Airborne Transmission / Can Coronavirus Spread Through Dust Particles In Air?

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trader32176
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Airborne Transmission / Can Coronavirus Spread Through Dust Particles In Air?

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Can Coronavirus Spread Through Dust Particles In Air?

https://conahec.org/news/can-coronaviru ... ossibility

Can the SARS-CoV-2, the virus that causes COVID-19, spread through dust particles? A recent study has raised this alarming possibility.

It has long been assumed that the airborne transmission of viruses, such as the one that causes COVID-19, occurs through the respiratory droplets emitted by infected person when they sneeze, cough or speak. But scientists have now demonstrated that airborne viruses can also move around via non-respiratory droplets, such as microscopic particles known as “aerosolized fomites.”

Researchers at the University of California, Davis, and the Icahn School of Medicine at Mt. Sinai showed that microscopic particles carrying the influenza virus can be generated from inanimate objects, through simple actions like rubbing a contaminated paper tissue. Their findings were published in Nature Communications.

The study did not involve the novel coronavirus. But the World Health Organization (WHO) just last month acknowledged the SARS-CoV-2 virus could be airborne, making the study's findings important in combating spread of the pandemic that has so far killed more than 780,000 people globally and infected 22.16 million.

"It’s really shocking to most virologists and epidemiologists that airborne dust, rather than expiratory droplets, can carry influenza virus capable of infecting animals. Transmission via dust opens up whole new areas of investigation and has profound implications for how we interpret laboratory experiments as well as epidemiological investigations of outbreaks," said the study’s lead researcher William Ristenpart of the UC Davis Department of Chemical Engineering.

Researchers previously believed that airborne viruses like the influenza virus spread by several different routes, such as respiratory droplets from an infected person or via secondary objects like used tissues or door handles. However, very little is known about which routes are more important.

Dried influenza virus can transmit the infection through air

The experts at UC Davis in collaboration with the virologists at Mount Sinai said they demonstrated that infected guinea pigs heavily contaminate their fur and surrounding environment with virus and that "if these dust particulates become contaminated with influenza virus they can serve as aerosolized fomites that carry the virus to a susceptible guinea pig through the air."

They then sought to analyze whether tiny nonrespiratory particles could carry the virus between guinea pigs. For this they used an automated particle sizer that counted airborne particles. Their observations on uninfected guinea pigs showed that the animals gave off spikes of up to 1,000 particles per second while they moved around their cage. Surprisingly, they found that the guinea pigs’ gave off the particles at a much lower rate during normal breathing.

They found that immune but contaminated guinea pigs carried the virus on their fur and transmitted it through the air to other vulnerable animals. The study demonstrated that the virus didn’t have to come directly from the respiratory tract to be infectious.

"We conclude that airborne particulate matter from a non-respiratory source is able to transmit influenza virus through the air to a susceptible host," the researchers said.

They also tested whether microscopic fibers from an inanimate object could carry infectious viral particles. After treating paper facial tissues with the virus, they dried them out and then crumpled them in front of the automated particle sizer. They found that crumpling the paper tissues released up to 900 particles per second in a size range that could be inhaled. Particles from the contaminated paper tissues were able to infect cells.

"Dried influenza virus remains viable in the environment, on materials like paper tissues and on the bodies of living animals, long enough to be aerosolized on non-respiratory dust particles that can transmit the infection through the air to new mammalian hosts," said the researchers in their paper published in Nature Communications.

To view article, please visit: https://apple.news/AhYqumKFpRxO37tmQHi3f1g
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Re: Airborne Transmission

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Is COVID-19 Airborne?

11/4/20


https://www.houstonmethodist.org/blog/a ... -airborne/

Since the first days of the pandemic, we've continued to learn more and more about COVID-19, including how it spreads and how to protect ourselves.

When it comes to spread, in particular, experts have hypothesized for many months that this new coronavirus may be airborne. But what does this mean? And — most importantly — does it change the preventive measures needed to keep you and your family safe from COVID-19?

To understand whether or not COVID-19 is really airborne, as well as what this means for our health and safety, we spoke to Dr. Tim Connolly, pulmonologist at Houston Methodist.

Q: What does airborne mean?

Dr. Connolly: We all know by now that viruses can be passed from person-to-person via handshakes or touching contaminated surfaces (and then touching your eyes, nose or mouth).

When it comes to viral spread through the air, however, it's a bit more complicated than you may think. There are two principle modes of air-based spread of viruses:

Respiratory droplets
Airborne transmission

Respiratory droplets are little balls of saliva and moisture, potentially containing virus such as COVID-19, released from your mouth and nose — flying forward into your immediate area when you speak, cough or sneeze. These droplets don't travel very far, however, and are generally caught by even a simple face mask. During the pandemic, the logic behind mask-wearing and social distancing of at least six feet is principally to control the spread of COVID-19 via respiratory droplets.

To be considered airborne, a virus must be able to remain in the air for a longer period usually by clinging to much smaller particles of water vapor or dust. If you've ever seen dust hanging in the air when walking into a sun-lit room, an airborne virus can hang glide on these dust particles in a room for up to three hours at a time. Viruses lingering in the air can gain entry into your body through your eyes, as well as your nose and mouth.

Q: How airborne is COVID-19?

Dr. Connolly: According to recent updates issued by the CDC, there's increasing evidence that COVID-19 is airborne in certain situations, particularly in enclosed, poorly ventilated spaces.

In addition to the simple acts of talking, coughing and sneezing, other common activities that can encourage the new coronavirus to become airborne include:

Vigorously exercising at the gym
Singing at a religious service
Cheering at a rally, sporting event or concert

The airborne nature of COVID-19 may help explain the dramatic spread of the infection through certain environments, including cruise ships, nursing homes and prisons. It also explains why 22% of the recent spike of cases in El Paso, Texas, have been traced back to "big-box" stores.

While visiting a store, if enough individuals who are carrying the virus fail to wear masks — even simple, cloth-based ones — any airborne viral particles generated can then linger in the enclosed indoor space. Over the next several hours, unsuspecting customers who pass through this cloud of virus may ultimately become sick.

In a medical setting, several procedures can also encourage the virus to become airborne, including: nebulizer breathing treatments for asthma or COPD, CPAP machines for sleep apnea, and any medical interventions involving a patient's airway, such as placement of a breathing tube for surgery, bronchoscopy or tracheostomy. Whenever medical practitioners are involved in aerosol-producing procedures, N95 masks and other complete personal protective equipment (PPE) are absolutely essential.

Q: What precautions can help prevent airborne spread of COVID-19?


Dr. Connolly: The simple preventive measures public health professionals have been emphasizing since the start of the pandemic are still far and away the most effective ways to prevent getting sick with COVID-19.

These safety practices include:

Social distancing of at least six feet whenever possible
Limiting exposure to (or extended duration within) any public indoor environments, such as bars, restaurants, religious buildings, gyms and grocery stores
Avoiding visiting with someone inside his or her home (spending a short amount of time with someone outdoors is generally safer)
Wearing a mask!

With the realization that the coronavirus can potentially linger in the air for hours and also infect via your eyes, it's best to cover as many portals of entry as possible especially when walking in public spaces. For instance, when my family and I go out in public to the pharmacy, a coffee shop or gas station restrooms on a road trip, we wear masks and simple clear glasses. Similarly, when my kids walk the hallways at their schools, they wear masks and protective eyewear.
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Re: Airborne Transmission

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Air quality could influence the virulence of COVID-19 disease

11/24/20


https://www.news-medical.net/news/20201 ... sease.aspx


The correlation between the high concentration of fine particles and the severity of influenza waves is well known to epidemiologists. An interdisciplinary team from the University of Geneva (UNIGE) and the ETH Zürich spin-off Meteodat investigated possible interactions between acutely elevated levels of fine particulate matter and the virulence of the coronavirus disease. Their results, published in the journal Earth Systems and Environment, suggest that high concentrations of particles less than 2.5 micrometers in size may modulate, or even amplify, the waves of SARS-CoV-2 contamination and explain in part the particular profile of the COVID-19 pandemic.

The increase in fine particles is generally favored by air temperature inversions, characterized by fog situations, or by Saharan dust intrusions. The study provides preventive measures related to air pollution to limit future outbreaks of morbidity and mortality due to the coronavirus.

Epidemiologists widely agree that there is a correlation between acute and locally elevated concentrations of fine particles and the severity of influenza waves. "We have investigated whether such a link also exists with the virulence of COVID-19 disease," says Mario Rohrer, researcher at the Institute for Environmental Sciences of the Faculty of Sciences of UNIGE and director of Meteodat.

A surprising time lag

COVID-19 studies conducted in Italy and France suggest that SARS-CoV-2 was already present in Europe at the end of 2019, while the sharp increase in morbidity and mortality was only recorded in spring 2020 in Paris and London.

This time lag is surprising, but also suggests that something else than just the mere interaction of people may promote the transmission of the virus, and particularly the severity of the infection."

Mario Rohrer, researcher at the Institute for Environmental Sciences of the Faculty of Sciences of UNIGE and director of Meteodat

His research team has been able to show that these increases in cases followed phases where the levels of fine particles in the air were higher.

The team made similar observations in the Swiss canton of Ticino, where fine-particle pollution increased sharply during a period of shallow fog on the Magadino plain and the Sotto Ceneri, observed at the end of February 2020. "Shortly afterwards, an explosive increase in hospital admissions due to COVID-19 was recorded in Ticino. The fact that a large carnival event with some 150,000 visitors took place at the same time probably had an additional impact on the spread of the virus," says Mario Rohrer.

The information is important for Switzerland because the increase in fine particle concentrations is particularly frequent during thermal inversions, i.e. when fog forms on the Swiss Plateau, thus limiting the exchange of air masses. In these situations, emissions accumulate in the layer of air underneath the fog. Switzerland is also frequently swept by dust from Saharan sandstorms, also pointed out in this study.

Aggravating factor

The Swiss research team shows that acute concentrations of fine particles, especially those smaller than 2.5 micrometers, cause inflammation of the respiratory, pulmonary and cardiovascular tracts and thicken the blood. "In combination with a viral infection, these inflammatory factors can lead to a serious progression of the disease. Inflammation also promotes the attachment of the virus to cells," he says. In addition, the coronavirus may also be transported by the fine particles. "This has already been demonstrated for influenza and an Italian study found coronavirus RNA on fine particles. All this remains to be demonstrated, of course, but it is a likely possibility," adds Rohrer.

A multifactorial pandemic


Nonetheless, the researchers also emphasize that, although particulate matter pollution can influence the virulence of the virus and possible severe disease progression, physiological, social or economic factors will clearly also influence the further course of the pandemic. Mario Rohrer concludes that the findings of this study offer the possibility of taking preventive measures in the event of future increases in fine particulate matter concentrations, thus limiting a new flare-up of Covid-19 morbidity and mortality.
trader32176
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Re: Airborne Transmission

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For Scientists Who Study Virus Transmission, 2020 Was A Watershed Year

12/26/20


https://www.npr.org/sections/health-sho ... rshed-year


When Linsey Marr looks back at the beginning of 2020, what strikes her is how few people in the world really understood how viruses can travel through the air.

"In the past year, we've come farther in understanding airborne transmission, or at least kind of beyond just the few experts who study it, than we have in decades," says Marr. "Frankly, I thought it would take us another 30 years to get to where we are now."

The urgency of the coronavirus pandemic thrust her once-obscure field into the spotlight, as everyone from public health experts to ordinary citizens tried to gauge the safety of myriad activities like going to the grocery store, swimming at the beach, or gathering for a party.

"Back in January, the understanding of how viruses spread through the air was really primitive and incorrect," says Marr, a researcher at Virginia Tech who has spent years studying virus transmission. "It's been pretty wild to see airborne transmission of viruses become big news."

At the start of this coronavirus outbreak, the prevailing assumption among many medical experts was that respiratory viruses primarily spread through droplets of saliva and mucus that fly into the air after a cough or a sneeze. These were thought to travel only a short distance before falling to a surface. Public health messages consequently urged people to wash their hands and avoid touching their faces.

The coronavirus wasn't thought to be "airborne," a word associated with viruses like the one that causes measles. An airborne virus was widely considered to be a germ that could travel in tiny particles called aerosols that hang suspended in the air and linger for quite a while, potentially traveling long distances.

But, in reality, there's no clear cutoff between a virus that travels in aerosols and one that travels in larger droplets, says Marr. Infected people can give off respiratory viruses in particles of all different sizes that can travel a variety of distances, and big droplets can evaporate away into smaller ones. Very close to an infected person, the concentration of airborne virus could be high and others could simply inhale it.

As the new coronavirus began to spread, it sure seemed like airborne spread—at short range—might be critical.

"Once it became more apparent that this was a really important route of transmission, you know, I and others started making noise about this," says Marr, who sent out a Tweet in early March that said "Let's talk about airborne transmission of SARSCOV2 and other viruses. A discussion is needed to improve accuracy and reduce fear associated with the term."

Meanwhile, scientific research on how the COVID-19 virus moved through the air was being done at an astonishingly rapid pace.

"We're not even 12 months in, and we know things about this virus that we don't know about viruses that have been around for decades," says Josh Santarpia, a researcher at the University of Nebraska Medical Center.

He notes that no one has been able to grow measles virus from an air sample, and yet some people insisted that this kind of proof was needed before saying that the novel coronavirus could be airborne.

"It was interesting that the burden of proof was so high for this virus when it wasn't for these other things that we just sort of generally consider to be airborne," says Santarpia.

His medical center took care of some of the first people with coronavirus in the United States, and Santarpia recalls standing at the end of their beds with a device that collected air while they talked or breathed. His lab then analyzed the tiny airborne droplets, looking for the genetic signature of the coronavirus.

"We were getting positives, more than one positive in the air samples," says Santarpia. "I was shocked." Signs of the virus were in such tiny particles, he worried it that nothing less than the most protective masks could stop it.

Soon, though, studies showed that even simple masks were able to reduce the amount of virus that gets out into the air, cutting the risk of transmission. Suddenly mask-wearing became an ordinary—if politically contentious--part of everyday life.

Santarpia was floored at how quickly ventilation became a normal subject of conversation for the public.

"You know, 'How well ventilated is this space? Should I spending time inside or outside?' " says Santarpia. "It's changed so much about the way we view the world."

Whether or not this will be a lasting change is an open question.

Donald Milton, a researcher at the University of Maryland, has spent a quarter-century thinking about the transmission of respiratory viruses through the air, and has published studies showing that better ventilation in offices and dormitories is associated with a lower risk of virus transmission.

He's hoping the experience this past year will lead to better engineering solutions being put in place to improve the overall safety of houses and other indoor spaces: things like enhanced ventilation, air filters, or using special lights up by a room's ceiling to disinfect the circulating air.

"How can we make indoor spaces safe so that we can keep our economy running and fight a pandemic without all the damage that we are seeing from the interventions that we have been forced to take this year?" says Milton. "I want to see us understand how it is that you can make a restaurant a safe place to be during a flu season and during a pandemic."

He thinks it's doable, but he worries that once vaccines get the coronavirus in check, people will just lose interest—until the next time there's a new virus that can be transmitted through the air.
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Re: Airborne Transmission / Can Coronavirus Spread Through Dust Particles In Air?

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Airborne viruses can spread on dust, non-respiratory particles

August 18, 2020

https://www.sciencedaily.com/releases/2 ... 094026.htm


Influenza viruses can spread through the air on dust, fibers and other microscopic particles, according to new research from the University of California, Davis and the Icahn School of Medicine at Mt. Sinai. The findings, with obvious implications for coronavirus transmission as well as influenza, are published Aug. 18 in Nature Communications.

"It's really shocking to most virologists and epidemiologists that airborne dust, rather than expiratory droplets, can carry influenza virus capable of infecting animals," said Professor William Ristenpart of the UC Davis Department of Chemical Engineering, who helped lead the research. "The implicit assumption is always that airborne transmission occurs because of respiratory droplets emitted by coughing, sneezing, or talking. Transmission via dust opens up whole new areas of investigation and has profound implications for how we interpret laboratory experiments as well as epidemiological investigations of outbreaks."

Fomites and influenza virus

Influenza virus is thought to spread by several different routes, including in droplets exhaled from the respiratory tract or on secondary objects such as door handles or used tissues. These secondary objects are called fomites. Yet little is known about which routes are the most important. The answer may be different for different strains of influenza virus or for other respiratory viruses, including coronaviruses such as SARS-CoV2.

In the new study, UC Davis engineering graduate student Sima Asadi and Ristenpart teamed up with virologists led by Dr. Nicole Bouvier at Mt. Sinai to look at whether tiny, non-respiratory particles they call "aerosolized fomites" could carry influenza virus between guinea pigs.

Using an automated particle sizer to count airborne particles, they found that uninfected guinea pigs give off spikes of up to 1,000 particles per second as they move around the cage. Particles given off by the animals' breathing were at a constant, much lower rate.

Immune guinea pigs with influenza virus painted on their fur could transmit the virus through the air to other, susceptible guinea pigs, showing that the virus did not have to come directly from the respiratory tract to be infectious.

Finally, the researchers tested whether microscopic fibers from an inanimate object could carry infectious viruses. They treated paper facial tissues with influenza virus, let them dry out, then crumpled them in front of the automated particle sizer. Crumpling the tissues released up to 900 particles per second in a size range that could be inhaled, they found. They were also able to infect cells from these particles released from the virus-contaminated paper tissues.

The work was supported by a grant from the National Institute of Allergy and Infectious Diseases of the National Institutes of Health.
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Re: Airborne Transmission / Can Coronavirus Spread Through Dust Particles In Air?

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Atmospheric particulate matter may influence the transmission and evolution of SARS-CoV-2

1/12/21


https://www.news-medical.net/news/20210 ... CoV-2.aspx


A recent study conducted at the University of Malta Medical School, Malta, has revealed that a drop in the level of particulate matter 2.5 (PM2.5), which are airborne pollutant particles with a diameter of 2.5 micrometers, in the atmosphere due to lockdown is associated with the arrival of a newer variant of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which has eventually displaced the original virus after lockdown. The new viral variant (D614G mutant) may be able to use other types of PM, including the one that originated from tobacco smoking, as a viral vector for transmission.

The study is currently available on the medRxiv* preprint server.

Background


As the COVID-19 pandemic continues exponentially, a second wave of SARS-CoV-2 infection has been observed in many countries globally. This could be due to the relaxation made by government bodies on control measures during the later phases of the pandemic. In addition to an increase in COVID-19 incidence, a rise in pollution level has also been observed during the post-lockdown phase. In this context, several environmental studies have shown the SARS-CoV-2 uses PM2.5 as a viral vector for transmission and that an increase in atmospheric PM2.5 level is associated with an induction in new COVID-19 cases in many cities in China. Moreover, there is evidence suggesting that PM2.5 may disrupt the pulmonary microbial defense system, which in turn may facilitate SARS-CoV-2 to invade and infect the respiratory system.

Current study design

The current study has been conducted to investigate whether an alteration in atmospheric PM2.5 level can influence the evolution of SARS-CoV-2 as well as its ability to infect host cells.

The scientists have used the Air Quality Index to obtain average PM2.5 levels in selective cities including Beijing, Sheffield, Nottingham, Sydney and Cambridge. In addition, they collected information about daily viral counts of the original and newer SARS-CoV-2 variants from the available literature.

Important observations

The study findings reveal that a concomitant increase in viral counts occurs with the rise in the atmospheric level of PM2.5 in the majority of cities, except Beijing. In these cities, a low baseline PM2.5 level has been observed before the rise in viral counts. This indicates that PM2.5 may serve as a potent viral vector that facilitates the transmission of SARS-CoV-2.

A different pattern has been observed in Beijing, wherein a 36% reduction in PM2.5 level has been observed when the viral count is decreased.

In the cities studied, a significant reduction in PM2.5 level has been observed after one week of regional and national lockdown.

Importantly, the arrival of a newer viral variant (D614G) has been found to coincide with declining PM2.5 levels. In Beijing, a highly increased PM2.5 level mainly correlates with the original SARS-CoV-2 but not with the mutant variant. In contrast, a correlation between the viral mutant and PM2.5 level has been observed in Sydney and Cambridge. In Sheffield and Nottingham, both the original and mutant forms of SARS-CoV-2 correlate with the PM2.5 level.

Study significance

The study findings highlight the role of environmental pollution, including PM2.5 level in influencing the transmission of SARS-CoV-2. In addition, PM2.5 seems to play a role in manipulating viral evolution. The original viral variant was the predominant one when the PM2.5 level was highly elevated. In contrast, the mutant variant gradually displaced the original form and became predominant when the PM2.5 level was decreased.

Several genetic studies sequencing the genome of SARS-CoV-2 have indicated that more than 13,000 mutations have already occurred over a period of less than a year. Such fast-occurring genetic mutations suggest a possibility of environmental adaptation of the virus as a part of natural selection. Therefore, it is possible that a change in atmospheric PM2.5 level serves as a driving force for both viral transmission and evolution.

Based on the study findings, the scientists suggest that the mutant SARS-CoV-2 may be utilizing other sources of PM, such as tobacco smoke-derived PM, as a viral vector to support transmission.

*Important Notice

medRxiv publishes preliminary scientific reports that are not peer-reviewed and, therefore, should not be regarded as conclusive, guide clinical practice/health-related behavior, or treated as established information.

Journal reference:

MedRxiv preprint server. 2021. Baron YM. Atmospheric PM2.5 before and after Lockdown in relation to COVID-19 Evolution and daily Viral Counts: Could Viral Natural Selection have occurred due to changes in the Airborne Pollutant PM2.5 acting as a Vector for SARS-CoV-2?. doi: https://doi.org/10.1101/2021.01.10.21249548, https://www.medrxiv.org/content/10.1101 ... 21249548v1
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Re: Airborne Transmission / Can Coronavirus Spread Through Dust Particles In Air?

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What are the dynamics of SARS-CoV-2 transmission inside an aircraft cabin?

1/14/21


https://www.news-medical.net/news/20210 ... cabin.aspx


A team of US scientists has recently evaluated the risk of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection among passengers present inside an aircraft cabin. The findings suggest that the risk of airborne viral transmission is minimal during long-duration flights. The study is currently available on the medRxiv* preprint server.

Background

Since its emergence in December 2019, SARS-CoV-2, the causative pathogen of the coronavirus disease 2019 (COVID-19), has already infected more than 92.68 million people and claimed more than 1.98 million lives worldwide. To contain the spread of SARS-CoV-2, several control measures, such as regional or national lockdowns, movement or travel restrictions, and physical distancing, etc., have been implemented to some degree by government bodies of most countries. As a consequence, many countries have faced serious socioeconomic crises. During the later phases of the pandemic, relaxations on control measures have been made to support the economy and overcome the crisis.

After lifts in travel restrictions, airline services have been resumed between in many countries, which raises a question about the risk of viral transmission during travel. Because an airborne transmission of SARS-CoV-2 is possible, the risk of acquiring infection is expected to be higher in enclosed or poorly ventilated places. Thus, it is believed that passengers or airline staff present inside an aircraft cabin for a prolonged period of time might be at higher risk of SARS-CoV-2 infection.

Current study design


In this study, the scientists have tried to quantify the risk of SARS-CoV-2 infection among passengers traveling via two large aircraft (Boeing 767 and 777 airframes). They have used fluorescent and DNA-tagged microspheres to analyze the dispersion and deposition of aerosol particles released from a simulated SARS-CoV-2-infected passenger. Specifically, they have measured the level of aerosols within the breathing zone of fellow passengers who are seating in same row with the simulated infected passenger or in rows ahead or behind the source. They performed these measurements at different locations inside the aircraft, as well as by placing the simulated infected passenger at multiple locations.

Important observations

Boeing 777

By measuring the percentage of particle penetration into the breathing zones, the scientists observed that the maximum exposure occurs in a seat next to the simulated infected passenger. The level of exposure has been found to be lower in seats that are placed in front of the source, whereas seats placed behind the source have a higher exposure level.

With further analysis, they have observed that mixing of contaminants within a row occurs rapidly and that the flow of contaminants is directed toward the aft of the aircraft where the outflow valve is located. In first-class sections where gaps between seats are wide, the level of exposure is found to be lower than the economy section.

Boeing 767

According to the findings, the risk of exposure in Boeing 767 is lower than the Boeing 777. However, both aircraft share similar characteristics of risk exposure. The flow of contaminants toward the aircraft aft is less in Boeing 767. The flow of contaminants released from the aft seat is directed toward the aft, whereas a forward flow is observed for contaminants released from the front-mid seat.

By conducting similar experiments using a simulated infection source with or without masks, about 15% reduction in the particle count has been observed in experiments conducted with a mask.

Study significance

The study findings suggest that there could be a limited risk of exposure to SARS-CoV-2-containing aerosols inside an aircraft due to rapid mixing, dilution, and removal. A lower level of aerosol is observed in the aft section of the aircraft, which indicates a lower risk of exposure. However, it is important to consider that the study findings are based on the simulation of a single source of infection, and thus, the transmission dynamics may vary in conditions with multiple infected passengers. Moreover, the study focuses on aerosols and small particulate matter of 1-3 µm. The transmission dynamics of large respiratory droplets have not been included in the study.

*Important Notice

medRxiv publishes preliminary scientific reports that are not peer-reviewed and, therefore, should not be regarded as conclusive, guide clinical practice/health-related behavior, or treated as established information.

Journal reference:

MedRxiv preprint server. 2021. Kinahan SM. Aerosol tracer testing in the cabin of wide-bodied Boeing 767 and 777 aircraft to simulate exposure potential of infectious particulate such as SARS-CoV-2. doi: https://doi.org/10.1101/2021.01.11.21249626, https://www.medrxiv.org/content/10.1101 ... 21249626v1
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