Part of beneficial host response?BMJ 2010; 340 doi: https://doi.org/10.1136/bmj.c450 (Published 26 January 2010) Cite this as: BMJ 2010;340:c450
- Garth Dixon, consultant microbiologist and honorary senior lecturer1,
- Clare Booth, research assistant2,
- Elizabeth Price, honorary consultant microbiologist3,
- Roger Westran, senior biomedical scientist3,
- Malcolm Turner, professor of molecular immunology2,
- Nigel Klein, professor of infection and immunity1
- 1Infectious Diseases and Microbiology Unit, Institute of Child Health, University College London, London WC1N 1EH
- 2Immunobiology Unit, Institute of Child Health, University College London, London WC1N 1EH
- 3Department of Medical Microbiology, Barts and the London NHS Trust, Pathology Pharmacy Building, London E1 2ES
Fowler comments on the value of a raised temperature to combat flu.1 Fever may also be necessary for optimal defence against bacterial infections.2 We explored this possibility for meningococcal disease.
We diluted a suspension of an isolate of Neisseria meningitidis B to approximately 109 colony forming units/ml. We inoculated 500 µl suspension into supplemented proteose peptone 9.5 ml in duplicate and incubated one tube of each diluted suspension in a shaking water bath (120 rpm) at 37°C or 40°C. We measured optical density at 540 nm as an indicator of growth in a 100 µl sample every hour. We subsequently determined survival of N meningitidis in whole blood at different temperatures according to the method of Ison et al.3
The figure⇓ shows that growth in proteose peptone was retarded at 40°C compared with 37°C after 4 hours of incubation, corresponding to around the mid-log phase of growth (Student’s paired t test, P=0.015). In addition, after 4 hours almost a log fewer bacteria were growing in whole blood incubated at 40°C compared with at 37°C (Student’s paired t test, P=0.02).
Both experiments showed reduced meningococcal growth at higher temperatures, supporting the idea that fever is a beneficial host response.4 Antipyretic treatment may be counterproductive. For example, controlling bacterial proliferation in early meningococcal disease may be critical since the bacterial load at presentation is a major determinant of clinical outcome.5 Fever may have an important role in this process.
Cite this as: BMJ 2010;340:c450
Research at the Institute of Child Health and Great Ormond Street Hospital for Children National Health Service (NHS) Trust benefits from research and development funding received from the UK NHS Executive. CB was supported by the Medical Research Council of the United Kingdom, and was research assistant at both the Infectious Diseases and Microbiology Unit and the Immunobiology Unit at the Institute of Child Health.
Competing interests: None declared.