Air PollutionAir QualityCoronavirusCOVID-19

Short-Term Air Pollution Exposure Linked to Longer COVID Hospital Stays, According to New Research

By August 18, 2023 August 21st, 2023 No Comments
8 minutes to read

A 2023 study published in the European Respiratory Journal has demonstrated a link between air pollution exposure and the length of hospital stays in cases of COVID-19. Continue reading to learn about the results of the recent study from air pollution experts. 

How is Air Quality Related to COVID-19? 

COVID-19 is an airborne pathogen, which means that it is spread through respiratory droplets and aerosols containing virus particles. These respiratory droplets are a form of particulate matter (small particles that remain suspended in the air), which is one of the two categories of air pollution. 

Researchers across the world have already discovered important links between air quality and COVID-19 infections. Earlier studies have shown that air pollution exposure is associated with an increased risk of contracting an illness when in contact with the SARS-CoV-2 virus; in other words, pollution increases the likelihood of actually getting sick with COVID-19 as opposed to an asymptomatic infection. Additionally, early studies of the disease in Europe showed that higher levels of air pollution may increase the pathogen’s ability to spread between hosts. 

Read More: Air Pollution and COVID-19 — Study Shows Exposure to Air Pollution Increases Risk of Getting Sick with  COVID-19 

Ambient Air Pollution Exposure Can Predict Hospitalization Outcomes for COVID-19 Patients 

The European Respiratory Journal study examined 328 patients hospitalized for COVID-19 in Belgium between May 2020 and March 2021. Researchers calculated daily exposure rates to nitrogen dioxide (NOz) and particulate matter (PM2.5) for each patient between 2016 and 2019 based on residential addresses and measured their blood black carbon levels. Long-term exposure to these pollutants was associated with an increased risk of being admitted to an intensive care unit, but even short-term exposure (increases in pollutants a week before hospitalization) led to longer hospitalizations by an average of more than four days. Notably, this was approximately equivalent to the effect of a ten-year increase in age. 

The researchers proposed three potential mechanisms that may explain the effect they found: 

  1. Air pollution exacerbates comorbidities and other respiratory conditions that are associated with poor COVID-19 outcomes. 
  2. Air pollution can modify immune system responses, reducing the body’s capability to defend itself against a COVID-19 infection.
  3. Air pollution may reduce the effectiveness of defense mechanisms in the respiratory system (such as the mucus membranes of the pulmonary tract), resulting in a more severe disease progression. 

After controlling for other potentially confounding factors such as BMI and comorbid conditions, researchers found that this effect was even more pronounced in men than in women. 

Air Purifiers for Reducing Air Pollution Exposure and COVID-19 Spread

Reducing your exposure to airborne pollutants can decrease the risk of severe health complications from COVID-19. Indoor air can be as much as fifty times more polluted than outdoor air.

To effectively protect yourself against harmful pollutants and pathogens indoors, consider adding a portable room air purifier that uses both factory-tested and certified HEPA filters (which trap particulate matter, including black carbon and infected COVID-19 droplets) and activated carbon filters (which remove gaseous pollutants such as ozone, sulfur dioxide, nitrogen dioxide, and volatile organic compounds). Premium air purifiers such as Camfil’s medical-grade City M air purifier provide homes, offices, classrooms, healthcare facilities, and more with the circulation and filtration necessary to improve air quality and can plug into standard electrical outlets for easy installation. 

About Camfil Clean Air Solutions

For more than half a century, Camfil has been helping people breathe cleaner air. As a leading manufacturer of premium clean air solutions, we provide commercial and industrial systems for air filtration and air pollution control that improve worker and equipment productivity, minimize energy use, and benefit human health and the environment. We firmly believe that the best solutions for our customers are the best solutions for our planet, too. That’s why every step of the way – from design to delivery and across the product life cycle – we consider the impact of what we do on people and on the world around us. Through a fresh approach to problem-solving, innovative design, precise process control, and a strong customer focus we aim to conserve more, use less and find better ways – so we can all breathe easier.

The Camfil Group is headquartered in Stockholm, Sweden, and has 30​ manufacturing sites, six R&D centers, local sales offices in 35+ countries, and about 5,600 employees and growing. We proudly serve and support customers in a wide variety of industries and in communities across the world. To discover how Camfil USA can help you to protect people, processes and the environment, visit us at 



Media Contact: 

Lynne Laake 

Camfil USA Air Filters 

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