effective against this strain. We don’t think this strain is very widespread but we just don’t know yet because its discovery is so recent. There were specimens that had this virus that were from almost 20 years ago, but a new method of molecular genetic testing (called next-generation gene sequencing) allowed scientist to recognize the unique features of this virus and classify it as a new subtype.
HIV originated in Africa and spread to other parts of the world. Some scientists believe that HIV came into the human species from chimpanzees, yet HIV is very seldom found in wild chimpanzees. HIV-2 is found in a type of monkey called the Sooty mangabey, but it doesn’t cause disease in these monkeys. HIV doesn’t cause disease in most apes and monkeys because their bodies produce compounds which block infection by HIV.
These compounds are specialized proteins called restriction factors, and they can work in a variety of ways along with the immune system to fight HIV naturally. Humans also produce a variety of restriction factors which can seriously slow down the virus in our bodies and helps explain why HIV takes several years to progress to AIDS and cause death. Perhaps, by studying subtype L virus and people who are infected with that strain, we may discover new ways that our bodies can fight the virus through restriction factors or the immune system and possibly develop new treatments.
I’m sure we’ll be hearing more about subtype L HIV in the near future.
Dr. Crawford has over 25 years of experience in the treatment of HIV. While at Howard University School of Medicine, he worked in two HIV-specialty clinics at Howard University Hospital. He then did clinical research as a visiting scientist with the AIDS Clinical Trials Group (ACTG) at Johns Hopkins University School of Medicine. He served as the Assistant Chief of Public Health Research with the Military HIV Research Program where he managed research studies under the President’s Emergency Plan for AID Relief (PEPFAR) in four African countries.
He is currently working in the Division of AIDS in the National Institutes of Health. He has published research in the leading infectious diseases journals and serves on the Editorial Board of the journal AIDS. Any views and perspectives in his articles on blackdoctor.org are not representative of any agency or organization but a reflection of his personal views.