The big news out of the International AIDS Conference in Mexico City this week is troubling. The Centers for Disease Control and Prevention (CDC) released its updated estimates of new HIV infections in the U.S. for 2006, revealing a total 40 percent higher than previously thought. For a study published in the August 6th edition of the Journal of the American Medical Association, researchers utilized new and more precise methods to find that about 56,300 adults and adolescents were newly infected with HIV in 2006. Their previous estimate was close to 40,000.

The CDC also used the new methods to back-calculate historical trends in HIV infections. They found that HIV infections increased sharply after 1977, the first year of data, peaking at about 130,000 per year in 1984 and 1985. Infections then began to decline, bottoming out at about 49,000 infections per year in the early 1990s. Incidents jumped again to about 58,000 in the late 1990s and have remained steady at around 55,000 each year since.

When interviewed at the conference, Dr. Kevin Fenton, M.D., Ph.D., director of the CDC's National Center for HIV/AIDS, Viral Hepatitis, STD and TB Prevention, called these numbers a "wake-up call" and indicated that Americans need to step-up prevention measures.