After initial reluctance masks have emerged as an important means of restricting the spread of SARS-CoV­2, the new coronavirus causing COVID-19 . Other simple measures are keeping a distance of at least 1 ½â€¯m from other persons and observing hygiene recommendations, including washing or even disinfecting the hands, coughing into the crook of the arm and remaining at home when sick . Combining the initial letters of the German words for the three measures (Abstand-Hygiene-Alltagsmaske, distance-hygiene-face mask) the acronym AHA was formed, a colloquial German word meaning that the speaker understood the information presented . This acronym was later extended by the letter``L", initial letter of``Lüften"meaning air ventilation for indoor rooms and arriving at AHA­L, recommended by the federal German Health Institute the Robert Koch Institute . In fact, masks including surgical masks and face coverings can form an effective barrier against the spread of the virus: protecting other people from droplets expelled from the throat of the speaker wearing a mask and even in part protecting the wearer from inhaling droplets emanating from other peoples' throats . Studies to find out if wearing masks might impose risks did not find essential problems: alterations of respiratory parameters due to an increased airway resistance remained within normal limits in healthy adults and even in asthmatics whose disease was well controlled; however, many adults expressed their unease with masks describing them as cumbersome and inconvenient . Emotional resistance against masks made it increasingly more difficult for them to use a mask . Efficient application of masks requires, in addition to a logical explanation of its effect, the evocation of empathy for vulnerable people who can be protected from catching a possibly deadly disease . In children there are very few data on adverse effects of wearing a mask although there is ample experience in children with serious diseases compromising defense against infectious agents acquired via respiratory mucus membranes; however, when using masks appropriately in children relevant adverse effects have not been reported and are not to be expected . Masks should only be used in children when they are healthy and awake and can remove the masks themselves anytime they like . Children 10 years or older can use masks efficiently when they have been informed beforehand appropriate to their age . Under these conditions they can also be obliged to wear masks in certain situations, for example while walking through the school building to their desk in class . To limit the period of wearing a mask normally they will be allowed to remove the mask when sitting in class and keeping their distance . Children in primary schools may use masks, but they should not be obliged to wear them and children in kindergartens should not use masks . This exemption of younger children does not expose school and kindergarten teachers to additional risks since the infectivity with SARS-CoV­2 is age-dependent and increases with age reaching adult values only after 12 years of age.