Viable SARS-CoV-2 Aerosols Detected in the Room of COVID-19 Patients

Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) transmission has long been associated with respiratory droplets when a person coughs, sneezes, or speaks. Recently, evidence has been shown that SARS-CoV-2 viral particles remain in the air as aerosols and can spread faster.

Now, a new study by researchers at the University of Florida highlights the role of SARS-CoV-2 aerosols in disease transmission.

Aerosol transmission

As the pandemic grows and spreads around the world, many scientists have suggested that airborne transmission is possible in the spread of SARS-CoV-2 in addition to respiratory droplets.

WHO recently stated that aerosol transmission has been identified, especially in poorly ventilated areas. Earlier, the WHO stated that aerosol release is possible only in hospitals through medical procedures involving aerosol release, including nebulization and inhalation.

“WHO is actively discussing with and evaluating with the scientific community whether SARS-CoV-2 could spread via aerosols, especially in poorly ventilated indoor environments, especially in the absence of aerosol generation procedures. WHO explained.

Aerosol transmission occurs when some respiratory droplets evaporate to produce microscopic aerosols of less than about 5 µm, and when a person breathes, coughs, sneezes, or speaks. People can inhale aerosols that can cause infections. Aerosols contain enough virus to cause an infection.

Survey published on Preprint Server medRxiv* Indicates that patients with respiratory symptoms of COVID-19 produce aerosols in the absence of viable aerosol generating procedures that include SARS-CoV-2. These aerosols contain viruses and can cause the transmission of disease-causing pathogens.

the study

To reach their findings, the team collected air samples in the room of two COVID-19 patients. Nasopharyngeal swab Positive for SARS-CoV-2. The researchers used a VIVAS air sampler and the samples were subjected to RT-qPCR and virus culture.

Schematic of the room showing the position of the patient’s bed and air sampler.

Testing revealed that viable virus was isolated from an air sample taken approximately 2 to 4.8 meters from the patient. The genomic sequence of the novel coronavirus strain isolated from the material collected by the air sample was identical to that isolated from swabs of patients with active infection.

“Patients with respiratory symptoms of COVID-19 produce aerosols in the absence of viable SARS-CoV-2 containing aerosolization procedures, and these aerosols may serve as sources of the virus.” The researchers wrote in the paper.

The findings revealed how the virus spreads indoors. The impact of research on public health is widespread, and current best practices, especially for controlling the spread of COVID-19, focus on face covering and mask wear, social distance, and frequent hand washing.

However, for airborne transmission, a physical distance of approximately 6 feet is not sufficient for indoor environments. Researchers are looking for clear guidance on control measures for SARS-CoV-2 aerosols. This will prevent the spread of the virus, especially indoors.

Cytopathic effect of Vero E6 cells inoculated with substances collected from air during air sampling 1-1. [A] Mock infected Vero E6 cells, 10 days post inoculation, sterile collection medium. [B].. Large cytoplasmic vacuoles of Vero E6 cells inoculated at 4 dpi with collection medium from BioSpot Sample 1-1. [C] Early focus of infection 7 dpi. [D] The focus of infection is 10 dpi. There are detached round cells, some of which are clumps. Adherent cells that remain at the focus of this infection have a dark cytoplasm, some have large cytoplasmic inclusions, and some cells are elongated. Original magnification at 400X.

What can you do

Understanding how, when, and under what conditions SARS-CoV-2 spreads is essential to developing effective public health and infection control measures to control the spread of the virus.

Many countries are currently implementing health measures such as maintaining social distances, wearing masks, washing hands regularly and avoiding the crowd due to the risk of COVID-19 infection. Respiratory droplets are known to be the main route of infection. Nevertheless, due to the emerging evidence of airborne transmission, health professionals recommend changing these health measures, especially in indoor spaces where ventilation is restricted.

Above all, wearing a mask in the office, at work or in groceries is very important to prevent the spread of the virus. In addition, ventilation needs to be improved, but some experts say that incorporating natural air can reduce the spread of the virus.

To date, there have been 18.73 million confirmed cases worldwide and more than 706,000 deaths. Thousands of cases are added daily, but a second wave of viruses has been reported in other countries. As lockdown protection is relaxed, it is important that people be more vigilant to prevent infections.

*Important Notices

medRxiv It publishes preliminary, non-peer reviewed scientific reports and should not be considered conclusive and should not guide clinical practice/health-related behaviors or be treated as established information.