Hello, My answer is that you did a good thing to send the sick pupil home as the infection could have spread more easily with him around the classroom. However, influenza A virus is very contagious and it is very likely that you and your pupils have been exposed to it. In order to minimize the risk of infection, you and your pupils should frequently wash their hands and maintain a high level of personal hygiene (the virus could spread through contact of contaminate hands with eyes, mouth, nose, i.e. organs with mucous membranes). Since, the virus can spread via air (through small droplets) then it is important to detect all other pupils with flu signs and symptoms (fever, cough, runny nose, chills, tiredness, headache, cough, loss of appetite, et cetera) and to send them home for some days. Feeding well and keeping an optimal hydration level is also important. Pupils can take some vitamin C supplements (100-200 mg per day) for about one week as this strengthens their immune system. There is not much else than you can do in this situation. CDC recommends vaccination as the best option to be protected from flu, but this decision has to be taken in the context of the situation in your country, severeness of flu, et cetera. Fortunately, most flu cases will experience mild forms of infection. Hope I have answered your query. Let me know if I can assist you further. Regards, Dr. Ervin Toçi