Photo credit: Purell

The COVID-19 pandemic reinforced the critical importance of implementing evidence-based hygiene practices for effective infection prevention in schools. In the years preceding the pandemic, an estimated 69 percent of children in the U.S. missed at least one school day every year due to illness, with 15 percent missing six or more days and up to 189 million school days lost due to the common cold alone each year.

During the unprecedented 2020-21 academic year, in an effort to enable schools to reopen and stay open safely, infection prevention approaches were advanced to include the practices of wearing masks, physical distancing, and frequent hand and surface hygiene. These same approaches were largely successful in not only preventing the spread of SARS-CoV-2, the virus responsible for the COVID-19 pandemic, but also reduced the transmission of other common school-related illnesses such as colds, flu, and gastrointestinal (GI) illness.

According to the Centers for Disease Control and Prevention (CDC), cases of the flu remained very low during the winter of 2020-21, with only about 2,000 cases recorded since late September 2020, compared to an average number of 206,000 cases over the same period in recent years. Part of this decrease is likely attributable to a higher-than-normal influenza vaccination rate. However, like COVID-19, influenza is a respiratory disease, and the same infection mitigation approaches adopted to prevent the transmission of COVID-19 likely also prevented the spread of the flu and other common communicable diseases in schools.

There is an emerging concern amongst some scientists that susceptibility to rhinovirus and influenza virus (the viruses that cause the common cold and flu, respectively) will increase post-pandemic, due to lowered immunity stemming from reduced exposure to the latest cold and flu strains during the COVID-19 pandemic. However, with increased availability of COVID-19 vaccines and decreasing cases in the U.S., the CDC will likely continue to evolve its infection prevention guidance to schools, likely relaxing some hygiene recommendations. As schools prepare for the 2021-22 academic year, it is critical to remain vigilant with a standardized level of basic hand and surface hygiene to not only maintain the low incidence of COVID-19 throughout the remainder of the pandemic but also to continue to prevent surges of common school-related diseases such as colds, flu, and GI illnesses.

Hand hygiene practices reduce the risk of COVID-19 and other common school illnesses. Hand hygiene is the single most effective way to both prevent infection and stop the spread of germs in schools. Several studies have demonstrated that proper hand hygiene in schools can significantly reduce illness and absenteeism due to gastrointestinal or respiratory illnesses. For effective infection control in schools, the CDC recommends practicing good hand hygiene, often and at key moments during the day. This guidance includes washing hands with soap and water for at least 20 seconds or using an alcohol-based hand sanitizer (ABHS) with at least 60 percent ethyl or isopropyl alcohol if soap and water are not readily available. Hand sanitizers are over-the-counter (OTC) drugs regulated by the U.S. Food and Drug Administration (FDA). ABHS helps reduce bacteria that potentially can cause disease. Evidence-based hand hygiene programs have been proven effective in reducing germs and infection risk in schools and day care centers.

Not all hand sanitizers are proven to be safe and effective. During the COVID-19 pandemic, most schools adopted increased hygiene practices; however, widespread availability of inferior and unproven products has led to concerns about safety, compliance, and overall germ-killing efficacy. In a recent survey of educators, almost half of educators responded they were unlikely to use a poor-quality hand sanitizer, with up to 70 percent reporting unlikeliness to use a sanitizer if it irritates skin, smells bad, or has a sticky consistency. In the same study, 73 percent of educators reported concern that students would not use a provided sanitizer due to poor aesthetic qualities. During the pandemic, the FDA created a temporary policy for widespread production of sanitizer to meet demand. However, concerns of contaminants, inadequate levels of active ingredient (ethyl alcohol or isopropyl alcohol), labels with false or unproven claims have since surfaced, with nearly 250 products now banned by the FDA.

When choosing a hand sanitizer, the following guidelines should be followed to ensure safe and effective products are available for use in schools:

1. Choose an ABHS containing at least 60 percent ethyl alcohol or 70 percent isopropyl alcohol for proven efficacy against germs.
2. Ensure the product is in the original packaging with appropriate labeling and is not on the FDA-banned list of sanitizers.
3. Avoid hand sanitizers with poor aesthetic qualities, such as an undesirable smell, poor product consistency, stickiness, or those that irritate or dry hands.
4. Avoid mixing different sanitizer formulations.
5. Consider optimal placement of hand sanitizers— where sinks and facilities are not readily available and/or traffic flow does not permit proper washing with soap and water.
6. Consider the use of ABHS in addition to soap and water for occasions and settings where germ transmission risk may be higher; for example, in high traffic areas, after restroom use, and/or during food handling and consumption.

School surfaces are reservoirs for germs. Bacteria and viruses can readily survive on objects and surfaces, thus having the potential to be transferred to an individual’s hands upon touch, perpetuating the germ cycle. These contaminated objects or surfaces, referred to as fomites, play a role in the spread of respiratory viruses such as SARS-CoV-2, even though aerosols and respiratory droplets are the primary transmission routes. Despite regular surface cleaning, germs are prevalent in the school setting. According to ABC News, the objects in a typical school are contaminated with up to 15,000 germs. A study in the Journal of School Nursing demonstrated that student desktops were one of the most virus-contaminated surfaces in the average school setting, with five out of 27 desktops contaminated with the virus that causes the flu. A separate study of high touchpoint handrails found norovirus (the germ that causes GI illness) on up to 22 percent of surfaces. Some germs, like SARS-CoV-2, can persist up to 28 days on surfaces, giving ample time for fomite transmission. With their shared objects, close facilities, and young inhabitants, schools may represent places where the risk of fomite transfer is higher than at other types of facilities.

Surface disinfection is a powerful strategy to eliminate germs on surfaces. A study in schools more than a decade ago demonstrated that the use of disinfectant wipes reduced absenteeism by more than 50 percent. More recently, modeling of surface contamination by SARS-CoV-2 revealed that frequent disinfection of high-touch surfaces has the potential to reduce COVID-19 transmission in school and day care settings. While the CDC continues to refine surface disinfection guidelines for facilities to prevent the spread of COVID-19, the organization acknowledges there are times when it may be important to more frequently clean AND disinfect surfaces. These include when high transmission rates of infectious diseases occur (COVID-19, cold, flu, GI illness) and when mask usage and hand hygiene are absent, infrequent, or improperly practiced, many of which are common in school settings.

Safe environments can be maintained with EPA-approved low toxicity surface sanitization products. Schools are unique settings where vulnerable children are present for prolonged periods of time, and as such, toxicity from exposure to disinfectant chemicals may be increased, particularly in low-ventilation areas. Organizations that safeguard children’s health, such as the American Academy of Pediatrics and the CDC, recommend the selection of safer disinfectants from the EPA List N (believed to be effective against SARS-CoV-2), which have reduced health and environmental impacts and often have equivalent or greater efficacy on microorganisms. The following principles may guide the selection of appropriate safer disinfectants:

1. Lower-toxicity cleaning and disinfectant products do not have signal words like “Danger” or “Warning.”
2. EPA-listed disinfectants that contain active ingredients such as hydrogen peroxide, ethanol, and citric acid are believed to be less toxic, weak respiratory irritants or asthma triggers, and have no known carcinogenic, reproductive, or developmental effects.
3. Lower toxicity surface disinfectants can be identified using the EPA’s tiered toxicity categories, where toxicity category I is “Highly toxic and severely irritating” while toxicity category IV is “Practically non-toxic and not irritating. ”
4. Lower toxicity disinfectants typically lack cautionary statements like “causes eye irritation” and do not typically instruct to “wash hands thoroughly after use” or require surfaces to be rinsed after product use.

For more information and useful tips on reopening your K-12 facilities safely, visit the PURELL® Brand K-12 Well-Being Center at https://www.gojo.com/en/Industries/Education-K12/K-12-Well-Being-Center.

This article was sponsored by GOJO Industries, Inc., the makers of PURELL® hygiene solutions.

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