Microsoft researchers are using the same principles they employed to build email spam filters to help find an HIV vaccine, Technet reports. One of the greatest challenges to fighting HIV is that it is constantly mutating. This makes it difficult for researchers to accurately analyze the virus, which they must do to develop vaccines that target its weak points. Now a team at Microsoft Research is using a Microsoft Computational Biology Tool, PhyloD, to help doctors collecting data in the field. PhyloD, which was built on the same principles used to build spam filters for Hotmail, Outlook and Exchange, is able to complete complex analyses to show how individual immune systems respond to mutations of the virus. The team has now discovered roughly six times as many possible attack points than had previously been identified.