Generally, ordinary bronchitis is not contagious, but the cause of bronchitis can be bacterial or viral. If it is viral and it is caused by some special viruses, it is contagious. Like influenza virus, SARS virus, and some special avian influenza virus, all of these can cause infection. Generally, it is spread by coughing and coughing up sputum, and the droplets and sputum are transmitted to other people through the air. Therefore, once you have bronchitis, you should try to avoid going into the public environment to avoid the spread of the virus. Generally, common viruses are not contagious, and most bacterial infections are not contagious either.