Eukaryota; Alveolata; Apicomplexa; Coccidia; Eucoccidiorida; Eimeriorina; Calyptosporidae; Calyptospora (4).
Description and significance
Calyptospora funduli does not seem to cause diseases directly in humans(1). It does however cause disease to occur in killifish (1). C. funduli acts as a parasite on the fish by using an intermediate host to infect the killifish (1, 3). Killifish consume grass shrimp as their source of nutrients (1). The C. funduli infects the grass shrimp with sporozoites; therefore, when the killifish consumes the infected shrimp, the fish is then infected itself (1). The parasite's sporozoites can access to the fish's circulatory system through its hepatocytes and research shows that the sporozoites are present in the peripheral blood of the killifish four hours after ingesting the shrimp (1, 3). The sporozoites seek out the liver where they finally stay, and quickly replace much of the fish's liver cells (1, 3). With the already small liver almost completely consumed by the parasite, the fish begins to develop liver disease which eventually leads to the death of the fish (1, 3).
The genomic information for Calyptospora funduli is not yet known.
Cell structure, metabolism & life cycle
Calyptospora funduli is an apicomplexan parasite (3). It infects many atheriniform fishes on the eastern coasts of North America. It requires an intermediate host in order to complete its life cycle (3). It has a rather broad host specificity and infects a large range of hosts including all atheriniform members of the genus Fundulus (2). C. funduli does not develop in any perciform fishes due to some innate barriers (2). The parasite infects the intermediate host (many times the grass shrimp) and develops into infective sporozoites (3). The definitive host (in many cases the killifish) then ingests the intermediate host (3). The sporozoites enter the blood stream of the host through hepatocytes and travel through the peripheral blood supply and eventually reach the target organ -- the liver (3). There the sporozoites develop into oocysts and take over the hosts liver, causing liver disease and eventually death (3).
Ecology (including pathogenesis)
Calyptospora funduli is a parasite and therefore lives within its definitive ad intermediate hosts (1, 3). It does not like very low temperatures and parasitizes the killifish in the environment (1, 3). It causes disease in these fish by infecting their liver and overtaking the liver (1, 3). The killifish suffers liver disease and eventually the parasite wins, resulting in the death of the fish (1, 3). The parasite has a broad host specificity so the killifish is not the only fish parasitized by the organism, however it is the most common. Another example is the toadfish (5).
The ability of C. funduli to infect killifish is significantly diminished in response to cold temperatures (1). Research has shown that when the infected fish is kept in an environment with a temperature of 7 - 10 degrees Celcius for twenty days, there is a significant decrease in the intensity of the infection (1). Also, when the infected fish is immediately placed in an environment of 7 degrees Celsius, it has been observed that the immediate stages of the infection are gone in five days (1).
References 1. Couch, J., Fournie, J., Center for Marine and Estuarine Disease Research. "Pathobiology of marine and estuarine organisms". Advances in Fisheries Science. p. 121-122. 2. Fournie, J., Overstreet, R. "Host Specificity of Calyptospora funduli (Apicomplexa: Calyptosporidae) in Atheriniform Fishes". The Journal of Parasitology. 1993. Volume 79. No. 3. p. 720-727. 3. Fournie, J., Vogelbein, W., Overstreet, R., Hawkins, W. "Life Cycle of Calyptospora funduli (Apicomplexa: Calyptosporidae)". The Journal of Parasitology. 2000. Volume 86. No. 3. p. 501-505. 4. http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi 5. http://www.flmnh.ufl.edu/fish/Gallery/Descript/gulftoadfish/gulftoadfish.html