Level of respiratory protection against influenza virus

Sir, the recent report on influenza is very interesting [1]. Heuer et al. reported that “The three tested filters retained the virus input, indicating that their use in the breathing systems of intubated and mechanically ventilated patients can reduce the risk of spreading the virus to the breathing system and the ambient air." [1] In fact, the management of the intubation in the era of influenza outbreak is a topic to be discussed. The protective tool to clear out the spreading of influenza virus is very important. It should be noted that regular replacement of the used filter has to be done because the contaminated filters can be the source for viral spreading [2]. In addition to the filters, the practitioners have to use self-protective device. Simonds et al. noted that “health-care workers providing non-invasive ventilation (NIV) and chest physiotherapy, working within 1 m of an infected patient should have a higher level of respiratory protection" [3].