Related Experiment Video
Updated: Dec 2, 2025
High-throughput Detection Method for Influenza Virus
Published on: February 4, 2012
Detection of influenza virus in air samples of patient rooms
A Chamseddine1, N Soudani2, Z Kanafani3
1Department of Civil and Environmental Engineering, American University of Beirut, Beirut, Lebanon.
Background:
Understanding the transmission and dispersal of influenza virus and respiratory syncytial virus (RSV) via aerosols is essential for the development of preventative measures in hospital environments and healthcare facilities.
Methods:
During the 2017-2018 influenza season, patients with confirmed influenza or RSV infections were enrolled. Room air samples were collected close (0.30 m) to and distant (2.20 m) from patients' heads. Real-time polymerase chain reaction was used to detect and quantify viral particles in the air samples. The plaque assay was used to determine the infectiousness of the detected viruses.
Findings:
Fifty-one air samples were collected from the rooms of 29 patients with laboratory-confirmed influenza; 51% of the samples tested positive for influenza A virus (IAV). Among the IAV-positive patients, 65% were emitters (had at least one positive air sample), reflecting a higher risk of nosocomial transmission compared with non-emitters. The majority (61.5%) of the IAV-positive air samples were collected 0.3 m from a patient's head, while the remaining IAV-positive air samples were collected 2.2 m from a patient's head. The positivity rate of IAV in air samples was influenced by distance from the patient's head and day of sample collection after hospital admission. Only three patients with RSV infection were recruited and none of them were emitters.
Conclusion:
Influenza virus can be aerosolized beyond 1 m in patient rooms, which is the distance considered to be safe by infection control practices. Further investigations are needed to determine the extent of infectivity of aerosolized virus particles.
Insights
Influenza virus aerosols can spread over 1 meter from patients, challenging current infection control assumptions. This highlights the need for enhanced airborne precautions in healthcare settings to prevent nosocomial transmission.
Area of Science:
- Infectious Diseases
- Epidemiology
- Environmental Health
Background:
- Understanding aerosol transmission of influenza virus and respiratory syncytial virus (RSV) is critical for hospital infection control.
- Current preventative measures may not fully address airborne spread in healthcare facilities.
Purpose of the Study:
- To investigate the aerosol dispersal of influenza A virus (IAV) and RSV in patient rooms.
- To assess the risk of nosocomial transmission based on viral aerosolization.
Main Methods:
- Air samples were collected at 0.3m and 2.2m from patients with confirmed influenza or RSV.
- Real-time polymerase chain reaction (PCR) was used to detect viral RNA.
- Plaque assays determined the infectiousness of detected viruses.
Main Results:
- 51% of air samples from influenza patients were positive for IAV.
- 65% of IAV-positive patients were "emitters," shedding virus in aerosols.
- IAV was detected up to 2.2m from patients, indicating airborne spread beyond 1 meter.
Conclusions:
- Influenza virus aerosols can travel beyond 1 meter, exceeding current safe distances for infection control.
- Further research is required to understand the infectivity of aerosolized influenza virus particles.
