Working as part of an international team in the United States and West Africa, a researcher at The Scripps Research Institute (TSRI) has published new findings showing the ancient roots of the deadly Lassa virus, a relative of Ebola virus, and how Lassa virus has changed over time. “This gives us a clear view of how the virus is evolving, which is important to know as we develop vaccines and therapies,” said TSRI biologist Dr. Kristian G. Andersen, a lead author of the new study. At least 5,000 people die each year from Lassa fever. The virus is spread through contact with urine and droppings from infected Mastomys natalensis rodents (sometimes called “multimammate rats” or “multimammate mice” because of the female’s multiple and prominent mammary glands), which are a natural “reservoir” of the virus, and the disease can spread from human to human. In the new study, published as the cover story of the August 13, 2013 issue of the prestigious journal Cell, the international research team used a technique called next-generation sequencing to analyze genomes of Lassa virus samples taken from wild Mastomys natalensis and human patients in Nigeria and Sierra Leone. —whose senior members included Dr. Pardis Sabeti and Dr. Joshua Levin of Harvard University and the Broad Institute, Dr. Robert F. Garry of Tulane University and Dr. Christian Happi of Nigeria’s Irrua Specialist Teaching Hospital and Sierra Leone’s Kenema Government Hospita. The article is titled “Clinical Sequencing Uncovers Origins and Evolution of Lassa Virus.” The genomic data showed that far-flung strains of Lassa virus share a common ancestor that can be traced back more than 1,000 years to an area today known as Nigeria. This surprised the researchers, as Lassa fever was first described in Nigeria only in 1969. “The virus has very ancient roots,” said Dr. Andersen.Login Or Register To Read Full Story