Yes, it is possible to carry the bacterium (group A streptococcus) that causes strep throat without developing symptoms. It is estimated that between five and 15 percent of children are carriers. These youngsters usually are not contagious, are not considered at risk of any health problems because they are "carriers," and do not require any treatment. In fact, pediatricians tell me that the greatest risk to carriers is the discovery that they are carriers and, as a result, might be treated repeatedly and unnecessarily with antibiotics.
Although strep throat itself is a relatively minor illness, it can lead to serious health problems later in life so it requires prompt diagnosis and treatment. Symptoms include fever, headache, a sore throat, and swollen and tender lymph nodes (glands) in the neck. These may not sound much different than the symptoms of a sore throat caused by a virus, which presents no long-lasting health risk. The only way to tell which kind of sore throat a child has developed is with a rapid strep test and/or throat culture.
When a strep infection causes symptoms, it must be treated with a course of antibiotics, usually penicillin. It is essential to complete the full course treatment prescribed by your doctor because an untreated or incompletely treated strep infection can lead to kidney problems or rheumatic fever, which can result in injury to the heart. These complications don't occur among carriers, which is why it isn't necessary to treat them with antibiotics.
Andrew Weil, M.D.