The aim of the study was to evaluate the safety
of influenza vaccines for the northern and southern hemispheres in Polish elite athletes
participating in the Rio 2016 Olympics.
Prospective, observational, cohort study.
vaccinated only with the northern hemisphere vaccine; 98 athletes
received the southern hemisphere vaccine alone, whereas 39 athletes
were vaccinated with both vaccines.
were vaccinated with a trivalent, inactivated influenza vaccine recommended for the northern hemisphere 2015/2016 and then with the vaccine recommended for the southern hemisphere 2016. Athletes
kept a diary of adverse events and effects (if any) on training
for 6 days after vaccination.
Main Outcome Measures:
The percentage of general and local adverse events, number of lost or modified training
Significantly more local adverse events (pain and redness) were found in the group immunized with the vaccine for the northern hemisphere. There were no differences in the frequency of general adverse events and influence on training
between groups. Of total 273 athletes
who had 1911 training
days during 6 days after vaccination, 6 athletes
(2.2%) lost 13 training
days (0.7%) and 16 athletes
(5.9%) had to modify 34 (1.7%) training
days within first 2 days after vaccination.
tolerated influenza immunization well. If they are going to travel to the other hemisphere during the influenza season, the use of the second influenza vaccine should be advised. Athletes
should anticipate modification of trainings for 2 days after vaccination.