A long-term follow-up analysis of participants in the Step Study, an international HIV-vaccine trial, has confirmed that certain subgroups of male study participants were at higher risk of becoming infected after receiving the experimental vaccine compared to those who received a placebo.

Cancer is one of the most common causes of death in humans.

A clinical trial testing a candidate HIV vaccine known as the STEP study was halted in September 2007 after interim analysis indicated that the vaccine did not work.

Adenoviruses can cause respiratory, eye, and intestinal tract infections, and, like other viruses, must hijack the cellular machinery of infected organisms in order to produce proteins and their own viral spawn.

They have been around since the dawn of time and are a model of evolutionary success: viruses.