Ryan McKeen—the co-founder of a Glastonbury-based personal injury firm—did what the medical experts told him: He got vaccinated, wore masks and kept about 6 feet between him and others in public spaces to avoid contracting COVID-19.

But even though he took all the precautions the Centers for Disease Control and Prevention and state experts recommended, McKeen got news July 29 he never expected: He’d tested positive for the coronavirus after getting cold-like symptoms.