Centers for Disease Control/Division of Parasitic Diseases and Malaria
EOL staff
Life cycle of Trichomonas vaginalis, the cause of trichomoniasis in humansTrichomonas vaginalis resides in the female lower genital tract and the male urethra and prostate (1), where it replicates by binary fission (2). The parasite does not appear to have a cyst form, and does not survive well in the external environment. Trichomonas vaginalis is transmitted among humans, its only known host, primarily by sexual intercourse (3).From Centers for Disease Control Parasites and Health website
Centers for Disease Control/Division of Parasitic Diseases and Malaria
EOL staff
Life cycle of the flagellate Pentatrichomonas hominisPentatrichomonas hominis is a trichomonad flagellate with a worldwide distribution. Only trophozoites are shed in feces (1) as there is no known cyst stage for this species. Infection occurs after the ingestion of trophozoites in fecally-contaminated food or water or on fomites (i.e., other non-living objects or substances that can transmit them) (2). These organisms reside in the large intestine, where they are regarded as commensals (i.e., benefiting from but not harming their host) and are not known to cause disease in humans.From Centers for Disease Control Parasites and Health website
Description: English: Trichomonas vaginalis (arrows) from a vaginal swab stained by Gram's method. Date: 23 April 2021, 14:26:37. Source: Own work. Author: Dr Graham Beards.
Description: English: This photomicrograph of a wet-mounted vaginal discharge specimen, revealed numbers of Trichomonas vaginalis protozoan parasites, leading to a diagnosis of trichomoniasis, which is a very common sexually transmitted disease (STD) caused by the protozoan, T. vaginalis. Although symptoms of the disease vary, most women and men, who harbor the parasite, are unaware that they are infected. Date: 1975. Source: https://phil.cdc.gov/Details.aspx?pid=14500. Author: CDC/ Joe Miller.
Description: English: Diseases of metabolism and of the blood, animal parasites, toxicology. Publisher: New York and London, D. Appleton and Company. Contributing Library: Cornell University Library. Date: 1909. Source: https://www.flickr.com/photos/internetarchivebookimages/20533953569/. Author: Cabot, Richard C. (Richard Clarke), 1868-1939. ed; Salinger, Julius Lincoln.
Description: English: This phase contrast wet mount micrograph of a vaginal discharge revealed the presence of Trichomonas vaginalis protozoa. Date: 27 November 2012. Source: http://www.publicdomainfiles.com/show_file.php?id=13539998413331. Author: CDC, Courtesy: Public Health Image Library.
Description: English: This is an illustration of the life cycle of Trichomonas vaginalis, the causal agent of Trichomoniasis. Date: 2 December 2012. Source: http://www.publicdomainfiles.com/show_file.php?id=13544407214165. Author: CDC/Alexander J. da Silva, PhD/Melanie Moser.
