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Study Type: Retrospective cohort study with methodological framework development and validation

Key Question: Can a novel three-component metric (DASC-LOT / S3) more precisely benchmark inpatient antimicrobial stewardship performance across hospitals than existing single-measure metrics?

Key Findings:

• Marked inter-hospital variation in antimicrobial use across 118 VHA hospitals: DASC/1,000 days present ranged 1,311–5,275; LOT/1,000 days present ranged 132–518
• The composite S3 metric (integrating initiation, duration, and spectrum) ranged from 0.703 to 1.572 across hospitals, with risk-adjustment models incorporating up to 116 patient-level variables
• Radar chart visualisation enabled hospital-specific identification of stewardship weaknesses across all three domains separately

Clinical Relevance: NHS stewardship teams currently rely heavily on Days of Therapy metrics; this framework could support more granular benchmarking and targeted interventions across NHS trusts.

Limitations: Derived exclusively from US Veterans Health Administration data, limiting direct generalisability to NHS inpatient populations and prescribing contexts.

Study Type: Retrospective cohort study

Key Question: Have modern antifungals reduced attributable, contributable, and all-cause mortality from culture-confirmed invasive aspergillosis (IA) in haematological malignancy patients over a 10-year period?

Key Findings:

• IA-attributable mortality showed a statistically meaningful decrease over the study period
• Contributable and all-cause mortality remained persistently high despite antifungal advances
• Findings suggest a potential "ceiling effect" of current antifungal therapy, with residual mortality driven by underlying host factors and competing causes

Clinical Relevance: For UK ID clinicians managing haematological malignancy patients — a high-burden group in NHS haematology-oncology settings — this signals that optimising antifungal choice alone is insufficient; host-directed strategies (e.g., immunomodulation, G-CSF, checkpoint inhibitor reversal) warrant prioritisation.

Limitations: The abstract provides insufficient detail to assess sample size, case ascertainment methodology, or confounding control, limiting critical appraisal.

Study Type: Retrospective cohort study

Key Question: Does initiating long-acting cabotegravir/rilpivirine (LA CAB/RPV) in viraemic people with HIV (PWH) result in comparable virological outcomes to those initiating whilst suppressed?

Key Findings:

• In two large U.S. cohorts (n=1,070), 96% of viraemic PWH achieved virological suppression at a median of 4 weeks post-initiation
• Virological blips and treatment failure occurred more frequently in those initiating LA CAB/RPV with detectable viraemia compared to suppressed initiators
• Findings suggest LA CAB/RPV can achieve suppression in viraemic patients but with a less favourable safety profile

Clinical Relevance: As NHS services increasingly offer LA CAB/RPV to PWH with adherence difficulties — who are often viraemic — this supports its use but highlights the need for enhanced virological monitoring post-initiation in this group.

Limitations: Retrospective design limits causal inference and baseline viraemia levels and resistance data are not detailed in the abstract.

Study Type: Systematic review

Key Question: What is the documented risk of Andes virus (ANDV) transmission to healthcare personnel (HCP) during nosocomial exposure events?

Key Findings:

• Across 7 nosocomial exposure events, 207 individuals were exposed (including 118 HCP), resulting in 8 HCP infections and 4 HCP deaths
• All described HCP infections occurred in the context of absent or inadequate PPE use and delayed implementation of transmission-based precautions
• Only 8 studies met inclusion criteria, reflecting sparse and inconsistently reported literature on healthcare-associated ANDV exposure

Clinical Relevance: With a WHO-declared multinational ANDV outbreak reported May 2026, UK ID teams and infection prevention services need current evidence to guide PPE protocols and risk assessments for potential imported cases presenting to NHS facilities.

Limitations: The small number of included studies (n=8) with heterogeneous reporting standards limits generalisability and may substantially underestimate true exposure and transmission rates.

Study Type: Retrospective cohort study

Key Question: Does hospital-level diagnostic excellence in sepsis — simultaneously minimising undertreatment and overtreatment — correlate with improved patient outcomes?

Key Findings:

• Only 4 of 20 hospitals met "Diagnostic Excellence" criteria; hospital performance on under- and overtreatment was negatively correlated (τ=−0.51), suggesting optimising one often compromises the other
• Treatment at Diagnostic Excellence hospitals was associated with significantly lower mortality/hospice discharge (aOR 0.61, 95%CI 0.41–0.90) and shorter LOS (−1.20 days, 95%CI −2.23 to −0.17)
• Antibiotic days were reduced at Diagnostic Excellence hospitals, though this did not reach significance (adjusted difference −0.62 days, p=0.07)

Clinical Relevance: For UK ID teams supporting sepsis stewardship, this supports the case that reducing both diagnostic delay and antibiotic overuse simultaneously — rather than prioritising one — is achievable and meaningfully improves outcomes.

Limitations: US health system data limits direct generalisability to NHS sepsis pathways and coding practices.

Study Type: Case series with genomic/phylogenetic analysis

Key Question: Which chikungunya virus lineage was circulating during the 2025 Bolivian outbreak, and what were its transmission dynamics?

Key Findings:

• Chikungunya virus was confirmed circulating in Bolivia during a 2025 outbreak via genomic surveillance
• Phylogenetic analysis identified the specific circulating lineage and characterised transmission dynamics (precise lineage designation and case numbers not reported in abstract)
• Findings support the value of sustained genomic surveillance for arbovirus emergence monitoring

Clinical Relevance: With increasing chikungunya importation into the UK from Latin America, understanding circulating lineages informs clinical suspicion, travel health advisory updates, and imported case management in NHS settings.

Limitations: The abstract provides insufficient detail on sample size, lineage identity, or epidemiological data to draw firm clinical conclusions — full publication required for meaningful interpretation.

Study Type: Prospective cohort study (household transmission study)

Key Question: What is the rate of symptomatic secondary household transmission of enterovirus D68 (EV-D68)?

Key Findings:

• Symptomatic secondary attack rate of 13.6% across 35 EV-D68 index households identified from 1,040 surveilled households
• Genomic sequencing confirmed household transmission, with 0–2 pairwise nucleotide differences between cases occurring 6–14 days apart
• Clustering of sequences within households supports person-to-person spread rather than independent community acquisition

Clinical Relevance: EV-D68 causes acute flaccid myelitis in children; quantifying household transmission risk informs public health guidance and infection control advice relevant to UK clinicians managing paediatric clusters or outbreak investigations.

Limitations: Symptomatic-only case ascertainment likely underestimates true secondary attack rate by missing asymptomatic infections.

Study Type: Case series (single case report)

Key Question: Can *Dirofilaria repens* cause ocular dirofilariasis acquired in the continental United States?

Key Findings:

• A subcutaneous eyelid nodule following an insect bite in a California patient was confirmed as *D. repens* infection on excision
• Diagnosis required combined morphological (histology) and molecular analysis; neither modality alone was sufficient for species-level identification
• This represents a notable occurrence of New World ocular dirofilariasis from a species predominantly associated with Old World (European/Asian) transmission

Clinical Relevance: UK clinicians should be alert to *D. repens* as a cause of periocular/subcutaneous nodules in returning travellers, but this case highlights emerging autochthonous transmission in North America, broadening the epidemiological context for travel history assessment.

Limitations: Single case report; no conclusions can be drawn regarding prevalence, vector competence, or transmission risk within the US.