Sport and infectious risk: a systematic review of the literature over 20 years.

The development of sports activities promoted as a health factor should not hide the increased risk for diseases, more particularly infections. A review of articles made over the last 20 years was made with a descriptive epidemiological purpose. The most marked risk is skin infection with methicillin-resistant community acquired Staphylococcus aureus (27.4% of the articles), followed by Tinea corporis and capitis (13.7%), and leptospirosis (11.7%). The risk of blood-borne infection seems low, and articles are rare (3.9%). The risk of disease with respiratory transmission (measles, meningococcal meningitis) must be taken into account. The effect of physical activity on the immune system depends on the type and duration of the work out: it seems to be beneficial for a workout of a moderate intensity, and deleterious for a sustained acute work out, or a period of intensive training. These periods of protection or susceptibility to infections are described as "open window" and "J curve". The only recommendations for prevention of sport-related infections arise from the frequency of skin infections and the severity of blood-borne infections. These recommendations are published by American and international sports authorities. The specificity of athletes' management is due to imperatives of competitiveness (maintaining physical performance) and the necessity of temporary eviction from sports, in case of contagiousness. The athletes must make sure their recommended vaccinations are up-to-date.