BETHESDA, Md., June 10 (UPI) -- U.S. National Institutes of Health scientists say they've identified two previously unknown steps in the spread of the malaria parasite in the bloodstream.
The NIH researchers said they also were able to interfere with one of the steps, raising the possibility that new drug treatments might be developed to combat the disease.
Malaria is caused by a single-celled parasite that is transmitted to humans through the bite of an infected mosquito, scientists said.
Joshua Zimmerberg, the study's lead author, said a malaria parasite reproduces inside a sac within a red blood cell, filling the sac until the new parasites burst out of their host cell. Many researchers say the pressure of the growing parasites inside the sac increases until it bursts.
But Zimmerberg said the study uncovered a more complex process. Several minutes before rupturing, the parasite-filled sac swells and the remainder of the cell shrinks, he said. Moreover, seconds before the infected cell bursts, the cell membrane turns porous, like a leaky plastic bag.
"It is not the simple explosion people thought it was," Zimmerberg said. "It appears to be more like a ballet -- an elegantly choreographed, regulated process."
The scientists said they also discovered they could, in effect, seal the membrane of an infected blood cell with a surface-acting compound, halting the release of the parasites.
"Identifying new stages in the release of parasites provides new leads in the search for anti-malaria drugs," Zimmerberg said.
