Hantaviruses: Underestimated Respiratory Viruses?

with antibiotics demonstrates that a single dose or 3 days of treatment at most is sufficient for most patients. As to the choice of antibiotic, evidence demonstrates equivalency, if not superiority, of a fluoroquinolone in the treatment of individuals with TD, compared with every other class of antibiotic [3–5]. Data also support the use of azithromycin in individuals for whom fluoroquinolones are contraindicated or who develop TD in areas of the world with a high rate of fluoroquinolone-resistant Campylobacterassociated TD, such as South and Southeast Asia [6]. The use of rifaximin is supported in areas of the world where Escherichia coli–associated diarrhea is common, such as Mexico [3]. Although the introduction of rifaximin provides an alternative antibiotic, there may be potential drawbacks with this agent. It is not recommended for treatment of individuals with diarrhea in whom there is mucosal invasion with a pathogen, such as Shigella species, Campylobacter species, or in some cases, Salmonella species [5, 7]. In addition, although it is felt that the risk of development of resistance to rifaximin may be low, a recent study indicates that resistance can develop during treatment [5]. There is also the theoretical risk that widespread use of rifaximin will further induce resistance. Finally, Dr. Connor [1] notes that the development of irritable bowel syndrome following TD is a potential reason for considering prophylaxis for most travelers. Although the reported incidence of irritable bowel syndrome at 6 months after TD ranges from 4% to 14% [8–10], the true incidence of this syndrome is not clear, and all contributing factors to the syndrome and its potential prevention have yet to be defined. The guidelines panel welcomes continued investigation into TD, one of the most common ailments of travelers. Nevertheless, until there is clear supporting evidence to change recommendations, the current Infectious Diseases Society of America guidelines on the management of TD should be followed, including attention to choice of food and beverage and, in the event of diarrhea, prompt self-treatment (hydration, symptom control, and short-course antibiotic treatment in selected patients). At present, chemoprophylaxis should be restricted to wellinformed travelers in whom the benefits clearly outweigh the risks.