Working independently, two research teams funded by the National Institute of Allergy and Infectious Diseases (NIAID), part of the National Institutes of Health (NIH), have identified how Nipah and Hendra viruses, closely related viruses first identified in the mid-1990s, gain entry into human and animal cells.
Nipah and Hendra are emerging viruses that cause serious respiratory and neurological disease. People can get these deadly viruses from animals. Beginning in 1994, public health officials have recognized disease outbreaks in Malaysia, Singapore, Bangladesh and Australia.
Both viruses use a protein essential to embryonic development to enter cells and begin their often-fatal attack, report researchers at the University of California, Los Angeles (UCLA) and the Uniformed Services University of the Health Sciences (USUHS) in Bethesda, Maryland.
The UCLA team, headed by Benhur Lee, M.D., describes its findings in a Nature paper posted online on July 6. The report by the USUHS researchers, led by Christopher Broder, Ph.D., is appearing online the week of July 4 in the Proceedings of the National Academy of Sciences.
The first reported outbreak of Nipah virus occurred in 1998-1999 in Malaysia, sickening 265 people and killing 105, according to the World Health Organization. This outbreak, which in this case spread from pigs to humans, was contained by culling more than a million pigs. Hendra virus, so far less of a threat to human health, was first identified in 1994 in Australia when it spread from horses to humans.
In addition to our concern about Nipah and Hendra viruses as emerging global health and economic threats, we worry about their potential use as bioterror agents, says Anthony S. Fauci, M.D., director of NIAID. This work, funded through our biodefense research program, is a major step towards developing countermeasures to prevent and treat Nipah and Hendra infection.
Using different methods, both teams identified a specific cell surface receptor, Ephrin-B2, as the doorway used by Nipah and Hendra viruses to get inside cells. This receptor is found on cells in the central nervous system and those lining blood vessels. It is crucial for the normal development of the nervous system and the growth of blood vessels in human and other animal embryos. Ephrin-B2 is found in humans, horses, pigs, bats and other mammals, which explains the unusually broad range of species susceptible to Nipah and Hendra virus infection.
Message posted by: Rashmi Nemade