While the World Health Organization recently recommended beginning HIV treatment once CD4s hit 500 or below, researchers from Johns Hopkins University have raised doubts of both the feasibility and the ethics of such a treatment expansion, considering the health care disparities between first and third world nations. Publishing in the journal Clinical Infectious Diseases, the scientists acknowledge that research clearly shows that early use of antiretrovirals (ARVs) benefits both HIV prevention efforts and people living with the virus. However, they argue that because the ARVs available at this time in resource-poor settings are often more outdated drugs, there are increased risks of side effects and toxicity weighing against the potential therapeutic benefits of early therapy. In addition, less effective therapies and inadequate or nonexistent laboratory monitoring may lead people to develop drug resistance, thus potentially limiting future treatment options.