Should I change my toothbrush after a streptococcal (strep) infection?

Changing Toothbrush After Strep Throat Infection

While there is no specific guideline recommending toothbrush replacement after streptococcal pharyngitis, it is reasonable to replace your toothbrush after completing antibiotic treatment to reduce the theoretical risk of reinfection.

Evidence on Toothbrush Contamination

• Toothbrushes can become contaminated with various microorganisms, including streptococci, during normal use 1
• Studies have shown that used toothbrushes can harbor approximately 4 x 10³ colony-forming units (CFU) per milliliter of bacteria, with bacterial growth still present on bristles even after rinsing 1
• Streptococci can survive on toothbrushes, creating a theoretical risk of reintroduction of the pathogen after treatment 2

Impact on Reinfection Risk

• Research specifically examining the relationship between toothbrush replacement and strep throat recurrence found no significant difference in recurrence rates between patients who implemented hygienic measures (including toothbrush replacement) and those who did not 3
• The Infectious Diseases Society of America (IDSA) guidelines on streptococcal pharyngitis do not specifically mention toothbrush replacement as part of management 4
• Recurrence of streptococcal pharyngitis is more commonly attributed to:
  • Persistence of carriage during intercurrent viral infections 4
  • Noncompliance with prescribed antimicrobial regimens 4
  • New infections acquired from family, classroom, or community contacts 4

Practical Recommendations

• Replace your toothbrush after completing antibiotic treatment for strep throat as a reasonable precautionary measure 2
• If replacement is not possible, consider disinfecting your toothbrush using one of these effective methods:
  • Soaking in an antimicrobial mouthwash like Listerine for 20 minutes 1
  • Running through a normal dishwasher cycle 5
  • Microwaving on high power for 5 minutes (if toothbrush is microwave-safe) 5

Special Considerations

• Immunocompromised individuals should be more vigilant about toothbrush replacement, as they are at higher risk for invasive streptococcal disease 2, 6
• For patients with recurrent streptococcal infections, consider more frequent toothbrush replacement as part of overall hygiene measures 2
• Streptococcal carriers (those with the bacteria present but without symptoms or immune response) are unlikely to spread the organism to close contacts and are at low risk for complications 4

Important Caveats

• Toothbrush replacement alone is unlikely to prevent recurrence if other factors are present (e.g., inadequate antibiotic treatment, household carriers) 3
• The American Heart Association and Infectious Diseases Society of America guidelines do not specifically address toothbrush replacement after streptococcal infection 4
• Focus should remain on completing the full course of prescribed antibiotics, which is the most important factor in eradicating group A streptococcal infection 4