Are Resistance Rates Rising or Holding Fairly Stable?

The usual rule in infectious diseases is that the more heavily a family of antimicrobial agents is used, the more prevalent resistance to those agents becomes. This precedent has inspired concern that rates of resistance to antiretrovirals will soar now that these drugs are in widespread use all over the world. A new study provides some reassurance.

Researchers estimated rates of resistance in a large cohort of HIV-infected individuals in Switzerland who have been followed since triple-drug treatment became the standard of care there. They used a novel methodology that combined actual resistance data from patients who underwent genotype testing with a series of assumptions to estimate resistance rates among patients who did not undergo such …