This trend was confirmed by binary logistic regression, indicating that low number of vaccine doses (OR 0.194; 95% CI 0.074 to 0.511; p=0.001), IgG levels against SARS-CoV-2 S1 protein (OR 0.691; 95% CI 0.508 to 0.941; p=0.019), neutralizing capacity (NT50) of IgG against SARS-CoV-2 (OR 0.977; 95% CI 0.954 to 1.000; p=0.046), MIG/CXCL9 levels (OR 0.869; 95% CI 0.759 to 0.995; p=0.042), MPIF/CCL23 levels (OR 0.552; 95% CI 0.311 to 0.979; p=0.042) were correlated with the occurrence of LC. The gene discussed is CCL23; the disease is laryngotracheoesophageal cleft.