Disinfecting the Home: Myths, Policies and Best Practices

June 29, 2022

A spray bottle next to three sponges.
Source: Rawpixel.
In the early stages of the COVID-19 pandemic, stores saw devastating shortages of essential supplies, like hand sanitizer, disinfectant wipes and cleaning products. As the first cases emerged, many questions arose about the survival of the SARS-CoV-2 virus on surfaces. Thus, many people purchased dozens of cleaning products with the hope of eradicating the virus from groceries, packages and frequently touched surfaces in the home. Eventually, consumers emptied shelves previously teeming with disinfectant sprays and antibacterial wipes.  

“People were leaving packages on their porches for days; they were wiping down their packages, disinfecting every product that they bought at the grocery store,” Jeffrey Van Komen, Ph.D., senior scientist for Procter and Gamble, said. In many cases, it is considered best practice to disinfect surfaces that are frequently touched, like doorknobs and cell phones, to mitigate the spread of disease within a community. Still, scientists worry—especially with the recent global spread of mpox virus (formerly called monkeypox virus) and discussion of future pandemics—that the overuse of cleaning products will contribute to significant supply chain shortages, exposure to toxins and antimicrobial resistance.  

A Call for Evidence-Based Hygiene Practices  

Why is the public determined to remain in the 20th Century with outdated practices for good hygiene? That’s what Elizabeth Scott, Ph.D., co-director and founder of the Simmons Center for Hygiene and Health in Home and Community, would like to know.  

Modern advice on hygiene and infection control was first recorded in the mid-19th century in Europe and the U.S. Described as the “age of sanitary reformers,” the sanitary reform movement and the cleaning and disinfectant industry grew in the late 19th and early 20th centuries. According to Scott, “The middle of the 20th century was an era of great optimism, it was the era of antibiotics. There was a sense that we didn’t need to be concerned about infections anymore, we could treat them all.”    

In the 20th century, many people practiced “deep cleaning” (e.g., disinfecting all surfaces in the home, including floors and walls, and washing items, like couch cushions, that can be removed from furniture) in the home to ward off infection. This non-evidence-based risk assessment indicated that the public assumed surfaces always harbored germs and pathogens that needed to be eliminated. However, Scott explained this is not an evidence-based approach. “The daily, weekly or monthly practices that we carry out in homes and community settings make us feel better, but they don’t actually reduce risk,” she explained. 

Conversely, targeted hygiene, a technique that uses evidence-based risk assessment, considers the hazard (i.e., probability of pathogens being present at key moments of contact) and the exposure (i.e., probability of the spread of pathogens that may cause infections) and uses information collected from such analyses to inform when and how hygienic practices should be conducted. When applied in home and hospital settings, targeted hygiene "prevents the spread of harmful microbes in a targeted manner. It addresses sustainability issues, it avoids the overuse of chemicals and microbicides, it sustains exposure to beneficial microbes and it recognizes that [cleaning and hygiene] are a shared responsibility.”  

According to Scott, exposure to pathogens most likely occurs from contact with someone coughing or sneezing, bathrooms, raw food, pets and domestic animals, frequently touched surfaces (e.g., faucet handles), handling soiled clothing and linens, eating with bare hands, handling domestic waste and caring for an infected family member. Floors and walls are considered low-risk surfaces for exposure, while frequently touched surfaces (e.g., television remotes, door handles) are surface- and agent-dependent for exposure. For example, Scott explained, “There’s a greater risk of transmitting norovirus and cold virus via surface contact because [these viruses] are very robust in the environment and have a low infectious disease dose.” Conversely, data suggest that an individual is more likely to contract COVID-19 from the air than surface contact. For other pathogens, like mpox, surface contact poses a greater risk for transmission. In addition to large respiratory droplets, mpox may be transmitted via broken skin or small wounds that aren't always visible, therefore disinfecting frequently touched surfaces is critical to mitigating the spread of the virus. 

Frequently touched surfaces, like doorknobs and electronics, can contribute to virus exposure.
Frequently touched surfaces, like doorknobs and electronics, can contribute to virus exposure.
Source: Image adapted from NCBI: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7236697/

In April 2021, a joint report from the International Association for Soaps, Detergents and Maintenance Products and the International Scientific Forum on Home Hygiene surveyed 23 countries in Europe to determine the level of understanding between hygiene and cleaning practices. The study had over 4,000 participants, with 87% acknowledging that cleaning and hygiene in the home are important. However, over 30% of participants did not understand the difference between cleaning and hygiene. Cleaning is specific to the removal of dirt or waste, while hygiene encompasses disease prevention via several practices, including cleaning. Some participants concluded that a surface which appeared to be clean was in fact hygienic, and that is not the case. Scott explained these data provide a benchmark for the level of understanding that individuals have regarding cleaning and hygiene in terms of at-home practices and what education needs to be provided to improve community health. “If we don’t know what people are thinking, we can’t give them information that they can act upon,” she said. For emerging pathogens other than COVID-19, education on different disinfecting practices for viruses that are transmissible through skin contact will be integral to mitigating their spread. 

Tips For Applying Evidence-Based Hygeine Practices

The Centers for Disease Control and Prevention (CDC) provides guidance on disinfecting surfaces, including hard surfaces, household items and upholstered furniture and advises limiting the use of products that double as antimicrobials, as overusing such products can contribute to antimicrobial resistance. Verifying that antimicrobials used in the home are legitimate, and not counterfit products, is a good place to start. Pay close attention to the types of surfaces the disinfectant can be used on, the amount of time the disinfectant should stay wet on the surface and if the product’s directions recommend removing dirt or waste from the surface before using the disinfectant.

Planning for Emerging Infections 

As the landscape of disease continues to evolve, the EPA’s Emerging Viral Pathogen Guidance and Status for Antimicrobial Pesticides allows companies to voluntarily pre-register their products in preparation of an emerging pathogen. The companies can present efficacy data, and the EPA may grant the company the ability of make off-label claims about the product.

There are currently 3 active emerging viral pathogen policies:

  1.  List N catalogs disinfectants for COVID-19, including its variants, and lists products containing active ingredients like quaternary ammonium, hydrogen peroxide and hypochlorous acid.
  2.  List O focuses on pathogens pertinent to veterinary care, including rabbit hemorrhagic disease virus, and lists products that include active ingredients such as sodium hypochlorite, thymol and sodium dichloroisocyanurate.
  3. List Q includes disinfectants for emerging viral pathogens, like mpox, with active ingredients such as chlorine dioxide, isopropyl alcohol and sodium chloride. Wipes, ready-to-use and dilutable products are included on these lists.    

Mpox is classified as a “Tier 1” virus (enveloped virus) by the EPA, and since it can be spread through fomite transmission, products classified in List Q are recommended for treating surfaces in the home that may have been contaminated by the virus. The CDC recommends washing any fabrics or linens, like towels or pillowcases, before cleaning a particular area or room that was exposed to the virus. Additionally, when sharing spaces with someone who is infected with mpox, the CDC recommends disinfecting all household items and frequently touched surfaces.

With the global spread of mpox, Van Komen explained that concern regarding the spread of the virus is coupled with worry that cleaning products will be as hard to find as they were at the start of the COVID-19 pandemic, and that in response, counterfeit products will be marketed on the internet. “Under-registered products and the last line of the proliferation of unregistered pesticides in the e-commerce marketplace, especially during this unprecedented time, pose a significant and immediate health risk to consumers, children and pets.” Van Komen emphasized the importance of both consumers and policymakers taking note of supply chain shortages and poison control concerns that were heightened in early 2020 in order to be mindful of how future pandemics impact the availability of cleaning products and shape best public health practices.  

Research in this article was presented at ASM Microbe, the annual meeting of the American Society for Microbiology, held June 9-13, 2022, in Washington, D.C. 

Author: Leah Potter, M.S.

Leah Potter, M.S.
Leah Potter joined ASM in 2022 as the Communications Specialist.