Evidence map›Paper›PMID 42023778›Full record

ArticleMedicine and science in sports and exercise2026

Infection as an Exertional Heat Illness Risk Factor: A Prospective Cohort Study.

Hayley C Tyson, Michael J Zurawlew, Megan R Robinson, Ross Hemingway, J O Corbett, Mike J Tipton, Alex A M Gould, Catherine Moore, Rachel Jones, Kathleen Pheasant and 4 more

Abstract read
In one paragraph

Article in Medicine and science in sports and exercise, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.

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0citing papers in PubMed
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1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

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Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

0 citing papers in PubMed.

No citing paper in PubMed yet.

4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

14 authors.

Hayley C TysonSchool of Sport and Exercise Sciences, Liverpool John Moores University, Liverpool, UNITED KINGDOM.
Michael J ZurawlewSchool of Sport and Exercise Sciences, Liverpool John Moores University, Liverpool, UNITED KINGDOM.
Megan R RobinsonSchool of Sport and Exercise Sciences, Liverpool John Moores University, Liverpool, UNITED KINGDOM.
Ross HemingwayMedical Centre, Commando Training Centre Royal Marines, Lympstone, UNITED KINGDOM.
J O CorbettExtreme Environments Laboratory, University of Portsmouth, Portsmouth, UNITED KINGDOM.
Mike J TiptonExtreme Environments Laboratory, University of Portsmouth, Portsmouth, UNITED KINGDOM.
Alex A M GouldExtreme Environments Laboratory, University of Portsmouth, Portsmouth, UNITED KINGDOM.
Catherine MooreWales Specialist Virology Centre, Public Health Wales, Cardiff, UNITED KINGDOM.
Rachel JonesWales Specialist Virology Centre, Public Health Wales, Cardiff, UNITED KINGDOM.
Kathleen PheasantWales Specialist Virology Centre, Public Health Wales, Cardiff, UNITED KINGDOM.
Alex J RawcliffeArmy Initial Training Command, UK Ministry of Defence, Upavon, UNITED KINGDOM.
Rachel M IzardDefence Science and Technology, Porton Down, UNITED KINGDOM.
Andrew J RobertsArmy Initial Training Command, UK Ministry of Defence, Upavon, UNITED KINGDOM.
Neil P WalshSchool of Sport and Exercise Sciences, Liverpool John Moores University, Liverpool, UNITED KINGDOM.

Funding

UK Ministry of Defence
6 · The paper itself

Abstract

purposeStrenuous physical activity for work or leisure increases the risk of exertional heat illness (EHI), which can be fatal. Respiratory infection may increase EHI risk, but empirical evidence is equivocal and relies upon clinical case reviews that lack objective measures and comparator controls. This prospective cohort study investigated the association between respiratory infection and EHI.

methodsN = 807 UK infantry recruits (M = 805/F = 2) completed a 6.4-mile loaded march between spring and fall (2021-2024, wet bulb globe temperature, 11.2°C ± 3.6°C). Participants completed the Jackson Common Cold Questionnaire on each of the 3 d preceding and before the loaded march on day 0. Additional measures included clinical pathology on throat swabs (day -3 and -1), serum C-reactive protein (CRP; day -1), and gastrointestinal temperature ( Tgi , day 0). EHI was classified as mild (exercise-induced headache, dizziness, or nausea) or severe (CNS disturbance plus hyperthermia and end-organ damage). Logistic regression examined the association between respiratory infection and EHI after full adjustment for widely considered EHI risk factors.

resultsN = 118 participants were classified as mild (15%) and N = 40 as severe EHI (5%). The likelihood of severe EHI was increased four-fold with respiratory infection symptoms on day -1 and 0 (OR = 4.09; 95% confidence intervals = 1.29-12.90, P = 0.016) and three-fold when restricting analysis to symptoms on day 0 (OR = 2.83, 95% confidence intervals = 1.02-7.86, P = 0.046). Participants with respiratory infection symptoms exhibited increased pathogen expression, systemic inflammation (CRP > 3 mg·L -1 ), and preloaded march Tgi (+0.3°C, P = 0.023). Respiratory infection symptoms were not associated with mild EHI susceptibility.

conclusionsOngoing respiratory infection was associated with an increased likelihood of severe EHI. Individuals at risk of EHI (e.g., athletes) should avoid strenuous physical activity when suffering respiratory infection symptoms.

Indexed as

Heat Stress DisordersPhysical ExertionRespiratory Tract InfectionsAdolescentC-Reactive ProteinFemaleHumansMaleProspective StudiesRisk FactorsUnited KingdomYoung AdultC-Reactive ProteinHEAT INJURYHEAT STRESSHEATSTROKEINFECTIONRESPIRATORY

Identifiers

PMID42023778
PMCPMC13446913

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LicenceCC BY-NC-ND
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Registered trials

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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.