|Avian malaria in bird red blood cells. This Hawaiian strain of avian malaria arrived after mosquitoes were introduced to the Hawaiian Islands and is devastating to most Hawaiian native birds. In most cases a simple infection is fatal. CCEG scientists study the genetics of the malaria parasite, mosquito vector, and bird hosts in order to understand the dynamics of the infection and how we might be able to control it.
Photo credit: Rob Fleischer
|The amakihi is one of only a few of the dozens of Hawaiian honeycreeper species that can survive infection with introduced avian malaria. CCEG scientists have been trying to understand why this species is different from most of its relatives. How has it recovered much of its low elevation range, and what genes may be involved in resistance to the malaria
Photo Credit: Jack Jeffreys
Disease diagnosis and dynamics: Wildlife diseases are important to study because they may cause significant decreases in survival and reproduction in both captive and wild animal populations and thus be of conservation concern. Also, wildlife diseases may serve as sources of diseases that jump into human populations and become human health risks.
Molecular genetic methods can be very useful in diagnosing diseases, and for understanding the dynamics of disease in natural populations. CCEG scientists apply many of these methods in their wildlife disease projects, most of which involve collaboration with other Smithsonian scientists--in particular members of the Departments of Pathology and Veterinary Medicine, and Migratory Bird Center at the Zoo.
CCEG has developed diagnostic methods for identifying and determining prevalence of blood parasites such as malaria in birds, Hepatozoon in carnivores, bacteria in marsupials, and viruses such as avian influenza. CCEG scientists have also been studying the host genetically-based immune responses to bacteria such as Mycoplasma in house finches and generalized pathogens in elephants. CCEG and the Zoo's Pathology and Animal Health Department scientists have recently begun a major project to study how often parasites transfer between wild and collection birds at the Zoo, if these parasites cause disease, and whether host generalists parasites are most likely to make the shift.
A major, long-term project involves disease impacts in endangered native Hawaiian birds. The study assesses genetic interactions among native and introduced Hawaiian birds (the diseases’ hosts), introduced mosquito vectors (Culex quinquefasciatus), and an introduced and variably virulent strain of avian malaria (Plasmodium relictum).