Zimmerman's colleague, David Serre, PhD, of the Cleveland Clinic's Genomic Medicine Institute, said that while there is not yet enough evidence to conclude that the P. vivax parasite is gaining virulence, "we think the genetic mechanisms we have uncovered could dramatically change our understanding of this very important form of malaria that doesn't get as much attention as falciparum malaria, even though it causes severe disease and may be more deadly than many think."
Also, vivax malaria is in one respect more dangerous than falciparum malaria: the P. vivax parasite has the ability to "hide" in the liver and re-emerge multiple times in the bloodstream to cause relapse infections.
Kevin Baird, PhD, an expert in vivax malaria at the Eijkman-Oxford Clinical Research Unit in Indonesia, said the "expanding reports of vivax malaria in Duffy-negative individuals are alarming." But Baird, who was leading discussions at the ASTMH Annual Meeting on improving vivax malaria diagnostics and treatment, said it remains to be seen whether "this is an emerging problem or a low-probability event that has always been around." He also noted that research identifying infections in Duffy-negative individuals indicates that, overall, people who lack the protein still seem less likely to get vivax malaria, even if they may not be fully protected.
In Madagascar, a Surge in Duffy-Negative Infections
Zimmerman and his colleagues looked for biological mechanisms that might explain "Duffy-negative infections" by sequencing the genome of several P. vivax parasites, including parasites gathered in Madagascar. Madagascar has been of particular interest, they said, because infections in Duffy-negative individuals have been occurring there at a comparatively high rate.
In the study published today, they report finding something that had not been seen before in P. vivax parasites: two copies of the gene th
|Contact: Preeti Singh