Indoor Air Changes and Potential Implications for SARS-CoV-2 Transmission - JAMA Insights

As COVID-19 cases surge across the U.S. and Canada, this study is a reminder of the connection between ACH (Air changes per hour) and COVID-19 outbreaks.

Buildings have been associated with spread of infectious diseases, such as outbreaks of measles, influenza, and Legionella. With SARS-CoV-2, the majority of outbreaks involving 3 or more people have been linked with time spent indoors, and evidence confirms that far-field airborne transmission (defined as within-room but beyond 6 feet) of SARS-CoV-2 is occurring.

Conclusion

“Increasing air changes per hour and air filtration is a simplified but important concept that could be deployed to help reduce risk from within-room, far-field airborne transmission of SARS-CoV-2 and other respiratory infectious diseases. Healthy building controls like higher ventilation and enhanced filtration are a fundamental, but often overlooked, part of risk reduction strategies that could have benefit beyond the current pandemic.”

A replicable strategy for mapping air pollution’s community-level health impacts and catalyzing prevention - Boston Collage Research

Air pollution was responsible for an estimated 6.7 million deaths globally in 2019 and 197,000 deaths in the United States. Fossil fuel combustion is the major source.

Boston College researchers published a study underlying how air pollution is responsible for an estimated 2,780 deaths a year in Massachusetts, and for measurable cognitive loss in children exposed to fine particulate pollutants in the air they breathe.

Hypothesis

Mapping air pollution’s health impacts at the community level using publicly available data and open-source software will provide a replicable strategy for catalyzing pollution prevention.

Methods

Using EPA’s Environmental Benefits Mapping and Analysis (BenMAP-CE) software and state data, we quantified the effects of airborne fine particulate matter (PM2.5) pollution on disease, death and children’s cognitive function (IQ Loss) in each city and town in Massachusetts. To develop a first-order estimate of PM2.5 pollution’s impact on child IQ, we derived a concentration-response coefficient through literature review.

Findings

The annual mean PM2.5 concentration in Massachusetts in 2019 was 6.3 μg/M3, a level below EPA’s standard of 12 μg/M3 and above WHO’s guideline of 5 μg/M3. In adults, PM2.5 pollution was responsible for an estimated 2780 (Confidence Interval [CI] 2726 – 2853) deaths: 1677 (CI, 1346 – 1926) from cardiovascular disease, 2185 (CI, 941–3409) from lung cancer, 200 (CI, 66–316) from stroke, and 343 (CI, 222–458) from chronic respiratory disease. In children, PM2.5 pollution was responsible for 308 (CI, 105–471) low-weight births, 15,386 (CJ, 5433-23,483) asthma cases, and a provisionally estimated loss of nearly 2 million Performance IQ points; IQ loss impairs children’s school performance, reduces graduation rates and decreases lifetime earnings. Air-pollution-related disease, death and IQ loss were most severe in low-income, minority communities, but occurred in every city and town in Massachusetts regardless of location, demographics or median family income.

Conclusion

Disease, death and IQ loss occur at air pollution exposure levels below current EPA standards. Prevention of disease and premature death and preservation of children’s cognitive function will require that EPA air quality standards be tightened. Enduring prevention will require government-incentivized transition to renewable energy coupled with phase-outs of subsidies and tax breaks for fossil fuels. Highly localized information on air pollution’s impacts on health and on children’s cognitive function has potential to catalyze pollution prevention.

CELEBRITY INVOLVEMENT: ELON MUSK TO JOIN IAQ REVOLUTION

The world’s richest man says a system to improve indoor air quality (IAQ) in homes is “on the future product list” for his electric vehicle manufacturer Tesla.

When it comes to making the latest indoor air quality technology available to consumers, Platinum Air Care has done so since 1999. The more technology and advancement in regards to indoor air quality, the better.

How Much Do Ventilation Systems Help Reduce COVID Transmission? - Verywellhealth.com

Key Takeaways

• Proper air flow can help reduce COVID-19 transmission indoors, even as mask mandates fall away.

• Air filters can protect again all three types of COVID transmission: inhalation, deposition, and touching.

• Research shows adding portable air purifiers to spaces that already have HVAC systems can significantly enhance air circulation.

By Jennifer Chesak

Published on May 16, 2022

Fact checked by Nick Blackmer

Herb Schmitz / Getty Images

Mask mandates are gradually disappearing. That leaves many people wondering about whether improved ventilation strategies in indoor public spaces help reduce transmission of COVID-19.

Experts say yes. Improved ventilation helps and is crucial going forward, especially as fewer people are wearing masks.

“It’s not an airtight guarantee that you’re not going to get COVID,” Andrew Noymer, PhD, MSc, epidemiologist and associate professor of population health and disease prevention at the University of California Irvine, told Verywell. “It’s just a much-reduced probability because the air isn’t as stale.”

Why Good Ventilation Is Crucial

Last month, a federal judge struck down the Centers for Disease Control and Prevention (CDC) mask mandate for planes, trains, and busses. Some carriers still have their own mandates and some cities still have mask rules that are also in effect for local public transit. But a large swath of the nation is now mandate free.

Experts say research shows enhanced indoor ventilation via filters and portable air purifiers can help reduce virus transmission in indoor public spaces. Plus, people can take steps to improve and monitor ventilation in private spaces as well, especially when planning to host guests.1

The virus that causes COVID-19 is spread in three ways: inhalation, deposition, and touching, according to the CDC. The virus is released in tiny droplets or aerosols when an infected person exhales, speaks, coughs, or sneezes. Transmission primarily occurs when someone else inhales the infected aerosols.

Infected aerosols can also be deposited from the air directly onto mucous membranes, such as the eyes, nose, or mouth. And aerosols can also contaminate surfaces that we touch. While surface transmission is unlikely, it is possible that we could become infected if we transfer the virus to a mucous membrane.2

“When you’re in an indoor, climate-controlled building, those little droplets can just waft around on air currents for minutes on end,” Noymer said.

If air is circulated through a ventilation system’s filter many times per hour, however, that can help reduce transmission. That’s because a good filter will trap aerosols, preventing them from recirculating. But all ventilation strategies, systems, and filters aren’t created equal.

The Environmental Protection Agency (EPA) recommends that building operators upgrade their filters to the highest efficiency that’s compatible with the building’s HVAC system and use portable air cleaners to enhance overall circulation to reduce viral transmission.3

Portable Air Purifiers Enhance Ventilation

In a recent study, researchers from the Well Living Lab, a collaboration between the Mayo Clinic and Delos, simulated a classroom environment. They strategically placed three recirculating portable air filtration units around the room, which also had HVAC.

The researchers then used dye-tagged particles and a breathing simulator to test how the aerosols dispersed and deposited. They tested conditions with just the HVAC unit running and with the HVAC running in tandem with the portable units.1

“What we found is that the use of those portable air purification units really allowed for a reduction of up to five times lower particle concentration,” Zachary Pope, PhD, MS, a research scientist and study author, told Verywell. “So obviously having that reduction in the amount of particles in the air is good because you theoretically do not have as many potentially infectious particles in the air.”

In their simulation, the researchers also placed items commonly used in a classroom, like desks, a whiteboard, digital tablets, and more—all surfaces that can potentially become contaminated.1

“Our study was able to help show that portable air purification—because it reduces the amount of particles in the air—also reduces the amount of particles that deposit on the surfaces,” Pope said. “And those two factors really help us limit both direct inhalation transmission as well as transmission via different surfaces in a room.”

Although the study tested a mock classroom, Pope says portable air purifiers are useful for other settings, like offices, cubicles, homes, and more. “They’re very cost effective and they’re very impactful,” he said.

The use of portable air purifiers is especially important in buildings where ventilation systems cannot be upgraded. And even when HVAC systems can be improved, portable units further enhance air circulation and help clean the air.1

Buying a Portable Air Purifier

If you’re buying a portable air purifier, Pope recommends first knowing the dimensions of your space. Then, check the specifications for the air purifier’s cubic feet per minute (CFM) rating.

“Ideally what you want to have is for that CFM value to be at least two-thirds of the square footage of your room,” he said. For example, a unit with a 100 CFM rating can adequately ventilate 150 square feet. If you have a larger room, you may need two or more units.

If you need an even more budget-friendly option, Noymer says there’s what he calls a “hack” if you make a Corsi-Rosenthal Box. The method involves using a box fan and HVAC filters.

“It’s basically a DIY,” he said.

A study from researchers at the University of California Davis shows that the Corsi-Rosenthal Box reduces particle concentration. The study is available as a preprint and has not yet been peer-reviewed.4

The university offers instructions for making a Corsi-Rosenthal Box on its website.

Intense exercise leads to ‘super emission’ of particles that can spread COVID-19 - Today.com

A person’s aerosol particle emission increased 132-fold on average when he or she worked out at the highest intensity, a small study found.

“Vigorous exercise puts out a lot of particles in the air and very small droplets that waft in the air," experts say.Getty Images/iStockphoto

June 13, 2022, 8:25 AM EDT / Source: TODAY

By A. Pawlowski

That gym member panting next to you in spin class may be exhaling a huge amount of aerosol particles — the kind that can transmit viruses, including the one that causes COVID-19 — leading to a “super emission” during intense exercise, a new study has found.

A person’s aerosol particle emission increased 132-fold on average when he or she worked out at the highest intensity — skyrocketing from about 580 particles per minute at rest to about 76,000 during maximum exertion.

That startling rise might partly explain “superspreader events” during high-intensity group exercise indoors, the authors wrote in Proceedings of the National Academy of Sciences.

In 2020, researchers in South Korea found 112 COVID-19 cases linked to fitness dance classes at 12 different gyms. That same year, Hawaii reported a “COVID-19 cluster” where 21 cases at three fitness facilities were linked to an instructor who taught a spin class and other group classes days before experiencing symptoms.

“Vigorous exercise puts out a lot of particles in the air and very small droplets that waft in the air, making it more likely that they’re going to linger around and you could pick it up,” Dr. Marissa Levine, director of the Center for Leadership in Public Health Practice at the University of South Florida in Tampa, told TODAY. She was not involved in the new study.

“It’s particularly worrisome as we see these waves of disease… if you have a variant that’s easy to transmit and you have a lot of them in a small space because people are exercising vigorously, that means your risk is going to be higher if you go into that setting.”

Public Schools Have Not Improved Indoor Air Quality Since Pandemic - CDC Report

CDC report finds fewer than 40% of schools have replaced or upgraded their HVAC systems

Read the full article here

“School facility managers and custodians are tasked with creating a healthy environment for students and teachers during the pandemic. Although schools have been concentrating on increased and enhanced cleaning, most have not given as much attention to the indoor air quality (IAQ), even though COVID-19 is spread through the air. According to a new report released by the U.S. Centers for Disease Control and Prevention (CDC), fewer than 40% of American public schools have replaced or upgraded their HVAC systems since the start of the pandemic and even less (28%) are using high-efficiency particulate air (HEPA) filters.”

“The report also found that 73.6% of public schools opted to relocate activities outdoors while 70.5% chose to use the same filtration systems as before. The CDC’s information revealed similar results as a report issued last month by the U.S. Green Building Council (USGBC) which found IAQ in schools lacking.”

“Funding appears to be a major obstacle for schools, as roughly 25% of school officials believe they do not have the resources to improve ventilation, while another quarter are “unsure” whether funding is available. The time-consuming process of hiring contractors and acquiring state/federal approval is also a likely hindrance.”