A strep carrier is an individual who carries the bacteria that causes strep throat but never becomes sick with the illness. When a family experiences repeated bouts of strep, someone in the family may be a carrier, according to MedlinePlus.
Treating the carrier can help prevent others from becoming sick with strep throat. Strep throat is caused by a germ known as Group A Streptococcus. This bacteria spreads from one person to another via bodily fluids from the saliva or nose, according to MedlinePlus. Symptoms of strep throat include a sore throat that may be red or have white patches, painful swallowing, tender or swollen glands in the neck, chills and fever.