Strep Carrier Testing and Management
Routine testing and treatment of asymptomatic streptococcal carriers is not recommended, as carriers are at very low risk for complications and do not require antimicrobial therapy except in specific high-risk situations. 1
Who is a Streptococcal Carrier?
- Carriers have Group A streptococci present in their pharynx but show no evidence of immunologic response to the organism. 1, 2
- Up to 20% of asymptomatic school-aged children may be streptococcal carriers during winter and spring in temperate climates. 1, 2
- Carriers may be colonized for several months and can experience intercurrent viral pharyngitis during this period, which may be confused with acute streptococcal infection. 1
Why Carriers Should NOT Be Treated Routinely
- Carriers are at very low risk (if any) for developing suppurative or nonsuppurative complications such as acute rheumatic fever. 1, 2
- Carriers are unlikely to spread the organism to their close contacts. 1, 2
- It is much more difficult to eradicate Group A streptococci from carriers than from patients with acute infections, even with appropriate antibiotics. 1
When to Test for Carrier State
- Routine post-treatment testing of asymptomatic patients is NOT recommended after completing antibiotic therapy. 1, 3
- Testing should only be performed for patients who remain symptomatic or whose symptoms recur after treatment. 4
- Follow-up testing may be considered in special circumstances: 1
- During a community outbreak of acute rheumatic fever, post-streptococcal glomerulonephritis, or invasive Group A streptococcal infection
- During an outbreak in a closed or semi-closed community
- When the patient has a personal or family history of acute rheumatic fever
When Carriers SHOULD Be Treated (Exceptions)
Antibiotics may be considered for carriers in these specific situations: 1
- During a community outbreak of acute rheumatic fever, acute post-streptococcal glomerulonephritis, or invasive Group A streptococcal infection 1
- During an outbreak of Group A streptococcal pharyngitis in a closed or partially closed community 1
- When the patient has a personal or family history of acute rheumatic fever 1, 2
- When the patient or family has excessive anxiety about Group A streptococcal infections 1
- When tonsillectomy is being considered only because the patient is a chronic carrier 1
Treatment Regimens for Carriers (When Indicated)
If treatment is warranted, use carrier-specific regimens that are more effective at eradication: 1
- Clindamycin: 20-30 mg/kg/day in 3 divided doses (maximum 300 mg per dose) for 10 days 1
- Penicillin V with rifampin: Penicillin V 50 mg/kg/day in 4 divided doses PLUS rifampin 20 mg/kg/day in 2 divided doses for 4 days 1
- Amoxicillin-clavulanic acid: 40 mg/kg/day in 3 divided doses for 10 days (children) or 500 mg twice daily for 10 days (adults) 1
Management of Household Contacts
- Routine testing or treatment of asymptomatic household contacts is NOT recommended. 1, 2
- Testing household contacts should only be considered in rare situations when post-treatment testing of the index patient is indicated, and then only culture (not rapid testing) should be used. 1
Critical Pitfall to Avoid
Do not confuse an asymptomatic positive throat culture or rapid test with active infection requiring treatment. 4, 2 When a patient with recurrent pharyngitis tests positive for Group A streptococci, they are likely a carrier experiencing intercurrent viral infections rather than having repeated bacterial infections. 1 Unnecessarily treating these patients leads to antibiotic overuse without clinical benefit. 2