Schools are facing a challenging situation as viral illnesses are on the rise, especially in classrooms. A recent study has shed light on the effectiveness of high-efficiency particulate air (HEPA) purifiers in reducing exposure to respiratory viruses in classroom settings.
The study, published in JAMA Network Open, conducted a secondary analysis of a randomized clinical trial led by researchers from Mass General Brigham. The findings revealed that even with HEPA purifiers in classrooms, exposure to respiratory viruses remained high. On average, air samples from classrooms contained three different respiratory viruses, with some classrooms harboring up to 13 viruses, including pathogens like respiratory syncytial virus (RSV) and influenza virus.
Dr. Peggy S. Lai, the corresponding author of the study, emphasized that the presence of HEPA purifiers did not lead to an overall reduction in viral load in classrooms. This suggests that additional interventions may be necessary to effectively mitigate the spread of respiratory viruses in school environments.
HEPA filters are designed to capture fine particulate matter from the air, but their real-world effectiveness in filtering respiratory viruses transmitted through aerosols and droplets has been limited. The researchers analyzed data from the School Inner-City Asthma Intervention Study (SICAS-2), which initially aimed to assess the impact of HEPA purifiers on asthma symptoms in elementary school students.
The study found that while HEPA purifiers did not decrease overall respiratory viral exposure in classrooms, there was a modest reduction in viral diversity by 32.8%. However, this decrease in viral diversity did not correlate with a decrease in school absences. The researchers did observe a relationship between lower humidity levels and higher viral exposure, suggesting that maintaining optimal humidity levels could be crucial in reducing viral transmission.
Dr. Lai emphasized the importance of addressing the risks posed by respiratory viruses to school-aged children and teachers. In addition to air filtration and ventilation improvements, maintaining classroom humidity between 40% and 60% could help lower viral exposures and enhance the comfort of students and teachers.
The study highlights the complexity of reducing viral exposure in classroom settings and underscores the need for multifaceted approaches to mitigate the spread of respiratory viruses. By combining air filtration strategies with humidity control measures, schools can create safer environments for students and staff.
For more information, you can access the study titled “Air Purifier Intervention for Respiratory Viral Exposure in Elementary Schools: A Secondary Analysis of a Randomized Clinical Trial” in JAMA Network Open. This research was conducted by Brigham and Women’s Hospital, aiming to provide valuable insights into improving indoor air quality and reducing viral transmission in school settings.
