Stomach flu is a highly contagious illness. However, the contagious period of this illness depends on the type of virus causing this condition. Norovirus is one of the main triggers of gastroenteritis among adults. This virus is contagious from the time patient first experiences the bouts of symptoms till three days after the recovery. Among children, rotaviruses are responsible for spreading this illness. Children attacked with rotaviruses become contagious two days before the symptoms start to show till ten days after the recovery.  

These highly contagious viruses can get easily transmitted even via a slight contact with the infected person. Leave alone sexual intercourse, this virus can gain entry in the body with mere contacts like handshakes, pat, kiss share of used utensils of the infected person. These viruses can even spread through fecal oral route. In this transmission, the fecal matter sticks to the hands of the person who changes the diaper or utilizes the bathroom of the ill person. It is alarming to note the contractual tendencies of this virus which can be most easily spread via a mere touch of the utilities belonging to the person suffering from stomach flu.  As soon as the new person ingests the virus, he starts feeling the same symptoms.