Galapagos penguins(Spheniscus mendiculus) harbour malaria threat. Penguins and malaria are not 2 organisms you would normally associate with each other, yet biologists have found the malaria parasite in an endangered species of the black-and-white waddlers.Iris Levin of the University of Missouri at St. Louis and her colleagues took blood samples from 362 Galapagos penguins already listed as being threatened with extinction on 9 islands in the Galapagos archipelago.All of the birds appeared healthy, but the tests revealed that 19 of the penguins, 5 percent, carried the _Plasmodium_ parasite, which causes malaria. The infected birds were spread across the archipelago, suggesting the parasite is not restricted to one small colony of penguins. Galapagos penguins move around the islands, so the parasite is likely to spread further, say the researchers."_Plasmodium_ in Galapagos penguins is potentially disastrous for this species," says Bruce Hofkin, a parasitologist at the University of NewMexico in Albuquerque, who was not involved in the study. "Most penguin species are very susceptible to Plasmodium and avian malaria is a real problem in zoos, where it is a major problems in penguin exhibits."Dangerous to visitor". The mosquitoes that can carry Plasmodium arrived on the archipelago in the 1980s, presumably on incoming boats or flights. Researchers have been concerned that the parasite may take hold but had not found any evidence of it until now.Levin says that although the birds were healthy, there is still cause for concern. The biologists point out that Plasmodium has decimated wild bird populations in Hawaii; that the strain they found is closely related to a strain that causes avian malaria in captive penguins; and that the Galapagos penguins are unlikely to have encountered the malaria parasite before, making them vulnerable to it.One other factor concerns them at least as much as all of the above is the El Nino phenomenon. The reduction in fish numbers during El Nino seasons can slash the penguin population in the Galapagos by up to 80 percent. The researchers fear that this could trigger malaria signs and deaths in infected birds.Although the Galapagos penguin population has been on the rise since the major El Nino event of 1997-1998, when the penguins are thought to have been free of Plasmodium (Marine Ornithology, vol 29, p 43), it is still only half of what it was before.Other research has suggested that stress can increase the death rate among birds that have malaria. And computer models suggest El Nino events may become slightly stronger with climate change. Put all this together, say the researchers, and you get the picture of the Galapagos penguins under attack from all sides.Journal reference: Biological Conservation (DOI: 10.1016/j.biocon.2009.06.017)[Byline: Catherine Brahic] Penguin malaria, caused by Plasmodium relictum & P. elongatum, is characterized by the exoerythrocytic (EE) forms in many different tissues and overall low-grade parasitemia. Either organism is capable of causing rapidly fatal disease with barely detectable parasitemias-- the EE stages are the key to understanding the pathology (Fleischman et al. 1968. J Am Vet Med Assoc 153:928-935).Chloroquine and primaquine can be used to effectively treat infected birds (Stoskopf and Beier 1979. J Am Vet Med Assoc 175:944-947). The epidemiology of infection and zoo management issues for Black-footed penguins at the Baltimore Zoo is well documented and has been applied to penguin malaria since the 1970s (Beier and Stoskopf 1980. J Zoo An Med 11:99-105).The Plasmodium protozoan parasite has been detected in temperate and sub-Antarctic species, including African S. demersus, Yellow-eyed Megadyptes antipodes, Rockhopper Eudyptes chrysocome and Chinstrap Pygoscelis Antarctica Penguins (Clarke and Kerry 1993).While this article does not tell us how they tested for the malarial organism, it is likely that a PCR was used. While it is possible to diagnoses the organism on blood smears, this may have been a cumbersome technique for the number of animals that may have been sampled._Culex_ sp and _Aedes_ sp are likely the vectors of the organism, but this article is not specific on the disease vector. - Mod.TG][A map showing the location of the Galapagos Islands is available at:<http://www.worldatlas.com/webimage/countrys/samerica/galap.htm> - CopyEd.EJP][see also:2000----Malaria, zoo penguins - UK 20000621.10131999----Malaria, zoo penguins - UK (03) 19991017.1847 Malaria, zoo penguins - UK (02) 19991011.1815 Malaria, zoo penguins - UK 19991009.1805]
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