Every August and September, schools reopen and respiratory illness surges. It happens every year, and 2026 will not be an exception.
Health officials expect an early and robust rhinovirus season, particularly among preschoolers and early elementary children. RSV, influenza, and COVID variants are expected to follow in October and November. Separately, the ongoing measles outbreak in Virginia is a reminder that vaccine-preventable diseases are still circulating and that back-to-school vaccination checks matter.
What to Expect This Season, and When
Rhinovirus (the common cold): late August
Rhinovirus is almost always the first respiratory virus to surge when schools reopen. In children under 5, it can cause more than just a runny nose: rhinovirus can trigger wheezing episodes and croup, particularly in children with a history of reactive airway disease. For most school-age children, it produces a typical cold lasting 7 to 10 days.
Post-pandemic patterns suggest rhinovirus activity has become earlier and stronger than pre-2020 baselines. Expect the first classroom cold wave in the third or fourth week of August.
RSV: September through October
Respiratory syncytial virus is the most serious respiratory illness for infants and children under 2. In older children and adults it presents like a cold. In very young infants it can cause bronchiolitis, a lower respiratory infection that sometimes requires hospitalization.
RSV season has shifted somewhat post-pandemic, and 2026 data suggests an earlier-than-historical start. Parents of infants born in spring 2026 should discuss with their pediatrician whether their child qualifies for nirsevimab (Beyfortus), the RSV preventive antibody now recommended for infants under 8 months entering their first RSV season. Track RSV activity at /outbreaks/acute-bronchiolitis.
Influenza: October through February, with early activity possible
Influenza typically peaks between November and February, but early activity in October is not unusual. The 2025 to 2026 flu season was moderate. Annual vaccination remains the most effective protection. Flu shots for the 2026 to 2027 season will be available by September.
COVID-19: year-round
COVID-19 continues circulating at endemic levels. Variant composition changes seasonally. Back-to-school gatherings can accelerate local spread, but severe outcomes in school-age children without underlying conditions remain rare. Updated vaccines are typically available each fall.
Measles: Check Vaccination Status Before School Starts
The 2026 Virginia measles outbreak expanded to multiple counties, with cases concentrated in unvaccinated children ages 5 to 12. Measles is highly contagious and spreads easily in school settings.
Before school starts, verify that your child has received two doses of the MMR vaccine. The first dose is typically given at 12 to 15 months. The second dose is given at 4 to 6 years. Children who are behind should catch up before school reopens.
If you are unsure of your child's vaccination status, your pediatrician can check records or order a titer test.
When to Keep Your Child Home
This is one of the most common questions parents ask, and the answer has not changed despite post-pandemic pressure around attendance policies.
Keep your child home if they have:
- A fever above 100.4 degrees F, until fever-free for 24 hours without fever-reducing medication
- Active vomiting or diarrhea
- A diagnosed contagious illness: strep throat, pink eye, influenza, or similar
- Symptoms severe enough to prevent normal participation in class
A mild runny nose without fever, in a child who feels well and is acting normally, is generally not a reason to stay home. Schools and pediatric guidelines both support this distinction. When in doubt, call your child's school to ask about their current illness policy, which may have changed since the pandemic.
How to Prepare Before August
A few concrete steps reduce your child's risk and reduce the disruption when illness does arrive:
- Confirm vaccinations are current: MMR, flu shot (available September), and any catch-up vaccines your pediatrician recommends
- Teach proper handwashing: 20 seconds with soap and water, before eating and after using the bathroom, is still the single most effective prevention measure
- Pack hand sanitizer: Alcohol-based hand sanitizer in the school bag for moments when soap and water are not available
- Know your school's illness notification system: Some schools use apps or email to alert parents when a reportable illness is confirmed in a classroom
- Have a backup care plan ready: Illness will happen. Having a plan before school starts prevents scrambling
Track What Is Going Around in Your Area
Virus Watcher monitors school-relevant illness year-round, including measles, influenza, norovirus, and RSV (acute bronchiolitis). Starting in late August, the app will show rising signals in states where back-to-school illness is ramping up.
You can set alerts for specific diseases in your state so you know when activity is elevated before your child's school sends home a notice.
