[Science] Can viruses spread through aerosols?

This article is original by Translational Medicine Network.
Please indicate the source for reprinting.
Author: Tiffany Guide: In recent years of the new crown epidemic, scientists have carried out a number of studies on the new crown virus.
In a recent study, they not only discovered the new crown One of the main ways of spreading the virus, it has also been discovered that most other respiratory viruses are spreading in this same way.
.
.
As we all know, SARS-CoV-2 (New Coronavirus) is now raging around the world.
Caused, this virus mainly relies on inhalation of virus-carrying aerosols to spread.
In this way, the virus can easily spread in short or long distances
.

On this basis, scientists have studied the transmission methods and characteristics of some other viruses.
They found through experiments that not only the new coronavirus is the case, but other respiratory viruses are also transmitted in this way
.

For example, SARS virus, MERS coronavirus, influenza virus, measles virus, and rhinovirus that causes the common cold can all be transmitted through the above methods, and this aerosol can even accumulate in the indoor air and can last for many hours
.

The results of this research were published in an article titled "Airborne transmission of respiratory viruses" in "Science" magazine: This research was carried out by an international interdisciplinary research team, and they had a completely new way of spreading viruses.
Recognize
.

In the last century and at the beginning of the new crown pandemic, it is generally believed that respiratory viruses like the new crown virus are mainly transmitted through these two methods: the droplets produced when the infected person coughs and sneezes are transmitted to other people, Infect the virus by touching a surface contaminated with the virus
.

However, neither droplet transmission nor pollutant transmission seems to have been fully verified; however, among the many super-spreading incidents observed, infections occurred indoors more often than outdoors
.

A group of research teams from Taiwan, the United States, and Israel are eager to understand the spread of the new crown virus and other respiratory viruses.
Therefore, they reviewed and analyzed many super-transmission events during the spread of the new crown epidemic, and they finally discovered The same conclusion was reached: transmission through the air is the most likely way of transmission of the new coronavirus, rather than the way previously thought to be transmitted by contact with pollutant surfaces or droplets
.

Many of these unfortunate infections are caused by exposure to a virus-contaminated environment for an hour or more, poor ventilation in the house, not wearing a mask to protect against the virus, or not wearing a mask properly
.

The researchers also analyzed data collected from many other types of research-air sampling, polymerase chain reaction (PCR)-based research and cell culture research, epidemiological analysis, laboratory and clinical research and modeling research, In the end, they concluded that the airborne transmission of these new coronaviruses is the main route, and even most other respiratory viruses are mainly transmitted through the air
.

Airborne transmission is not limited to the new coronavirus
.

For a long time, people have not fully realized that viruses can also be spread by inhaling virus-carrying aerosols
.

Wang Jiachang, director of the Aerosol Science Research Center at National Sun Yat-sen University in Taiwan and an aerosol physical chemist, took the lead in expressing this conclusion.
He said: "It is time to change the traditional virus protection model by implementing aerosol preventive measures, which can be more effective.
Protect the public from the effects of the virus through this route of transmission
.

” The research team pointed out that the epidemic pattern of the spread of respiratory diseases can be traced back to a century ago
.

At the beginning of the 20th century, Charles Chapin, a famous public health figure, dismissed airborne transmission.
He was worried that people would be scared to take no action when talking about airborne transmission, and would replace hygiene habits
.

An unproven hypothesis mistakenly equates close-range infection with droplet transmission, forming the current paradigm for controlling the spread of respiratory viruses
.

However, Kim Prather said: "This assumption ignores the fact that aerosol transmission also occurs at short distances, because the closer a person is to an infected person who releases the aerosol, the higher the aerosol concentration he exhales
.

"Kim Prather is the director of the National Science Foundation Center for the Effects of Aerosols on Environmental Chemistry at the Scripps Institute of Oceanography at the University of California, San Diego, and the aerosol chemist who led the research
.

Breathing aerosols are formed by exhalation activities, such as breathing, talking, singing, shouting, coughing and sneezing
.

Before the outbreak of the new crown in 2019, the traditional size boundary between smoke-like aerosols and droplets was set to 5μm, and 100μm is a more suitable size boundary
.

The updated size better represents the largest particles that can be suspended in still air for more than 5 seconds (from a height of 1.
5 meters) and more than 1 meter away from the infected person and be inhaled
.

Josué Sznitman, a pulmonary physiologist at Technion in Israel, explained: “Their size mainly determines how long they can be suspended in the air, how far they can fly, whether they can be inhaled, and how deep they can enter the respiratory tract after being inhaled
.

Respiratory activity Most of the aerosols produced are smaller than 5 μm, which allows them to penetrate deep into the bronchioles and alveolar areas and deposit there
.

Studies have found that the virus is more abundant in aerosols smaller than 5 μm
.

"Another characteristic of aerosols that deserves serious consideration is their ability to be affected by airflow and ventilation
.

Ensuring adequate ventilation rates, filtration, and avoiding recirculation can help reduce the airborne transmission of aerosols carrying infectious viruses
.

University of Colorado Bo Jose-Luis Jimenez, an atmospheric aerosol chemist at the University of Texas, added: “The use of portable meters to monitor carbon dioxide helps to verify adequate ventilation.
The use of portable high-efficiency particulate air purifiers and upper room ultraviolet disinfection systems can also help reduce virus-carrying Aerosol concentration
.

"On the other hand, Linsey Marr of Virginia Tech said: "Plexiglas barriers that are commonly used to block droplets from indoor coughs and sneezes may "obstruct proper ventilation, exposing some people to higher air
.

" Marr has been studying the airborne transmission of pathogens for many years.
He found that it is better to use a mask to defend against viruses, and its protective ability is still stronger, because the mask helps to remove aerosols, and the barrier just transfers them.
This is An essential difference
.

"With the surge in infections caused by the delta variant and the increase in "new crown breakthrough cases" (infections in people who have been fully vaccinated), many governments and national disease control agencies have resumed the strategy of generally wearing masks in public.
Using a mask to protect yourself from viral infections is an effective way to stop virus-carrying aerosols from invading the human body
.

However, Seema S.
Lakdawala, a virologist at the University of Pittsburgh, added: “We need to consider a variety of methods to block the virus.
The spread of the virus, such as: vaccination, wearing a mask and regular ventilation can effectively block the further spread of the virus
.

If only a single strategy is not likely to play a strong role, these multiple methods are sufficient to block the further spread of the newly emerging mutant new coronavirus
.

"As more and more cases of new crown infections are caused by the spread of the virus through the air, this approach and theory of air transmission has become particularly convincing, and various research institutions have already noticed the spread of new crowns.
This feature
.

In April and May 2021, WHO and the U.
S.
Centers for Disease Control and Prevention recognized that inhaling virus-carrying aerosols is the main route for the new coronavirus to spread in short and long distances
.

This means that, In order to slow down the wanton spread of the new crown virus, all parts of the world should consider implementing preventive measures on aerosols, including: encouraging residents to wear masks generally, paying attention to wearing masks with high protective effects, increasing the ventilation rate of indoor spaces, and avoiding contamination indoor air recirculation, the air filter means mounted (installed HEPA filter, such an apparatus can effectively remove airborne particulates), an ultraviolet sterilizing lamp may be mounted like
.

this is a strong indication of a pandemic is the long-term The underestimated virus can spread through the air, and the need to protect people's right to breathe clean and pathogen-free air
.

The lessons we have learned from this pandemic will also help us adjust and change our treatment of possible outbreaks at any time The attitude towards the epidemic also points out the way for the people of the world in the post-epidemic era to face the epidemic
.

Aerosol preventive measures will not only help prevent the airborne transmission of respiratory diseases, but will also improve indoor air quality, which will give us health bring many benefits
.

references: https: //medicalxpress.
com/news/2021-08-sars-cov-respiratory-viruses-aerosols.
html Note: This article is intended to introduce the progress of medical research, treatment programs can not be used as a reference
.

as If you need health guidance, please go to a regular hospital for treatment
.

Popular·Article Organoids [Nature Sub-Journal] The use of stem cell-induced 3D brain organoids can accurately replicate human brain cancer early screening [Nature Sub-Journal] A new non-invasive early screening method for lung cancer based on blood cfDNA, with ultra-high detection rate! Organ [Science Sub-Journal] Subversion! It is the first time that a complete living tumor is 3D printed, and cancer exploration has entered the "real" 3D era.
Gene editing [Nature Sub-Journal] is a heavyweight! Academician Ye Yuru’s team used genome editing technology to treat Alzheimer’s disease and achieved a major breakthrough in early cancer screening [The Lancet] Subverted traditional detection methods and achieved a new breakthrough in early prostate cancer screening.
According to the experimental data of Vitamin C, it is found that the 2 times the dose recommended by the WHO should be used.
Industry dynamics [News] Oxford Nanopore's revenue in 2020 will increase by 119%, and the core business will continue to grow strongly.
New crown virus [The Lancet] Hospital has become a "point of infection"? Over one-tenth of people in the UK are infected with the gut microbiota of the new coronary pneumonia in the hospital [Science] How does obesity affect gut health? A new study takes you to reveal the answer! Early cancer screening [Science blockbuster] A major breakthrough in early screening for esophageal cancer! New crown virus [heavy weight] How terrible are the sequelae of the new crown virus? A large-scale survey of more than 80,000 people shows that after the new crown patients recover, there will be sequelae of cognitive decline! Human Metabolism [Science]: What are the key recommendations for human metabolism milestones from 8 days old to 95 years of age? Active Tumor Early Screening Innovative Technology Development Seminar The 3rd Shanghai International Cancer Conference The 5th Modern Clinical Molecular Diagnosis Symposium