evidence: Germany's Standing Committee on Vaccination (STIKO) has now recommended vaccination for all 12- to 17-year olds. The body is basing its new assessment on fresh data from the United States, where nearly 10 million children and adolescents have already been vaccinated. In a statement, the committee said the benefits would outweigh the very rare side effects. On August 2, the health ministers of the German states had already decided, contrary to generally allow everyone 12 and older to be vaccinated. On August 13 Health Minister Jens Spahn tweeted that one in four from this age group have already been vaccinated at least once. [...] In the United States and Canada, however, BioNTech-Pfizer's vaccine has been used in adolescents and older children since May. In the US alone, more than 4.4 million 12- to 15-year-olds have already been fully vaccinated, and nearly 3.8 million have received a first dose. [...] Children's immune systems react differently to vaccines than those of teenagers and adults, according to experts. Finding the safest and most effective vaccine dose is thus essential. BioNTech-Pfizer and Moderna are currently conducting studies with children aged 6 to 11. AstraZeneca is testing its vaccine on younger children, but results are not yet available.