Chlamydia and Gonorrhea—Clinician FAQ

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The Task Force recommends opportunistic screening for chlamydia and gonorrhea at primary care visits, using a self- or clinician-collected sample.

Conditional recommendation; very-low-certainty evidence

1. Who does this recommendation apply to?

  • It applies to all sexually active individuals under 30 years of age.
    • Sexual activity is defined as ever having oral, vaginal or anal intercourse
    • Most cases occur in Canadians under age 30 with increasing rates between ages 15 – 29
    • Evidence of benefit for screening
  • This extends the eligible screening population from previous Canadian guidance to reflect increasing rates of infection among those aged 25 to 29 years.

2. Who does this recommendation not apply to?

  • It does not provide guidance for pregnant patients, individuals known to belong to a high-risk group or patients specifically seeking care for a possible sexually transmitted infection (STI).
  • Pregnant patients and those who are seeking testing or who are known to belong to a high-risk group should be managed following applicable national, provincial, or local guidance.
  • High-risk includes having multiple sexual partners, previous STI’s or having sex without a condom.

3. Why are we recommending screening?

  • Chlamydia and gonorrhea are the most commonly reported bacterial sexually transmitted infections in Canada.
    • 1 in 20 sexually active individuals 15-29 years old will get chlamydia
  • This recommendation supports an uncertain but potentially important benefit of reducing pelvic inflammatory disease in females.
  • Screening of males may help prevent negative health consequences in females.
  • Patients under 30 generally prioritize the benefits over the harms of screening and have shown a strong preference to be screened.
  • Individuals at high risk of infection may not always readily self-identify or be easily identified by clinicians.
    • This routine offer to screen may reduce barriers to screening and improve health equity by normalizing screening
  • We have included both chlamydia and gonorrhea in this recommendation since they are tested together.

4. How often should screening take place?

  • An annual offer of screening may be appropriate for individuals at general risk, recognizing that encounters with primary care may occur less frequently.

5. What are the harms of screening?

  • Some individuals eligible for screening may experience psychosocial harms of embarrassment, anxiety, or stigma.
  • While no serious adverse effects of antibiotic treatment for chlamydia or gonorrhea were found in studies, there is potential for minor harms (nausea and diarrhea) and allergic reactions.
  • A false positive result could cause psychological harm without benefit to some individuals. False positives are more likely to occur when prevalence is low.
  • Based on the approximate prevalence of chlamydia (5%) and gonorrhea (1%) in the target population, the expected range of false positive tests is:
    • In individuals who are assigned female at birth, approximately 8-9% of chlamydia tests and 45-70% of gonorrhea tests (depending on various factors)
    • In individuals who are assigned male at birth, approximately 13-15% of chlamydia tests and 24-50% of gonorrhea tests (depending on various factors)

6. How should I implement this recommendation?

  • Identify eligible individuals, those who are sexually active and under 30 years of age.
  • Offer screening opportunistically.
    • i.e., without requiring a separate screening visit, and not only during sexual health visits
  • Keep in mind that screening requires sensitivity to fear, anxiety and feelings of embarrassment for some people.
    • Consider this example of a non-judgmental offer of screening: “screening is offered routinely for everyone under 30 who is sexually active”
  • Acceptability and uptake of screening may be improved by minimally invasive sample collection methods, of which self-collected vaginal swabs from females and urine samples from males are the most accurate.
  • Undertake informed consent for STI testing.
    • Address privacy and reporting requirements for positive test results to local public health offices and potential partner notification