Traditionally, the Microsporidia were primarily studied in insects and fish. There were only a few human cases of microsporidiosis reported until the advent of AIDS, when the number of human microsporidian infections dramatically increased and the importance of these new pathogens to medicine became evident. Over a dozen different kinds of microsporidia infecting humans have been reported. While some of these infections were identified in new genera (Enterocytozoon, Vittaforma), there were also infections identified from established genera such as Pleistophora and Encephalitozoon. The genus Pleistophora, originally erected for a species described from fish muscle, and the genus Encephalitozoon, originally described from disseminated infection in rabbits, suggested a link between human infections and animals. In the 1980's, three Pleistophora sp. infections were described from human skeletal muscle without life cycles presented. Subsequently, the genus Trachipleistophora was established for a human-infecting microsporidium with developmental differences from species of the genus Pleistophora. Thus, the existence of a true Pleistophora sp. or spp. in humans was put into question. We have demonstrated the life-cycle stages of the original Pleistophora sp. infection from human muscle, confirming the existence of a true Pleistophora species in humans, P. ronneafiei Cali et Takvorian, 2003, the first demonstrated in a mammalian host. Another human infection, caused by a parasite from invertebrates, was Brachiola algerae Lowman, Takvorian et Cali, 2000. The developmental stages of this human muscle-infecting microsporidium demonstrate morphologically what we have also confirmed by molecular means, that B. algerae, the mosquito parasite, is the causative agent of this human skeletal muscle infection. B. algerae had previously been demonstrated in humans but only in surface infections, skin and eye. The diagnostic features of B. algerae and P. ronneafiei infections in human skeletal muscle are presented. While Encephalitozoon cuniculi has been known as both an animal (mammal) and human parasite, the idea of human microsporidial infections derived from cold-blooded vertebrates and invertebrates has only been suggested by microsporidian phylogeny based on small subunit ribosomal DNA sequences but has not been appreciated. The morphological data presented here demonstrate these relationships. Additionally, water, as a link that connects microsporidial spores in the environment to potential host organisms, is diagrammatically presented.

Department of Biologic Sciences Rutgers University Newark New Jersey 07102 USA

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Avery SW, Anthony DW. Ultrastructural study of early development of Nosema algerae in Anopheles albimanus. J. Invertebr. Pathol. 1983;42:87–95. PubMed

Baker MD, Vossbrinck CR, Didier ES, Maddox JV, Shadduck JA. Small subunit ribosomal DNA phylogeny of various microsporidia with emphasis on AIDS related forms. J. Eukaryot. Microbiol. 1995;42:564–570. PubMed

Becnel JJ, Andreadis TG. Microsporidia in insects. In: Wittner M, Weiss LM, editors. The Microsporidia and Microsporidiosis. Washington, D.C.: ASM Press; 1999. pp. 447–501.

Cali A. Morphogenesis in the genus Nosema. Proc. IV Intl. Colloq. Insect Pathol., College Park, MD. 1970:431–438.

Cali A. General microsporidian features and recent findings on AIDS isolates. J. Protozool. 1991;38:625–630. PubMed

Cali A, Coyle C, Takvorian PM, Wittner M, Rhodes LV, Brown D, Naktin J, Yound E, Colasant G, Weiss LM. Preliminary evidence for Brachiola algerae as the etiology of a case of myositis. VIII International Workshops on Opportunistic Protists (IWOP-8) and International Conference on Anaerobic Protists (ICAP); July, 2003; Hilo, HI, U.S.. 2003.

Cali A, Owen RL. Microsporidiosis. In: Balows A, et al., editors. Laboratory Diagnosis of Infectious Diseases, Principles and Practice. New York: Springer-Verlag; 1988. pp. 929–950.

Cali A, Takvorian PM. Developmental morphology and life cycles of the Microsporidia. In: Wittner M, Weiss LM, editors. The Microsporidia and Microsporidiosis. Washington, D.C.: ASM Press; 1999. pp. 85–128.

Cali A, Takvorian PM. Ultrastructure and development of Pleistophora ronneafiei n. sp., a microsporidium (Protista) in the skeletal muscle of an immune-compromised individual. J. Eukaryot. Microbiol. 2003;50:77–85. PubMed

Cali A, Takvorian PM. The Microsporidia: pathology in man and occurrence in nature. S. E. Asian J. Trop. Med. Public Health. 2004;35 Suppl:58–64.

Cali A, Takvorian PM, Lewin S, Rendel M, Sian CS, Wittner M, Tanowitz HB, Keohane E, Weiss LM. Brachiola vesicularum, n. g., n. sp., a new microsporidium associated with AIDS and myositis. J. Eukaryot. Microbiol. 1998;45:240–251. PubMed

Cali A, Weiss LM, Takvorian PM. An analysis of the microsporidial genus Brachiola, with comparisons of human and insect isolates of B. algerae. J. Eukaryot. Microbiol. 2004;51:678–685. PubMed PMC

Canning EU, Nicholas JP. Genus Pleistophora (Phylum Microspora): redescription of the type species, Pleistophora typicalis Gurley, 1893 and ultrastructural characterization of the genus. J. Fish Dis. 1980;3:317–338.

Canning EU, Lom J. The Microsporidia of Vertebrates. London: Academic Press; 1986. p. 289.

Chupp GL, Alroy J, Adelman LS, Breen JC, Skolnik PR. Myositis due to Pleistophora (Microsporidia) in a patient with AIDS. Clin. Infect. Dis. 1993;16:15–21. PubMed

Coyle CM, Weiss LM, Rhodes LV, Cali A, Takvorian PM, Brown DF, Visvesvara GS, Xiao LH, Naktin J, Young E, Gareca M, Colasante G, Wittner M. Fatal myositis due to the microsporidian Brachiola algerae, a mosquito pathogen. N. Engl. J. Med. 2004;351:42–47. PubMed PMC

Dengjel B, Zahler M, Hermanns W, Heinritzi K, Spillmann T, Thomschke A, Loscher T, Gothe R, Rinder H. Zoonotic potential of Enterocytozoon bieneusi. J. Clin. Microbiol. 2001;39:4495–4499. PubMed PMC

Desportes I, Le Charpentier Y, Galian A, Bernard F, Cochand-Priollet B, Lavergne A, Ravisse F, Modigliani R. Occurrence of a new microsporidian: Enterocytozoon bieneusi n. g., n. sp., in the enterocytes of a human patient with AIDS. J. Protozool. 1985;32 250–245. PubMed

Dowd SE, Gerba CP, Pepper IL. Confirmation of the human-pathogenic microsporidia Enterocytozoon bieneusi, Encephalitozoon intestinalis, and Vittaforma corneae in water. Appl. Environ. Microbiol. 1998;64:3332–3335. PubMed PMC

Enriquez FJ, Taren D, Cruzlopez A, Muramoto M, Palting JD, Cruz P. Prevalence of intestinal encephalitozoonosis in Mexico. Clin. Infect. Dis. 1998;26:1227–1229. PubMed

Fournier SD, Liguory SO, Gaussin F, Santillana-Hayat M, Sarfati C, Molina J-M, Derouin F. Detection of microsporidia, cryptosporidia and giardia in swimming pools: a one-year prospective study. FEMS Immunol. Med. Microbiol. 2002;33:209–213. PubMed

Grau A, Valls ME, Williams JE, Ellis DS, Muntane MJ, Nadal C. Miositis por Pleistophora en un paciente con sida. Med. Clin. (Barc.) 1996;107:779–781. PubMed

Gurley R. On the classification of the myxosporidia, a group of protozoan parasites infecting fishes. Bull. U.S. Fish. Comm. 1893;11:407–420.

Hollister WS, Canning EU, Weidner E, Field AS, Kench J, Marriott DJ. Development and ultrastructure of Trachipleistophora hominis n.g., n.sp. after in vitro isolation from an AIDS patient and inoculation into athymic mice. Parasitology. 1996;112:143–154. PubMed

Koudela B, Visvesvara GS, Moura H, Vávra J. The human isolate of Brachiola algerae (Phylum Microspora): development in SCID mice and description of its fine structure features. Parasitology. 2001;123:153–162. PubMed

Lainson R, Garnham PCC, Killick-Kendrick R, Bird RG. Nosematosis, a microsporidial infection of rodents and other animals, including man. Brit. Med. J. 1964;2:470–472. PubMed PMC

Ledford DK, Overman MD, Gonzalvo A, Cali A, Mester SW, Lockey RF. Microsporidiosis myositis in a patient with the acquired immunodeficiency syndrome. Ann. Intern. Med. 1985;102:628–630. PubMed

Levaditi C, Nicolau S, Schoen R. L’agent étiologique de l’encéphalite épizootique du lapin (Encephalitozoon cuniculi) C. R. Soc. Biol. Paris. 1923;89:984–986.

Lowman PM, Takvorian PM, Cali A. The effects of elevated temperature and various time-temperature combinations on the development of Brachiola (Nosema) algerae n. comb. in mammalian cell culture. J. Eukaryot. Microbiol. 2000;47:221–234. PubMed

Macher AM, Neafie R, Angritt P, Tuur SM, Nelson RP, Cali A. AIDS. Case for diagnosis series, 1988. Military Med. 1988;153:M41–M48. PubMed

Orenstein JM, Gaetz HP, Yachnis AT, Frankel SS, Mertens RB, Didier ES. Disseminated microsporidiosis in AIDS – are any organs spared. AIDS. 1997;11:385–386. PubMed

Strano AJ, Cali A, Neafie RC. Pathology of Tropical and Extraordinary Diseases – An Atlas. Vol. 1. Washington, D.C.: Armed Forces Institute of Pathology; 1976. Microsporidiosis; pp. 336–339.

Sulaiman IM, Fayer R, Lal AA, Trout JM, Schaefer FW, Xiao LH. Molecular characterization of microsporidia indicates that wild mammals harbor host-adapted Enterocytozoon spp. as well as human-pathogenic Enterocytozoon bieneusi. Appl. Environ. Microbiol. 2003;69:4495–4501. PubMed PMC

Terada S, Reddy K, Jeffers LJ, Cali A, Schiff ER. Microsporidan hepatitis in the acquired immunodeficiency syndrome. Ann. Intern. Med. 1987;107:61–62. PubMed

Thurston-Enriquez JA, Watt P, Dowd SE, Enriquez R, Pepper IL, Gerba CP. Detection of protozoan parasites and microsporidia in irrigation waters used for crop production. J. Food Prot. 2002;65:378–382. PubMed

Vavra J, Undeen AH. Nosema algerae n. sp. (Cnidospora, Microsporida) a pathogen in a laboratory colony of Anopheles stephensi Liston (Diptera, Culicidae) J. Protozool. 1970;17:240–249. PubMed

Vávra J, Larsson JIR. Structure of the Microsporidia. In: Wittner M, Weiss LM, editors. The Microsporidia and Microsporidiosis. Washington, D.C.: ASM Press; 1999. pp. 7–84.

Visvesvara GS, Belloso M, Moura H, Da Silva A, Moura I, Leitch G, Schwartz DA, Chevez-Barrios P, Wallace S, Pieniazek NJ, Goosey J. Isolation of Nosema algerae from the cornea of an immunocompetent patient. J. Eukaryot. Microbiol. 1999;46:10S. PubMed

Weiss LM, Vossbrinck CR. Molecular biology, molecular phylogeny, and molecular diagnostic approaches to the Microsporidia. In: Wittner M, Weiss LM, editors. The Microsporidia and Microsporidiosis. Washington, D.C.: ASM Press; 1999. pp. 85–128.

Weiser J. On the taxonomic position of the genus Encephalitozoon Levaditi, Nicolau and Schoen, 1923 (Protozoa: Microsporidia) Parasitology. 1964;54:749–751. PubMed

Wittner M, Weiss LM. The Microsporidia and Microsporidiosis. 1 Ed. Washington, D.C.: American Society for Microbiology Press; 1999. p. 553.