Bird Malaria, Human Malaria
Did the Dangerous Plasmodium falciparum Come From Birds?
Molecular studies have suggested that Plasmodium falciparum, scourge of humanity, is related to Plasmodium parasites of birds.
Malaria, caused by the blood parasite Plasmodium spp., infects nearly 500 million people in the world today—nearly one and a half million people live in parts of the world where malaria is endemic. Millions die every year.
Of the four species of Plasmodium that infect humans, P. falciparum is the most dangerous, causing so called malignant tertian, or falciparum, malaria. Those who read blood films looking for malaria parasites know that this species is different—the classic banana shaped gametocytes of P. falciparum are unlike anything seen with the other plasmodia that cause malaria in humans.
It has been proposed that, while the other three species probably made the leap to humans from other primates, P. falciparum may have come from birds—and this may explain why the disease is so much more virulent than other forms of human malaria. The human immune system would presumably be somewhat equipped to deal with a primate parasite, whereas an avian one would be much more foreign to it.
Molecular and other studies confirm that P. falciparum is most closely related to P. gallinaceum and P. lophurae, plasmodia of birds. Thus, though we don’t know for sure, scientific evidence suggests that we may have birds to thank for “the greatest killer of humanity in tropical zones of the world today” (Roberts and Janovy, p. 148).
Read more about malaria:
Sources:
Desowitz, Robert S. The Malaria Capers. New York: W. W. Norton and Company, 1991.
Roberts, Larry S. and John Janovy Jr. Foundations of Parasitology 6th Ed. Boston: McGraw Hill, 2000.
