12CATEDRAL-_-CHLAMYDIA
CHLAMYDIA PRESENTATION
Presented by: John Michael V. Catedral, DVM 3 - B
INTRODUCTION
Chlamydia trachomatis:
First described in historical records in Ebers papyrus (between 1553 and 1550 BC).
Definition:
Chlamydia refers to a genus of obligate intracellular pathogens.
Can only survive and reproduce within host cells.
Discovery:
Discovered in 1907 by Halberstaedter and von Prowazek in conjunctival scrapings from an infected orangutan.
Characteristics:
Responsible for various infectious diseases in animals and humans.
Divided into several species (e.g., Chlamydia psittaci, Chlamydia abortus).
TAXONOMY
Domain: Bacteria
Phylum: Chlamydia
Class: Chlamydiae
Order: Chlamydiales
Family: Chlamydiaceae
Genus: Chlamydia
Scientific Name: Chlamydia trachomatis
CLASSIFICATION
Genera Include:
Chlamydia, Chlamydophila, and Parachlamydia.
Notable Species:
Chlamydia trachomatis: Causes trachoma, leading cause of preventable blindness, also genital infections.
Chlamydophila pneumoniae: Causes respiratory infections in humans.
Chlamydophila psittaci: Infects birds causing psittacosis.
Chlamydophila felis: Causes conjunctivitis in cats.
CHLAMYDIAE
Small, spherical intracellular bacteria with unique developmental cycles.
Staining Methods:
Modified Ziehl-Neelsen, Giemsa.
Metabolism:
Cannot synthesize ATP; replicate only in living cells.
Cell Wall Composition:
Lack peptidoglycan; contain family-specific lipopolysaccharides.
Pathogenic Impact:
Cause diseases in respiratory, enteric, and reproductive tracts.
LIFE CYCLE OF CHLAMYDIAE
Stages:
Elementary Body (EB) - Infectious stage that attaches and enters host cells.
Reticulate Body (RB) - Replicative form that multiplies through binary fission.
Transition back to EB before host cell lysis.
Detailed Steps:
Attachment & Entry: EB enters via endocytosis.
Reticulate Body Formation: EB differentiates into RB once inside.
Replication & Multiplication: RB multiplies within host cell.
Assembly & Release: New EBs released to infect other cells.
DEVELOPMENTAL CYCLE
Characteristics of EBs:
Small (200-300 nm), metabolically inert.
Surrounded by a cytoplasmic membrane and an outer envelope with lipopolysaccharides.
Host Interaction:
Enter host cells by receptor-mediated endocytosis.
Conversion:
EBs reorganize into RBs, which reproduce and form inclusions within the cytoplasm.
Replication:
Continues for up to 72 hours, leading to cell lysis and release of infectious agents.
USUAL HABITAT
Infection often occurs in the gastrointestinal tract of animals.
Generally subclinical but can lead to prolonged intermittent shedding.
PATHOGENESIS AND TRANSMISSION
Infection Mechanism:
Infect epithelial cells; cause respiratory infections, abortions, conjunctivitis.
Transmission Routes:
Aerosol, direct contact with secretions, vertical transmission, environmental contamination.
PATHOGENESIS AND PATHOGENICITY
Infects over 450 species of birds and a large number of mammals, including humans.
Specific diseases often associated with particular hosts:
e.g., abortion in sheep caused by Chlamydophila abortus.
Infections often asymptomatic, localized, or persistent.
IMPORTANCE OF CHLAMYDIAE
Veterinary Pathogens:
Chlamydia abortus: Ovine enzootic abortion.
Chlamydia psittaci: Avian chlamydiosis.
Chlamydia felis: Feline conjunctivitis.
Disease Manifestations:
Lead to abortion in livestock, respiratory infections in birds and mammals, conjunctivitis in cats.
DIAGNOSTIC PROCEDURES
Specimen Handling:
Place in suitable transport medium (e.g., SPG) and keep at 4°C.
Detection Methods:
Direct microscopy, ELISA, polymerase chain reaction, serological tests.
CLINICAL SIGNS IN ANIMALS
Common Signs:
Ruminants: abortion, conjunctivitis.
Birds: respiratory distress.
Cats: conjunctivitis and ocular discharge.
Dogs: respiratory infections, especially in puppies.
Rabbits: conjunctivitis.
CLINICAL INFECTIONS
Severity varies widely; conditions range from mild to severe.
Common Diseases:
Conjunctivitis, abortion, pneumonia.
Human infections from psittacine species termed psittacosis.
Ovine Enzootic Abortion (OEA)
Characteristics:
Caused by Chlamydophila abortus.
Significant economic impact due to reduced lamb production.
Infection Process:
Spread through infected animals or environments, leading to fetal infection and abortion.
ENZOOTIC ABORTION OF EWES (EAE)
Primarily affects intensively managed flocks, causing significant economic losses.
Source of Infection:
Generally coincides with sheep management practices, particularly during birthing seasons.
EPIDEMIOLOGY OF EAE
Introduced through infected animals.
Organisms shed in placentas and secretions remain viable in the environment.
PATHOGENESIS IN EAE
Infection detected around day 90 of gestation; affects placenta leading to inflammation.
Consequences of Infection:
Abortion can occur due to various factors including maternal-fetal exchange challenges.
CLINICAL SIGNS IN EAE
Characterized by abortion during late pregnancy or weak lamb births.
Affected animals often show no clinical signs beyond reproductive issues.
DIAGNOSIS OF EAE
Suggestive signs include necrotic placentitis; EBs detectable in placental smears.
Techniques include PCR, serological tests, and culture.
TREATMENT AND CONTROL
Antibiotics:
Long-acting oxytetracycline is effective.
Control Measures:
Isolation of aborted ewes, thorough cleaning, possible vaccination strategy.
FELINE CHLAMYDIOSIS
Caused by: Chlamydophila felis.
Symptoms:
Conjunctivitis, rhinitis, pneumonia; highly contagious among cats.
EPIDEMIOLOGY OF FELINE CHLAMYDIOSIS
Infects approximately 10% of unvaccinated cats; spreads via secretions.
More common in multi-cat households; stress can exacerbate shedding.
CLINICAL SIGNS IN FELINE CHLAMYDIOSIS
Characterized by conjunctival inflammation and potential secondary infections.
DIAGNOSIS OF FELINE CHLAMYDIOSIS
Methods:
Conjunctival swabs, PCR, serological tests.
TREATMENT AND CONTROL OF FELINE CHLAMYDIOSIS
Systemic antibiotic treatment recommended.
Vaccines available but do not prevent infection.
PSITTACOSIS (AVIAN CHLAMYDIOSIS)
Caused by Chlamydophila psittaci; zoonotic risks.
Primary infections in birds can lead to severe consequences.
SYMPTOMS IN BIRDS AND HUMANS
Birds: lethargy, respiratory distress; humans: flu-like symptoms, pneumonia.
AVIAN CHLAMYDIOSIS
Various serotypes impacting different avian species based on serological reactions.
EPIDEMIOLOGY OF AVIAN CHLAMYDIOSIS
Widespread susceptibility among wild and domestic birds; stress factors increase shedding.
CLINICAL SIGNS IN AVIAN CHLAMYDIOSIS
Generalized infections with gastrointestinal and respiratory symptoms.
DIAGNOSIS OF AVIAN CHLAMYDIOSIS
Detection methods include staining, ELISA, PCR, and culture.
TREATMENT AND CONTROL OF AVIAN CHLAMYDIOSIS
Tetracyclines are effective; proper husbandry reduces disease occurrence.
SPORADIC BOVINE ENCEPHALOMYELITIS
Neurological disease linked to infection with C. pecorum.
Symptoms: fever, incoordination, and can lead to high mortality.
POLYARTHRITIS IN LIVESTOCK
Inflammation of multiple joints, variable in causative chlamydial species.
Diagnosis and Treatment: Clinical exam and antibiotics.
ZOONOTIC RISKS OF CHLAMYDIAE
Chlamydial infections can transmit from animals to humans; good hygiene reduces risks.
DIAGNOSTIC METHODS OF CHLAMYDIAE
Clinical Methods: Observation, lab diagnosis (microscopy, PCR).
TREATMENT AND PREVENTION OF CHLAMYDIAE
Antibiotics (tetracyclines), potential vaccines, hygiene practices essential.
CONTROL AND PREVENTION STRATEGIES
Emphasizes biosecurity, quarantine, and vaccination where applicable.