In accordance with the German Infection Protection Law (Infektionsschutzgesetzt) it is mandatory that parents/guardians inform the school in case of any infectious diseases. In collaboration with the regional health board (Gesundheitsbehörde) this is a precondition to avoid or at least limit the spreading of an infectious illness. School attendance is then only permitted with a doctor's certificate. If illnesses occur that are listed in the Infection Protection Law, all parents of the class community will be informed anonymously.
COVID-19 - When are you allowed to come to school?
How can you protect yourself from infectious diseases?
To prevent the spread of respiratory diseases, good hand hygiene, and a correct coughing and sneezing etiquette should be observed. These measures are always advisable during the influenza season.
Parents are asked not to send sick children to school.
https://www.infektionsschutz.de/hygienetipps/hygiene-beim-husten-und-niesen/ (Coughing and sneezing hygiene, in German)
https://www.infektionsschutz.de/mediathek/filme/filme-zu-hygiene-im-krankheitsfall/ (Videos, in German)