Psittacosis—also known as parrot fever, and ornithosis—is a zoonotic infectious disease in humans caused by a bacterium called Chlamydia psittaci and contracted from infected parrots, such as macaws, cockatiels, and budgerigars, and from pigeons, sparrows, ducks, hens, gulls and many other species of birds. The incidence of infection in canaries and finches is believed to be lower than in psittacine birds.
Chlamydia trachomatis, commonly known as chlamydia, is a bacterium that causes chlamydia, which can manifest in various ways, including: trachoma, lymphogranuloma venereum, nongonococcal urethritis, cervicitis, salpingitis, pelvic inflammatory disease. C. trachomatis is the most common infectious cause of blindness and the most common sexually transmitted bacterium.
The Chlamydiota are a bacterial phylum and class whose members are remarkably diverse, including pathogens of humans and animals, symbionts of ubiquitous protozoa, and marine sediment forms not yet well understood. All of the Chlamydiota that humans have known about for many decades are obligate intracellular bacteria; in 2020 many additional Chlamydiota were discovered in ocean-floor environments, and it is not yet known whether they all have hosts. Historically it was believed that all Chlamydiota had a peptidoglycan-free cell wall, but studies in the 2010s demonstrated a detectable presence of peptidoglycan, as well as other important proteins.
Circoviridae is a family of DNA viruses. Birds and mammals serve as natural hosts. There are 101 species in this family, assigned to 2 genera. Diseases associated with this family include: PCV-2: postweaning multisystemic wasting syndrome; CAV: chicken infectious anemia.
Chlamydia pneumoniae is a species of Chlamydia, an obligate intracellular bacterium that infects humans and is a major cause of pneumonia. It was known as the Taiwan acute respiratory agent (TWAR) from the names of the two original isolates – Taiwan (TW-183) and an acute respiratory isolate designated AR-39. Briefly, it was known as Chlamydophila pneumoniae, and that name is used as an alternate in some sources. In some cases, to avoid confusion, both names are given.
Chlamydia psittaci is a lethal intracellular bacterial species that may cause endemic avian chlamydiosis, epizootic outbreaks in mammals, and respiratory psittacosis in humans. Potential hosts include feral birds and domesticated poultry, as well as cattle, pigs, sheep, and horses. C. psittaci is transmitted by inhalation, contact, or ingestion among birds and to mammals. Psittacosis in birds and in humans often starts with flu-like symptoms and becomes a life-threatening pneumonia. Many strains remain quiescent in birds until activated by stress. Birds are excellent, highly mobile vectors for the distribution of chlamydia infection, because they feed on, and have access to, the detritus of infected animals of all sorts.
Brucella is a genus of Gram-negative bacteria, named after David Bruce (1855–1931). They are small, nonencapsulated, nonmotile, facultatively intracellular coccobacilli.
Erysipelothrix is a genus of bacteria containing four described species, Erysipelothrix rhusiopathiae, Erysipelothrix tonsillarum, Erysipelothrix inopinata and Erysipelothrix larvae. Additional species have been proposed based on DNA-DNA hybridization studies "The hallmark of Erysipelothrix is the presence of a type B cell wall, in which the peptide bridge is formed between amino acids at positions 2 and 4 of adjacent peptide side-chains and not, as in the vast majority of bacteria, between amino acids at positions 3 and 4."
Chlamydophila is a controversial bacterial genus belonging to the family Chlamydiaceae.
The Chlamydiaceae are a family of gram-negative bacteria that belongs to the phylum Chlamydiota, order Chlamydiales. Chlamydiaceae species express the family-specific lipopolysaccharide epitope αKdo-(2→8)-αKdo-(2→4)-αKdo. Chlamydiaceae ribosomal RNA genes all have at least 90% DNA sequence identity. Chlamydiaceae species have varying inclusion morphology, varying extrachromosomal plasmid content, and varying sulfadiazine resistance.
Chlamydia muridarum is an intracellular bacterial species that at one time belonged to Chlamydia trachomatis. However, C. trachomatis naturally only infects humans and C. muridarum naturally infects only members of the family Muridae.
Chlamydia suis is a member of the genus Chlamydia. C. suis has only been isolated from swine, in which it may be endemic. Glycogen has been detected in Chlamydia suis inclusions in infected swine tissues and in cell culture. C. suis is associated with conjunctivitis, enteritis and pneumonia in swine.
Chlamydia felis is a Gram-negative, obligate intracellular bacterial pathogen that infects cats. It is endemic among domestic cats worldwide, primarily causing inflammation of feline conjunctiva, rhinitis and respiratory problems. C. felis can be recovered from the stomach and reproductive tract. Zoonotic infection of humans with C. felis has been reported. Strains FP Pring and FP Cello have an extrachromosomal plasmid, whereas the FP Baker strain does not. FP Cello produces lethal disease in mice, whereas the FP Baker does not. An attenuated FP Baker strain, and an attenuated 905 strain, are used as live vaccines for cats.
Chlamydia caviae is a bacterium that can be recovered from the conjunctiva of Guinea pigs suffering from ocular inflammation and eye discharge. It is also possible to infect the genital tract of Guinea pigs with C. caviae and elicit a disease that is very similar to human Chlamydia trachomatis infection. C. caviae infects primarily the mucosal epithelium and is not invasive.
Chlamydia pecorum, also known as Chlamydophila pecorum is a species of Chlamydiaceae that originated from ruminants, such as cattle, sheep and goats. It has also infected koalas and swine. C. pecorum strains are serologically and pathogenically diverse.
Chlamydia is a genus of pathogenic Gram-negative bacteria that are obligate intracellular parasites. Chlamydia infections are the most common bacterial sexually transmitted diseases in humans and are the leading cause of infectious blindness worldwide.
Chlamydia is a sexually transmitted infection caused by the bacterium Chlamydia trachomatis.
Parachlamydia acanthamoebae are bacterium that fall into the category of host-associated microorganisms. This bacterium lives within free-living amoebae that are an intricate part of their reproduction. Originally named Candidatus Parachlamydia acanthamoebae, its current scientific name was introduced shortly after. This species has shown to have over eighty percent 16S rRNA gene sequencing identity with the class Chlamydiia. Parachlamydia acanthamoebae has the same family as the genus Neochlamydia with which it shares many similarities.
Chlamydia research is the systematic study of the organisms in the taxonomic group of bacteria Chlamydiota, the diagnostic procedures to treat infections, the disease chlamydia, infections caused by the organisms, the epidemiology of infection and the development of vaccines. The process of research can include the participation of many researchers who work in collaboration from separate organizations, governmental entities and universities.
