Scientists at Harvard Medical School and Boston University Chobanian & Avedisian School of Medicine have mapped a critical component of the Nipah virus, a highly lethal bat-borne pathogen that has caused outbreaks in humans almost every year since it was identified in 1999.
- By HMS AND BU COMMUNICATIONS
The advance, described Jan. 20 in Cell, brings scientists a step closer to developing much-needed medicines. Currently, there are no vaccines to prevent or mitigate infection with the Nipah virus and no effective treatments for the disease other than supportive care.
The virus, harbored by fruit bats, can be transmitted to pigs and to humans. It can also infect people through contaminated food and can travel directly from person to person via droplets released when coughing. The World Health Organization has declared Nipah virus a priority pathogen, a designation given to organisms that can cause serious outbreaks and require urgent research to inform prevention and treatment strategies.
Nipah virus has the potential to ignite a pandemic, researchers say, because it can spread via airborne droplets and respiratory secretions. Additionally, the researchers note, evidence hints that some infected people who develop milder, nonspecific symptoms may still transmit the virus.
In severe cases, the infection can cause serious respiratory illness and encephalitis, a form of brain inflammation that can lead to devastating neurologic deficits and death. The virus kills between 40 and 75 percent of those infected, according to estimates from the Centers for Disease Control and Prevention. By comparison, Ebola virus kills between 25 and 90 percent of those infected in past outbreaks, with an average death rate of 50 percent.
In the new study, researchers homed in on a part of the viral machinery called the viral polymerase complex, a group of proteins the virus uses to copy its genetic material, spread, and infect cells. The work provides a detailed three-dimensional picture of the virus's polymerase and its key features. Understanding the structure and behavior of this critical piece of the viral machinery illuminates how the pathogen multiplies inside its hosts.
