As students return to school from summer break, educators, administrators, and support staff ensure the learning environment is safe from infectious disease outbreaks. From kindergarten classrooms filled with tactile exploration to the close social interaction in high schools, where students share devices and meals during and after school, each grade presents its own opportunities. The following evidence‑based practices offer a strong foundation for actionable prevention.

Hand Hygiene First

Consistent, proper handwashing remains the most effective strategy for reducing gastrointestinal and respiratory illnesses in school settings. The CDC emphasizes teaching and reinforcing washing with soap and water for at least 20 seconds, building hygiene reminders directly into daily routines such as after bathroom breaks, before lunch, and after recess.¹ Younger students and those with special needs will benefit from coaching and supervision to ensure thorough hand washing and complete drying, an often-overlooked step because germs spread more easily on wet surfaces.¹ Hand sanitizer containing at least 60% alcohol should supplement, not replace, soap and water, especially when sinks are available.¹

Clean Learning Environment

Routine cleaning and disinfection of surfaces is essential for preventing the spread of infections. Daily cleaning of desks, chairs, doorknobs, faucets, electronics, and other frequently touched and shared items is recommended. Increase cleaning frequency during periods of elevated illness, like cold and flu season.² Electronic devices are an area of particular concern in modern classrooms. They should be cleaned and disinfected using Environmental Protection Agency (EPA)-approved products compatible with keyboards, touchscreens, and tablets.³ Compatibility information can be obtained from the equipment manufacturer.

Air Quality

During cold and flu season, improving air quality can meaningfully reduce the risk of respiratory infection outbreaks; the goal is to dilute the room air with as much outside air as possible. Improve ventilation by optimizing HVAC function, opening classroom and bus windows when safe, and using fan‑assisted airflow. These practices dilute airborne particles and reduce the risk of respiratory transmission.² Air ducts, intake, and exhaust grates must be kept clean and unobstructed.⁴

Portable air cleaners and air sanitizing sprays can supplement the HVAC system when used according to the manufacturer’s instructions.^5,6 However, their mechanisms of action have inherent shortcomings; many lack rigorous testing and validation metrics. They should not replace core strategies such as ventilation and surface cleaning.^4,6

Monitoring Illness and Absenteeism

The early detection of outbreaks relies on monitoring student (and staff) absenteeism. Research has shown that changes in absenteeism related to respiratory symptoms can correlate with community influenza trends.⁷ Schools should work closely with county health departments to interpret illness patterns when gastrointestinal or respiratory complaints are clustering.

CDC guidance recommends embedding an infectious disease section within the school’s Emergency Operations Plan. This section should outline protocols for monitoring illnesses, communicating with families, and activating enhanced preventive measures or temporary closure considerations during outbreaks.⁸

When Students and Staff are Sick

It is challenging to balance public health priorities, educational needs, and parental satisfaction, particularly when deciding whether a student should be sent home. CDC recommends excluding students and staff who exhibit fever, repeated vomiting, significant diarrhea, draining wounds, or worsening respiratory symptoms not attributable to allergies.⁹ Schools can expect some level of mild illness throughout the year; however, symptoms that impair participation or present infection risk justify time at home. Return-to-school criteria should be clearly communicated to families and staff and enforced to maintain consistency and reduce confusion. Schools must be staffed to support families facing childcare challenges and to help students maintain educational continuity when illness keeps them at home. Without such programs in place, students will frequently show up sick, leading to transmission and outbreaks.

Vaccination

Vaccination remains one of the most powerful preventive tools in pediatric health. It reduces illness, decreases absenteeism, and lowers the likelihood of outbreak-related closures.¹⁰ State laws mandate vaccinations for K–12 students across public and private schools, with medical exemptions universally available and religious or philosophical exemptions permitted in some jurisdictions.^8,9,11 Schools should ensure families understand these requirements and the process for submitting necessary documentation.

We are experiencing an ongoing decline in routine childhood vaccination, particularly after the COVID‑19 pandemic. Vaccine hesitancy is primarily driven by safety concerns/misinformation, philosophical beliefs, and lack of access in low-income, uninsured, or minority households. These factors have left students more vulnerable to a slew of vaccine‑preventable diseases.¹² We see the effects of this drop in vaccine coverage in outbreaks of diseases like measles and whooping cough.

Food Safety in School Meals and Packed Lunches

Outbreak prevention extends to the realm of food safety. Millions of meals are served through school nutrition programs each year, creating opportunities for foodborne illness if proper controls are not followed.¹³ USDA guidance recommends building a food safety culture rooted in hazard analysis and critical control point principles. Schools must implement food safety programs covering every location where food is stored, prepared, or served.¹⁴

Creating a culture of food safety requires engaging teachers, administrators, parents, and students¹⁵. Parents who send packed lunches should be reminded to use ice packs and insulated containers to maintain safe temperatures until mealtime. When possible, students may need access to microwave ovens to reheat food. School cafeterias, meanwhile, must ensure proper temperature control, safe storage, and adherence to hygiene protocols that prevent cross‑contamination.¹³

Conclusion

Preventing outbreaks in K–12 schools relies on a comprehensive strategy grounded in evidence‑based health practices, consistent communication, and strong collaboration across the school community. Educators, administrators, and support staff should model the healthy behaviors they expect from students, reinforcing the value of cleanliness, personal responsibility, and empathy for peers’ health. Encouraging students not to share drinks or food, teaching proper cough etiquette, and reminding them to speak up when they feel unwell all contribute to a safer environment.

By prioritizing hand hygiene, maintaining clean environments, improving air quality, monitoring illnesses, enforcing vaccination requirements, supporting food safety, and fostering responsible student behavior, create healthier learning spaces where children can thrive academically and socially.

References

1. About Hand Hygiene in Schools and Early Care and Education Settings. CDC. Published October 25, 2024. Accessed July 20, 2026. https://www.cdc.gov/clean-hands/prevention/about-hand-hygiene-in-schools-and-early-care-and-education-settings.html
2. Everyday Actions for Schools to Prevent and Control the Spread of Infections. CDC. Published May 12, 2026. Accessed July 20, 2026. https://www.cdc.gov/children-and-school-preparedness/infection-prevention/actions.html
3. Cleaning and Disinfecting in School Classrooms. Published August 7, 2020. CDC. Accessed July 2026. https://stacks.cdc.gov/view/cdc/91746/cdc_91746_DS1.pdf
4. Take Action to Improve Indoor Air Quality in Schools. United States Environmental Protection Agency. Accessed July 20, 2026. https://www.epa.gov/iaq-schools/take-action-improve-indoor-air-quality-schools
5. EPA Registers Air Sanitizer for Residential and Commercial Use Against Influenza and Coronavirus. United States Environmental Protection Agency. Updated March 23, 2026. Accessed July 20, 2026. https://www.epa.gov/pesticides/epa-registers-air-sanitizer-residential-and-commercial-use-against-influenza-and
6. Residential Air Cleaners: A Technical Summary, 3rd ed. United States Environmental Protection Agency. Published July 2018. Accessed July 20, 2026. https://www.epa.gov/sites/default/files/2018-07/documents/residential_air_cleaners_-_a_technical_summary_3rd_edition.pdf
7. Temte J, Barlow S; yenlik Zheteyeva, et al. Cause-Specific School Absenteeism Monitoring Identifies Community Influenza Outbreaks. Online J Public Health Inform. 2018;10(1):e103. Published 2018 May 30. Accessed July 20, 2026. doi:10.5210/ojphi.v10i1.8757
8. Preventing Spread of Infections in K‑12 Schools. CDC. Published May 12, 2026. Accessed July 20, 2026. https://www.cdc.gov/children-and-school-preparedness/infection-prevention/index.html
9. When Students or Staff Are Sick. CDC. Published October 28, 2024. Accessed July 20, 2026. https://www.cdc.gov/children-and-school-preparedness/php/interventions/when-students-or-staff-are-sick.html
10. Path Forward: Every Student Every Day. CDC. Accessed July 20, 2026. https://www.cdc.gov/vaccines/partners/downloads/cta-school-health-partners.pdf
11. State School Immunization Requirements and Vaccine Exemption Laws. CDC. Published February 2022. Accessed July 20, 2026. https://www.cdc.gov/phlp/docs/school-vaccinations.pdf
12. McKee C, Bohannon K. Exploring the Reasons Behind Parental Refusal of Vaccines. J Pediatr Pharmacol Ther. 2016;21(2):104-109. doi:10.5863/1551-6776-21.2.104
13. Food Safe Schools: Creating a Culture of Food Safety. Food and Nutrition Administration. Accessed July 2026. https://www.fna.usda.gov/fs/foodsafeschools
14. Guidelines on Developing a School Food Safety Program Based on HACCP Principles. United States Department of Agriculture. Published June 2005. Accessed July 20, 2026. https://www.usda.gov/sites/default/files/guidance-documents/fns.foodsafety-HACCPguidance.pdf
15. Creating a Culture of Food Safety & Using the Action Guide. Food and Nutrition Administration. Updated January 7, 2025. Accessed July 20, 2026. https://www.fna.usda.gov/fs/foodsafeschools/how