[Influenza virus].

Influenza virus is highly infectious and transmitted from human to human by droplet infection. Therefore, once the virus is brought into a hospital, this can lead to a severe outbreak of influenza among medical workers and inpatients, resulting in the failure of hospital functions. The fundamental protective measures against in-hospital infection include stopping the outbreak of influenza and minimizing the spread of infection when mass infection of influenza occurs in a hospital. Thus, it is vital that the infection control committee in each hospital prepares specific countermeasures against influenza infection reflecting the realities. As one such countermeasure, it is recommended is to give influenza vaccination to medical workers and patients before the illness becomes epidemic. Further, once an outbreak of influenza occurs in a hospital, administration of anti-influenza drugs to high-risk patients also needs to be considered.