Repurposed “surgical wards” could benefit from this discovery but experts think it could also lead to cleaner air standards that could limit infection transmission through aerosols. Addenbrooke’s Hospital and the University of Cambridge put in an air filtering system in COVID-19 wards and discovered that it almost eliminated airborne SARS-CoV-2.
Dr. Vilas Navapurkar a Consultant in Intensive Care Medicine at CUH who led the study said: “Reducing the airborne transmission of the coronavirus is extremely important for the safety of both patients and staff. Effective PPE has made a huge difference but anything we can do to reduce the risk further is important.”
In COVID Wards An Air Filter Greatly Reduces The Amount Of Airborne
Repurposed COVID-19 units at Addenbrooke’s Hospital were used for the study. Patients who needed basic oxygen treatment or no respiratory support were cared for in one part while those who needed intrusive respiratory assistance such as tracheostomies were cared for in the second area of the hospital.
“Because of the numbers of patients being admitted with COVID-19 hospitals have had to use wards not designed for managing respiratory infections. During an intensely busy time, we were able to pull together a team from across the hospital and University to test whether portable air filtration devices which are relatively inexpensive might remove airborne SARS-CoV-2 and make these wards safer.”
On each of the sample days in the surge ward before activation of the air filter researchers were able to detect SARS-CoV-2. The team was unable to discover SARS-CoV-2 on any of the five testing days after the air filter was turned on and running constantly. SARS-CoV-2 was detected on three of the five sample days after the equipment was shut down and the sampling was repeated.
Even though it appears like a simple solution, it has provided great benefits so far and it would be interesting to see how it can be used on large scale across several hospitals. If the air filters are able to restrict the transmission even by a small margin, it would be of great help to the health care service providers who are struggling hard to bring the situation under control.
Andrew Conway Morris the study’s first author remarked in an interview: “We were astonished at how effective the air filters were at removing SARS-CoV-2 from the wards. They could increase safety onwards even though this was a tiny trial especially in locations that are not prepared to handle highly contagious diseases like COVID-19.”
In the weeks when the machine was turned off the scientists identified only small amounts of SARS-CoV-2 in the air and on one sample day while the machine was on the virus was detected. Both the surge ward and the ICU were found to have much lower levels of bacterial fungal and various viral bioaerosols due to the use of air filters.
Professor Stephen Baker said: “Cleaner air will reduce the risk of airborne disease transmission but it’s unlikely to be the case that just installing an air filter will be enough to guarantee the air is clean enough. Every room and every situation will be different. A key part of our work has been developing a robust way of measuring air quality.”
Dr. Navapurkar added: “We’re all familiar with the idea of having standards for clean water and of hygiene standards for food. We need now to agree on standards for what is acceptable air quality and how we meet and monitor those standards.”
We stress the need of reducing airborne transmission in hospitals and other public facilities, which will further protect healthcare personnel, patients, and the general public from the spread of disease.
