Prevalence of CF was assessed using an interrupted time series analysis, comparing pre- and post-COVID-19 years.<h4>Results</h4>In 2021, CF availability was 31.5 percentage points lower than the expected level if the pre-COVID trend had continued (<i>p</i> < 0.001).<h4>Discussion</h4>Findings suggest that COVID-related school nutrition policy changes, including Universal Fee Meals and increased reimbursements, likely reduced CF availability. The gene discussed is CFTR; the disease is cystic fibrosis.