ChlamydiaKaren HardtMegan HaysLesley KrugerMicrobiology 240Disease Research ProjectProfessor KibotaJuly 17, 2005ChlamydiaThe genus Chlamydia has three different species (Taber’s, 1997). They includeChlamydia pneumoniae, Chlamydia psittaci, and Chlamydia trachomatis (Taber’s, 1997).C. pneumoniae causes respiratory disease in humans while C. psattaci causes sever flu-like symptoms as a result of contact with infected birds (Taber’s, 1997). The mostprevalent of the three is C. trachomatis which is commonly known as Chlamydia. Thistype is contracted via secretions of infected individuals primarily through sexual contact,and is the species explored further in this paper.In 1903, interested in the pathogen which caused syphilis, Neisser traveled to theisland of Java with two other scientists, Ludwig Halberstaedter and Stanislaus vonProwazek (Dimitrakov, 2002). In 1907, Halberstaedter and von Prowazek took scrapingsfrom individuals infected with trachoma (which they believed to be a protozoan), andinoculated orangutans eyes with the samples (Fields and Barnes, 1999). Thisdemonstrated how the disease could be spread between infected individuals (Dimitrakov,2002). However, this posed the question of how newborns could acquire the diseasewithout contact (Dimitrakov, 2002). In 1929, an epidemic of pneumonia originatingfrom contact with infected parrots gained notoriety (Fields and Barnes, 1999). In 1935,Chlamydia was thought to be a virus because it could only exist in living cells, since theyuse them for energy (Fields and Barnes, 1999). It wasn’t until the 1960’s that Chlamydiawas confirmed to be a bacteria, with the discovery that it contained both DNA and RNA,ribosomes, and cell walls – structures typical of bacteria (Mayer, 2005; Whipple et al.,2005).Chlamydia is a gram-negative bacterium which lacks peptidoglycan (Dimitrakov,2002; Mayer, 2005). Because it does not contain peptidoglycan, the bacteria are notaffected by penicillin (Dimitrakov, 2002). The cell wall does contain alipopolysaccharide layer common to other gram-negative bacteria (Mayer, 2005; Whippleet al., 2005). A single Chlamydia cell is approximately 350 nm and is coccus shaped(Dimitrikov, 2002; Fields and Barnes, 1999). This bacterium cannot manufacture its ownATP; instead, it requires a living host to obtain the ATP needed for energy (Dimitrakov,2002; Mayer, 2005).Chlamydia has two developmental stages – the elementary body (EB) and thereticulate body (RB)(Dimitrakov, 2002; Mayer, 2005). The elementary body is the stagewhen infection of the host occurs (Dimitrakov, 2002; Mayer, 2005). In this stage, thebacteria are in a state similar to that of an endospore, where the outer membrane isresistant to the environment and allows it to exist without a host cell (Fields and Barnes,1999; Mayer, 2005). Once the elementary body finds a host, the host cell engulfs itthrough endocytosis, and the host becomes infected (Dimitrakov, 2002; Mayer, 2005).Inside the host cell, a vacuole encloses the elementary body and the bacteria transitionsinto the reticulate, or non-infectious, body (Dimitrakov, 2002; Mayer, 2005; Fields andBarnes, 1999). In this state, the bacteria use the host cell’s ATP to reproduce throughbinary fission (Dimitrakov, 2002; Mayer, 2005). The vacuole that encloses the bacteriaprotects the reticulate body from cellular lysosomes and prevents them from beingeliminated by these defense mechanisms (Dimitrakov, 2002; Mayer, 2005). Afterdivision, the reticulate body transforms back to the elementary form and is released fromthe cell through exocytosis (Demets, 1998). The elementary bodies then go on to infectother host cells, where the process continues, and the infection spreads (Demets, 1998).Whereas the elementary body does not require a host cell to survive, the reticulate body isdependent on a host cell for survival (Dimitrkov, 2002; Mayer, 2005).Most Chlamydial bacteria affect the epithelial cells of humans, where mucousmembranous tissues are found (Mayer, 2005). The most prevalent area of infection is theurogenital tract (NIAID, 2004; Houry, 2004), but infection can also occur in the eyes andthe respiratory tract (Mayer, 2005; NIAID, 2004). Symptoms generally occur one tothree weeks after contact with an infected individual (NIAID, 2004; CDC, 2005).The symptoms of Chlamydia in women include vaginal discharge, cramps or painin the lower abdomen, and a burning sensation while urinating (Maryland Dept. ofHealth, 2004; Hwang, 1998). Although these symptoms can occur, 80% of womeninfected do not experience any symptoms (Houry, 2004). Left untreated, Chlamydia isthe leading cause of pelvic inflammatory disease in women, and can also cause infertility.Scarring of the fallopian tubes by the disease can lead to ectopic pregnancy which resultsin miscarriage and possible death of the woman (Hwang, 1998; NIAID, 2004).As with women, men may not experience and symptoms (Maryland Dept. ofHealth, 2004). If symptoms due exist, they can range from penal discharge, painfulurination with itching or burning, to testicular tenderness (Maryland Dept. of Health,2004; Hwang, 2004; NIAID, 2004). Possible long-term effects in men can beepididymitis (inflammation of the epdidymis, the tubes at the upper part of each testicle),sterility, and inflammation of the prostate or rectum (Dimitrakov, 2002; Hwang, 1998;NIAID, 2004).Infected women can pass Chlamydia to their newborn during birth. This can be inthe form of conjunctivitis or pneumonia, and usually develops within the first ten days oflife (Hwang, 1998; NIAID, 2004). Chlamydia can also result in premature birth (Hwang,1998; NIAID, 2004).Tests for Chlamydia previously included swabbing the cervix of a woman or theurethra of a man and took days to obtain results (Kaiser Foundation, 2005). Recently, anew test has been developed that uses an urinalysis sample or a sample swabbed from thevagina (Kaiser Foundation, 2005). This test is named the Firstburst Test, and is lessexpensive, less time-consuming, and less uncomfortable than previous tests (KaiserFoundation, 2005).In response to a Chlamydial infection, the human body will produce antibodies(Fields and Barnes, 1999). However, these antibodies only inhibit the growth of theinfection; they do not destroy the bacteria (Fields and Barnes, 1999). Since the bodycannot fight the bacteria on its own, other measures must be taken to cure the disease.Treatment of Chlamydia includes the