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Updated: Mar 15, 2026
Detection of Viruses from Bioaerosols Using Anion Exchange Resin
Published on: August 22, 2018
Generic aspects of the airborne spread of human pathogens indoors and emerging air decontamination technologies
M Khalid Ijaz1, Bahram Zargar2, Kathryn E Wright2
1RB, Montvale, NJ; Department of Biology, Medgar Evers College of the City University of New York (CUNY), Brooklyn, NY.
Abstract:
Indoor air can be an important vehicle for a variety of human pathogens. This review provides examples of airborne transmission of infectious agents from experimental and field studies and discusses how airborne pathogens can contaminate other parts of the environment to give rise to secondary vehicles leading air-surface-air nexus with possible transmission to susceptible hosts. The following groups of human pathogens are covered because of their known or potential airborne spread: vegetative bacteria (staphylococci and legionellae), fungi (Aspergillus, Penicillium, and Cladosporium spp and Stachybotrys chartarum), enteric viruses (noro- and rotaviruses), respiratory viruses (influenza and coronaviruses), mycobacteria (tuberculous and nontuberculous), and bacterial spore formers (Clostridium difficile and Bacillus anthracis). An overview of methods for experimentally generating and recovering airborne human pathogens is included, along with a discussion of factors that influence microbial survival in indoor air. Available guidelines from the U.S. Environmental Protection Agency and other global regulatory bodies for the study of airborne pathogens are critically reviewed with particular reference to microbial surrogates that are recommended. Recent developments in experimental facilities to contaminate indoor air with microbial aerosols are presented, along with emerging technologies to decontaminate indoor air under field-relevant conditions. Furthermore, the role that air decontamination may play in reducing the contamination of environmental surfaces and its combined impact on interrupting the risk of pathogen spread in both domestic and institutional settings is discussed.
Insights
Indoor air harbors numerous pathogens, including bacteria, viruses, and fungi. Understanding airborne transmission and decontamination is crucial for preventing disease spread in homes and institutions.
Area of Science:
- Environmental microbiology
- Infectious disease transmission
- Public health
Background:
- Indoor air serves as a significant transmission route for various human pathogens.
- Airborne pathogens can contaminate surfaces, creating an "air-surface-air" transmission cycle.
- Understanding this cycle is vital for controlling infectious diseases in built environments.
Purpose of the Study:
- To review airborne transmission of human pathogens in indoor environments.
- To discuss methods for studying and decontaminating airborne pathogens.
- To evaluate the role of air decontamination in reducing pathogen spread.
Main Methods:
- Review of experimental and field studies on airborne pathogen transmission.
- Analysis of methods for generating and recovering airborne microbes.
- Critical review of regulatory guidelines and microbial surrogates.
- Presentation of recent advancements in aerosol generation and air decontamination technologies.
Main Results:
- Indoor air facilitates the spread of diverse pathogens including bacteria (e.g., Legionellae), viruses (e.g., Coronaviruses), fungi (e.g., Aspergillus), and spore-formers (e.g., Clostridium difficile).
- Factors influencing microbial survival in indoor air were discussed.
- Effectiveness of air decontamination in reducing surface contamination and overall pathogen risk was evaluated.
Conclusions:
- Airborne transmission is a critical pathway for pathogen spread indoors.
- Advanced methods for studying and decontaminating indoor air are emerging.
- Air decontamination strategies can interrupt pathogen transmission cycles, reducing risks in domestic and institutional settings.
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