Written by: Husna Sultana
Summary of ‘The Lancet’ study on why COVID-19 is a transmitted via airborne means.
As per the article published in ‘The Lancet’ on April 15,2021, the following summarizes 10 scientific reasons why COVID-19 is transmitted via airborne means.
- The link between ‘Long-range transmission’ and Super spreading events strongly suggests the dominance of aerosol transmission. Example: Choir concerts
- Long-range transmission was observed in quarantine hotels where the patients were living in adjacent rooms and had not spent any time in the same room.
Asymptomatic or pre-symptomatic transmissions of coronavirus by people who are not coughing or sneezing and just by speaking (speaking produces thousands of aerosol particles and few large droplets) have accounted for an estimated 33% to 59% of COVID-19 spread globally, which suggests aerosol transmission.
- Coronavirus spread is higher in indoors (with no ventilation) than outdoors suggesting the lingering of droplets in the air.
- Infections were documented in health care organizations, where there is a strict use of masks and PPE (Personal protective Equipment) designed to protect against large droplets but not aerosol transmissions.
- Viable SARS-CoV-2 was found in the air samples from hospital rooms occupied by COVID-19 patients and their cars.
- SARS-CoV-2 was found in air filters and building ducts of hospitals with COVID-19 patients.
- Studies have shown that infections were spread via an air duct from infected animals to uninfected animals who were caged separately.
- There is no study which has provided strong evidence against airborne SARS-CoV-2 transmission. Secondary infections are mainly caused in indoor-crowded settings with poor ventilation.
- There is limited evidence to support coronavirus transmissions through touching the surfaces of objects, clothes or large droplets. Surface transmission, although possible, is not thought to be a significant risk.
Why is it important to ‘sanitize the air’ more than ‘sanitizing the surfaces?
Over the course of the pandemic, scientific understanding of the virus has changed. Studies on the outbreak have pointed out that the major transmissions were occurring by infected people who were spewing large droplets or small particles called ‘aerosols’. There is very low evidence suggesting transmission through surfaces.
Centers for Disease Control and Prevention (CDC) clarified its guidance about surface transmission in its scientific study released on April 5,2021 , stating that ‘The principal mode by which people are infected with SARS-CoV-2 is through exposure to respiratory droplets carrying infectious virus. It is possible for people to be infected through contact with contaminated surfaces or objects (fomites), but the risk is generally considered to be low’.
Can HEPA Air Purifiers Capture the Coronavirus or SARS-CoV-2?
- Air filtration using HEPA filters have become a critical weapon in the fight against the spread of COVID-19. The HEPA filter can trap the virus on the surface of the filter and prevent it from escaping back into the airstream.
- The fibers in a HEPA filter are designed to trap particles as small as 0.01 micron in diameter — just a tiny fraction of the width of a human hair.
- In its advice on cleaning and disinfecting homes during the pandemic, the CDC recognizes as much: “When used properly, air purifiers can help reduce airborne contaminants, including viruses, in a home or confined space.”
- In studies conducted by McGill University, it was confirmed that the material used in Airpura's HEPA filters showed close to 100 % aerosol particle removal efficiency for nanoparticles (as small as 0.01nm)
UVC radiation is a known disinfectant for air, water, and nonporous surfaces. UVC radiation has effectively been used for decades to reduce the spread of bacteria and viruses, such as tuberculosis. For this reason, UVC lamps are often called "germicidal"
- UVC radiation has been shown to alter the DNA of the SARS-Cov-2 virus. The alteration leads to inactivation of the virus.
- UVC radiation is commonly used inside air ducts to disinfect the air. This is the safest way to employ UVC radiation because direct UVC exposure to human skin or eyes may cause injuries, and installation of UVC within an air duct is less likely to cause exposure to skin and eyes. Some UVC lamps generate ozone. Ozone inhalation can be irritating to the airway also adversely affects the lungs in many ways.
- The UV lamps used in Airpura are classified as ‘Non-Ozone generating lamps’.
Best HEPA Air purifier for removal of Bacteria/viruses/Sars-Covid-19:
Airpura UV600/UV614 or Airpura I600-UV or Airpura P600/P614
Airborne and aerosolized viruses, bacteria, mold, chemicals and particles go through powerful filtration for near complete removal. Airpura's patented UV air purifiers destroy the DNA of microorganisms, (without emitting ozone), viruses, influenza and gastro as well as black mold, effectively neutralizing them. Airpura's 18 lbs (found in UV600/P600) of custom blended activated carbon adsorbs chemicals, VOC's, gases, and odor. A medical grade True HEPA filter provides powerful particle reduction of 99.97% of particulate matter as small as 0.3 microns including PM2.5, pollen, dust, dander.
Read studies here https://www.airpura.com/pages/research-and-studies