While collecting mosquitoes in an attempt to look for a bird-specific malaria two years ago, scientist Ellen Martinsen from The University of Vermont discovered a DNA profile from parasites located in the insects that she couldn't identify. Now, in her current study, she reveals that parasite as Plasmodium odocoilei, a malaria parasite that infects white-tailed deer.
The finding marks the first-ever malaria parasite known to live in a deer species, as well as the only native malaria parasite that has ever been discovered in a mammal from North or South America. Martinsen and her team believe that the parasite could infect up to 25 percent of white-tailed deer along the East Coast of the United States.
"You never know what you're going to find when you're out in nature - and you look," Martinsen said in a press release. "It's a parasite that has been hidden in the most iconic game animal in the United States. I just stumbled across it."
The deer malaria is apparently widespread, although Martinsen says that it is "cryptic" due to the fact that the parasites are present in such low levels in many of the infected deer. Using sensitive molecular techniques, the team was able to better understand the genetics of the parasite and confirm the high prevalence of the disease in sites ranging from New York to West Virginia.
Not only does the discovery change our current understanding of malaria's distribution and history in mammals by revealing a divergence between the two forms of malaria present in white-tailed deer, it allows scientists to date the split between the two forms and points to malaria as a disease native to the Americas that resided there for millions of years.
"Malaria is a top parasitic disease in humans and wildlife," Martinsen said. "It's important that we gain a better understanding of its diversity and distribution not just across humans but across other species too."
The findings were published in the Feb. 5 issue of Science Advances.
