Developing alternative, non-antibiotic treatments for certain “self-limiting infections” may help preserve the effectiveness of antibiotics for patients who need them most, according to a new paper published in PLOS Biology.
While drug development has been focused on antibiotic therapy for severe infections (eg, sepsis), researchers from the Georgia Institute of Technology note that growing resistance is primarily the result of fighting many small infections. In their essay, they identify infections that are clinically mild but contribute greatly to resistance evolution. These include urinary tract infection, pharyngitis/tonsillitis, otitis, upper respiratory tract infection, bronchitis, and sinusitis.
“Antibiotic prescriptions against those smaller ailments account for about 90% of antibiotic use, and so are likely to be the major driver of resistance evolution,” said Sam Brown, an associate professor in Georgia Tech’s School of Biological Sciences. For example, a broad-spectrum antibiotic can eliminate more of the less harmful bacteria, allowing the dangerous and stronger bacteria to propagate. Patients who are initially treated for a throat infection may end up with drug-resistant gut bacteria; these superbugs have gained high resistance from antibiotic courses prescribed for small infections.
Refocusing drug development towards these mild infections may help preserve the efficacy of existing antibiotics. In their paper, the authors assess the suitability of streptococcal pharyngitis for alternative therapeutics. “Asymptomatic carriage of [Group A streptococci] is common and does not normally warrant antibiotic treatment, as the risks for complications and transmission are considered low,” write the authors, “One potential strategy would therefore be to develop antivirulence drugs that turn symptomatic infection into asymptomatic carriage, decrease the symptoms and risks associated with infection, or help the immune system to clear the bacteria.” In addition, developing a spray-on treatment with bacteriophages may be another approach.
The authors conclude by saying that in addition to using other strategies (shorter antibiotic courses, use of narrow spectrum antibiotics), “by turning our attention to infections that make a large contribution to resistance evolution but are clinically mild, we may increase the success rate of alternative therapeutics development and decrease the selection pressure for resistance to current antibiotics.”
Waldetoft, KW, Brown SP. Alternative therapeutics for self-limiting infections-an indirect approach to the antibiotic resistance challenge. PLoS Biol. 2017 Dec 28;15(12):e2003533.
This article originally appeared on MPR