One of the persistent questions about the Novel Coronavirus 19 or COVID-19 remains is the virus airborne? Can the virus be transmitted and a person become infected simply by breathing the air around them? We know that heavy droplets spray during a sneeze or a heavy cough. Can the virus pass from one person to another in the aerosol mist expelled by breathing or speaking?
We are encouraged to cover a sneeze or cough with tissue, a handkerchief, or the bend in our elbow. Each of these measures reduces the amount of potentially infectious material that we spray into the air around us. What can stop the potential infection from the aerosol mist produced in speaking or breathing?
We know how difficult it is to keep any area clean that people frequent. Therefore, we are strongly encouraged to undertake measures to prevent and mitigate the potential for infectious transmissions, such as:
Frequently washing your hands with soap and warm water for a minimum of 20-30 seconds,
using hand sanitizer that is at least 60% alcohol.
Wearing face coverings especially N95 masks
Regularly cleaning and disinfecting high touch and high traffic areas of our homes, churches, businesses and other places we frequent,
Social-distancing by remaining a minimum of 6 feet away from other people.
Self-isolating by staying at home and limiting your movement outside your home to essential visits to the store, pharmacy or doctor and
Wearing a mask or face-covering when in public spaces
All of these actions may slow the spread of the virus and flatten the curve of infection. We do these things because we want to keep the healthcare system from being overwhelmed with the number of hospitalizations and lowering its ability to provide adequate care for the sickest patients.
Each of these measures, while not cures are wise to do. Here are some of the reasons:
People may be “Presymptomatic,” meaning they are infected but have not yet shown any symptoms. It is during this period when a person may be highly infectious.
You may be “Asymptomatic” meaning you have the infection but don’t show any symptoms or very mild symptoms that may be mistaken for allergies or a cold. If you are Asymptomatic, you are highly infectious and may unwittingly spread the virus to others who may not survive the infection.
The persistent question about the airborne transmission of Covid-19 continues to defy a definite answer. Let’s review the concern. The medical experts believe that the primary means of infection is through:
Heavy droplets from coughing or sneezing within 6 feet of another person.
Contact with the infected droplets that land on surfaces or that are transported on a person’s hand to surfaces.
The surfaces that can be infected include tables, chairs, light switches, doorknobs, computer mouses, etc., that are then touched and transported by your hands when you contact your face.
There is, however, the concern that the virus can transmit through breathing or speaking because of the “Aerosol” transmission. While “Aerosol” transmission of the virus remains in question, there is evidence that the microscopic droplets of moisture that passes from your lungs through the act of breathing or speaking may carry the virus.
Consider the fact that in cold weather below 32 degrees (f) or 0 degrees (c), your breath condenses into a visible vapor. The same microscopic mist expels in warmer temperatures as an invisible aerosol. You can test this fact by placing your hand in front of your mouth and speaking. You feel the bursts of vapor forced from your lungs, in other words, the aerosol spray.
The amount of virus that the “Aerosol” can contain may or may not be enough to infect another person. The jury remains out on that possibility. One recent study suggested that the “Aerosol” may contain enough infectious material to merit study.
“While the current SARS-CoV-2 specific research is limited, the results of available studies are consistent with aerosolization of virus from normal breathing,” wrote Harvey Fineberg, MD, PhD, chair of the National Academies Standing Committee on Emerging Infectious Diseases and 21st Century Health Threats, in a rapid expert consultation issued April 2. [1]
The sheer newness of Covid-19 makes definite conclusions difficult to draw about aerosol infection. A study conducted on Influenza A arrived at the following conclusion when comparing infection material from coughing versus breathing.
“Viable influenza A virus was detected more often in cough aerosol particles than in exhalation aerosol particles, but the difference was not large. Because individuals breathe much more often than they cough, these results suggest that breathing may generate more airborne infectious material than coughing over time. However, both respiratory activities could be important in airborne influenza transmission. Our results are also consistent with the theory that much of the aerosol containing viable influenza originates deep in the lungs.”[2]
According to a National Safety Council article entitled,
“Aerosol transmission of COVID-19 can exceed 6 feet, shoes can spread coronavirus on floors: study” data collected from Wuhan, China demonstrated evidence of aerosol transmission of Covid-19 up to13 feet away from patients. The article quotes the research stating,
“The researchers collected swab samples from potentially contaminated objects in an intensive care unit and a general ward at Huoshenshan Hospital in Wuhan from Feb. 19 to March 2. The objects included floors, computer mice, trash cans, bed handrails, patient masks and personal protective equipment; indoor air and air outlets also were sampled. The ICU contained 15 patients with severe COVID-19, while the general ward had 24 patients with “milder disease.”
SARS-CoV-2 was detected in the air as much as 13 feet from the patients – more than twice the 6 feet distance the Centers for Disease Control and Prevention recommends for adequate physical distancing. Further, medical staff tracked the virus on the floor, as indicated by a 100% positive rate in a pharmacy where no patients were allowed.
“We highly recommend that persons disinfect shoe soles before walking out of wards containing COVID-19 patients,” the researchers said, adding that the rate of positivity was also “relatively high” on objects frequently touched by medical staff, including computer mice, trash cans, bed handrails, and doorknobs.”
While the information cited above originated in intensive care units and general patient areas of a hospital, it is relevant for arenas where potentially infectious people may gather. The potential infectiousness of aerosol through breathing and speaking serves to heighten the stakes of resuming public gatherings, even with the best cleaning and disinfecting, face coverings, temperature screenings, and hand washing.
U.S. states plan to re-open the economy, and national leaders call for a return to business, as usual, but there remain far too many unanswered questions. The ultimate cost of resuming gatherings without the aid of universal testing may produce disastrous results for families, churches, businesses, communities, cities, states, and ultimately the nation.
Sources:
[1] https://www.webmd.com/lung/news/20200404/coronavirus-is-aerosolized-through-talking-exhalation-new-report-says#1 [2] https://pubmed.ncbi.nlm.nih.gov/26991074/
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