A soldier wounded in Iraq and a pregnant woman in Louisiana are overcome by a strange infection. Doctors discover that they are both infected with Acinetobacter baumannii, a mutating bacteria. Also known as iraqibacter, Acinetobacter baumannii is prevalent in combat hospitals, and has migrated to hospitals in the United States. Also in the program, two healthy, athletic boys are stricken with a mysterious infection. Tests reveal that both boys are infected with MRSA, a strain of staph bacteria that is resistant to antibiotics. As more cases are reported across the country, the CDC fears an epidemic.