Chlamydia

• Most commonly reported communicable disease in Australia.
• Highest prevalence: Persons aged ≤24 years.
• Serious sequelae in women: PID (Pelvic Inflammatory Disease), ectopic pregnancy, and infertility.
• Frequently asymptomatic.Common asymptomatic infection: Among both men and women.
• No immunity provided by previous infection.
• Untreated chlamydia can remain asymptomatic for a long time; ~50% of infections resolve spontaneously within 1 year.

Sample Collection

• Clinician-collected | Self-collection
  • Asymptomatic patients can self-collect vaginal, anorectal, and throat swabs.
  • NAATs (Nucleic Acid Amplification Tests) are highly sensitive, usable in non-clinical settings, and the only recommended test.

Indications for Testing

• < 30 years and sexually active.
• Partner change in the last 12 months.
• Previous STI in the past 12 months.
• Sexual partner with an STI.
• Pregnant individuals.
• Increased risk of STI complications (e.g., termination of pregnancy, IUD insertion).
• Symptoms suggestive of chlamydia.
• Requesting a sexual health check.

Mode of Transmission

• Contact with exudate from mucous membranes: Transmission almost always occurs as a result of:
  • Sexual activity.
  • Perinatal transmission.

Timeline

• Incubation Period:
  • Poorly defined, typically 7 to 14 days or more.
• Period of Communicability:
  • Unknown.
  • Relapses are common.
  • Infected individuals may be intermittently infectious over many months.

Clinical Presentation

Clinical manifestations of chlamydial infections are difficult to distinguish from gonorrhoea. Symptoms are not necessarily present in all cases.

• Asymptomatic Infections: Common in both men and women.
• Men:
  • Urethral Discharge: The usual clinical presentation.
  • Proctitis: May occur in individuals practicing receptive anal intercourse.
• Women:
  • Mucopurulent Cervicitis: The usual presentation.
• Symptoms in Both Men and Women
  • Conjunctivitis: Redness, discharge, and irritation of the eyes.
  • Pharyngitis: Sore throat and swollen lymph nodes (rare and usually asymptomatic).
• Neonates (Congenital Chlamydia):
  • Conjunctivitis: Eye redness, discharge, and swelling.
  • Pneumonia: Respiratory distress, coughing, and rapid breathing.

Complications

• Men: Epididymo-orchitis.
• Women: Pelvic inflammatory disease (PID), infertility, ectopic pregnancy, premature rupture of membranes, preterm delivery, low-birthweight infants, ophthalmia neonatorum, pneumonia.
• Others: Reactive arthritis, perihepatitis (Fitz-Hugh-Curtis Syndrome).

Treatment

• Uncomplicated genital/pharyngeal infection:
  • Doxycycline 100 mg PO, BD for 7 days (first line)
  • Azithromycin 1 g PO, stat. (Consider where adherence to daily treatment likely to be poor especially where anorectal infection is less likely.)
• Anorectal infection:
  • Doxycycline 100 mg PO, BD for 7 days if asymptomatic; 21 days if symptomatic.
  • Azithromycin 1 g PO, stat. and repeat in 12-24 hours.
• Pregnant individuals:
  • Azithromycin 1 g PO, stat.
• Rectal co-infection with gonorrhoea:
  • Ceftriaxone 500 mg IMI, stat. in 2 mL 1% lignocaine.
  • Doxycycline 100 mg PO, BD for 7 days if asymptomatic; 21 days if symptomatic.

Follow-up and Contact Tracing

• Contact tracing: Back for 6 months.
  • Recommend treatment only for those unlikely to await test results.
  • Immediate treatment of sexual contacts not recommended.
  • Patient-delivered partner therapy for partners unlikely to seek testing/treatment.
  • No sexual contact for 7 days post-treatment.
  • No sex with partners from the last 6 months until tested and treated.
  • Provide a patient factsheet.
  • Notify state/territory health department.

Follow-up Care

• Confirm adherence to treatment and symptom resolution.
• Verify contact tracing or provide support.
• Test of cure:
  • Not routinely recommended, except for pregnant individuals and anorectal infections.
  • Test 4 weeks post-treatment to prevent false positives.
• Test for re-infection:
  • Re-infection is common
  • Retesting at 3 months is recommended to detect re-infection.

Prevention Strategies for STDs

1. Barrier use:
   • Consistently use male or female condoms during vaginal, anal, and oral sex. Ensure correct and consistent use to maximize effectiveness.
   • Recommend the use of dental dams or condoms during oral sex to prevent transmission of STDs.
2. Regular Screening:
   • Encourage routine STD testing for sexually active individuals, especially those with multiple partners.
   • Emphasize the importance of early detection and treatment to prevent complications and transmission.
3. Vaccination:
   • Promote vaccination against HPV and Hepatitis B, which can prevent related STDs.
4. Monogamous Relationships:
   • Discuss the importance of safe sex practices regardless of the number of partners.
   • Offer counseling and support for patients who have multiple partners or are in non-monogamous relationships to help them navigate safe practices.
   • Advise limiting the number of sexual partners to reduce exposure risk.
5. Avoid Sharing Needles:
   • Promote the use of clean needles for those who inject drugs to prevent blood-borne STDs like HIV and Hepatitis.
6. Pre-Exposure Prophylaxis (PrEP):
   • Consider PrEP for individuals at high risk of HIV infection.
7. Post-Exposure Prophylaxis (PEP):
   • Offer PEP for individuals who may have been exposed to HIV within the last 72 hours.
8. Communication with Partners:
   • Encourage open and honest communication with sexual partners about STD status and testing history.
9. Educate about Symptoms:
   • Teach individuals to recognize the symptoms of STDs and to seek medical evaluation if symptoms occur.
10. Partner Treatment:
    • Ensure that sexual partners are also treated to prevent reinfection and further spread.