[Vaccinations in sports and recommendations for immunization against flu, hepatitis A and hepatitis B]

Intensive physical training in elite athletes can have an adverse effect on the immune system, and can increase the susceptibility to infectious diseases. The insult to the immune system includes the cellular, humoral and phagocitic pathways. The increased incidence of viral infections (in particularly of the upper respiratory tract) occurs mainly during periods of intense exercise training and competitions due to the combination of physiological and psychological stress. Other factors that may contribute to the decreased immunity and increased susceptibility to infections include eating disorders and nutritional deficiencies, jet lag, sleep deprivation, and lack of proper hygiene in shared food and sleeping quarters. For elite athletes, even a mild viral infection can be devastating due to loss of important training hours and/or compromise of competitive performance. Therefore, in addition to the goal of improving the athletes performance, another important responsibility/obligation of the staff working with athletes (physicians, nutritionists, physiotherapists, and psychologists), is to emphasize preventive medicine and maintenance of good health. In this article we define athletes, and especially elite athletes, as a population at risk of various infections, and recommend immunization against hepatitis A and B and a yearly immunization against influenza.