Scientists have discovered that an old anti-malaria drug is effective against two fatal viruses that recently jumped from animals to humans.
The closely related viruses, Nipah and Hendra, live in the fruit bats sometimes called flying foxes and are believed to infect animals that eat fruit contaminated with the bats’ urine or saliva.
Nipah was discovered in 1999, when it was blamed for the deaths of 106 people in Malaysia and Singapore, mostly farm or slaughterhouse workers who got it from pigs.
Since 2001, Nipah has killed more than 100 in Bangladesh and India. The early deaths were from brain infections, but in 2004 it also took on a respiratory form transmitted from person to person. Each small outbreak had a different death rate, but most were well over 50%.
Hendra was discovered in 1994 in Australia, where it has killed dozens of horses and two of four humans known to have been infected by horses.
Until recently, there was no known treatment. But in the last month, two teams of scientists—one at Cornell’s medical school in New York and one in France—separately discovered that chloroquine, a malaria drug invented 50 years ago, prevents both viruses from reproducing.
Chloroquine has a long safety record and, in laboratory tests, appears to work at doses even lower than those used to prevent malaria.
It has not yet been tested against Nipah or Hendra in humans but presumably will be during the next outbreak, scientists said.
©2009/THE NEW YORK TIMES