationStaphylococcus aureus colonises the nose in humans, with individuals defined as persistent, intermittent or non-carriers. Unlike the gut microbiome, the nasal microbiome has not been studied in large ...

Ewan Harrison reposted

Ewan Harrison reposted

Ewan Harrison reposted

There were more than 125,000 measles cases in the WHO European region in 2024 - the highest number since 1997! 38 deaths have been reported so far, every single one of them preventable. Worth remembering this also as we report on the measles outbreak in the US. 🧪 #IDsky

Ewan Harrison reposted

Weeks ago I highlighted the false balance of “if only scientists could communicate better”. One OpEd writer kindly reached out to me and I want to share my main response to them because I find it remarkable that people still can’t see what we are now all seeing has been under way for years. 🧵👇

We reveal that genes involved in nitrogen metabolism showed the strongest signal of adaption. As well as antibiotic resistance, riboflavin biosynthesis and quorum sensing regulation (amongst others).

To understand the selective pressures that S. aureus experiences during colonisation, we analysed ~7000 S. aureus genomes from ~1500 individuals to identify protein altering mutations that were enriched.

Ewan Harrison reposted

Frustrating - I reviewed a paper that was highly problematic, mainly in scientific rigour undermining most of the conclusions, so I recommend Reject. However the editor decides to Revise presumably due to the more positive comments from reviewer 2... /1