Researchers have identified a new HIV strain, the first discovered in nearly 20 years. In a study published Wednesday in the peer-reviewed Journal of Acquired Immune Deficiency Syndromes, a group of researchers at Abbott Laboratories, University of Missouri and the Presbyterian Mission Agency confirmed the first new strain of HIV since guidelines of classifying HIV strains were developed in 2000. The strain has been classified as subtype L in HIV-1 Group M. There are two main types of HIV: HIV-1 and HIV-2. Within HIV-1, there are multiple strains. Group M, which can be traced back to the Democratic Republic of Congo (DRC), is the strain that led in the global HIV epidemic. Isolated samples of the virus under subtype L were first spotted in the DRC in 1983 and again in 1990. A third sample was found in 2001, the basis of this study; however, researchers were unable to sequence, or identify, the genome to designate it as a subtype of HIV until this year. "Identifying new viruses such as