Hepatitis B is a viral disease that targets the liver and affects approximately 257 million people worldwide. It is caused by the hepatitis B virus (HBV), which is passed from person to person through blood or other body fluids. In a recent discovery, an international team of researchers from Germany, Brazil and Belgium found that HBV originated in nonhuman primates; more precisely, they discovered that the virus originally emerged in the African ancestors of South American monkeys. Until now, there had been no clear evidence of its evolutionary origin. As hepatitis B is not an airborne disease, it must have emerged in African monkeys, who then traveled to South America via islands in the Atlantic Ocean at a time when the coast of West Africa was much closer to South America than it is today. This conclusion is in line with previous research findings which suggest that the monkeys now found in South America have African ancestry.
“The precise details of HBV’s transmission to hominids – such as when, where and how it was transmitted – remain a mystery, though it was likely transmitted by a monkey infected with the virus,” says the study’s lead researcher, Prof. Dr. Jan Felix Drexler, who heads the Virus Epidemiology Group at Charité’s Institute of Virology. “What is certain, however, is that the virus we isolated in Brazilian capuchin monkeys is similar to human HBV and that it uses the same surface proteins to infect human liver cells,” explains Prof. Drexler. The new virus, which the researchers named capuchin monkey hepatitis B virus (CMHBV), is only the second HBV species to have been isolated in nonhuman primates; the first one was discovered in woolly monkeys in 1998.
“So far, effective treatments for chronic hepatitis B have been few and far between,” says Prof. Dr. Dieter Glebe, Director of the JLU’s National Reference Center for Hepatitis B and D Viruses. He adds: “We would like to use our insights into the CMHBV to develop new models for use in preclinical drug development research.”