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BackgroundRecent developments related to a safe and effective nonabsorbable antibiotic, rifaximin, and identification of postinfectious irritable bowel syndrome as a frequent sequela call for a need to reconsider the value of primary prevention of traveler’s diarrhea (TD) with antibiotics.MethodsRandomized, placebo-controlled, double-blind studies evaluating the effectiveness and safety of rifaximin or a fluoroquinolone chemoprophylaxis against TD were pooled using a random effects model and assessed for heterogeneity.ResultsThe nine studies (four rifaximin and five fluoroquinolone) included resulted in pooled relative risk estimates of 0.33 (95% CI = 0.24–0.45, I2 = 3.1%) and 0.12 (95% CI = 0.07–0.20, I2 =0.0%), respectively. Similar rates of treatment emergent adverse events were found between antibiotic and placebo groups.ConclusionsThis meta-analysis supports the effectiveness of antibiotics in preventing TD. However, further studies that include prevention of secondary chronic health outcomes among travelers to different geographic regions, and a formal risk-benefit analysis for antibiotic chemoprophylaxis, are needed.

Alternative sterilization methods including ethylene oxide, gas plasma, and gamma-radiation in an inert environment were implemented in the late 1990s, to limit oxidative degradation of ultrahigh molecular weight polyethylene (PE). There was also a simultaneous transition to PE resins that did not contain calcium stearate. Shelf storage duration of PE inserts following gamma-irradiation in air has been correlated to poor clinical performance and increased wear. This study aimed to determine how sterilization method and resin type influenced degradation of PE after 4 years of real-time shelf aging. It was hypothesized that gamma-irradiation and stearate containing resins would incur significantly more degradation than nonradiated, stearate-free resins. Gamma-irradiated PE samples in air and nitrogen had a significantly increased density and oxidation index, compared to nonirradiated PE after 4 years of shelf aging. Alternative sterilization methods such as ethylene oxide and gas plasma appeared to have significantly less oxidation regardless of PE resin type. A partial correlation demonstrated that density and oxidation index were not correlated (r(2) = 0.079) when examining the influence of sterilization method. The data supported that after 4 years of real-time shelf aging, the type of sterilization method had a larger influence on PE degradation than resin type.