Neisseria meningitidis Exposure Prophylaxis Guidelines
Indications for Chemoprophylaxis
- Close contacts of a confirmed or probable case should receive chemoprophylaxis as soon as possible, ideally within 24 hours of case identification [CDC 1, 2].
Definition of Close Contacts
- Household members who lived with the patient during the 7 days before symptom onset are considered close contacts [CDC 3].
- Intimate kissing contacts are included as close contacts [Infection Journal 4].
- Anyone with direct exposure to the patient’s oral secretions (e.g., kissing, mouth‑to‑mouth resuscitation, airway management) qualifies as a close contact [CDC 3].
- Child‑care centre attendees who were exposed to the case are close contacts [CDC 3].
- Healthcare personnel who managed the patient’s airway or were exposed to respiratory secretions are close contacts [CDC 3].
- Airline passengers seated directly adjacent to the index patient on flights lasting ≥ 8 hours are close contacts [CDC 3].
Risk Justification
- The secondary attack rate among close contacts is 2–4 per 1,000, representing a ≈ 1,000‑fold increase over the background adult incidence of 0.23 per 100,000 [Infection Journal 5].
- The majority of invasive meningococcal disease is acquired within the 7 days preceding symptom onset [Infection Journal 5].
Recommended Antibiotic Regimens
First‑Line (Preferred) – Ciprofloxacin, Single Oral Dose
- Adults: 500 mg orally, single dose [Infection Journal 5].
- Children 5–12 years: 250 mg orally, single dose [Infection Journal 5].
- Children < 5 years: 30 mg/kg (maximum 125 mg) orally, single dose [Infection Journal 5].
- Preferred because of single‑dose convenience and wide availability; however, use should be modified in regions with documented ciprofloxacin resistance [CDC 1].
Alternative – Rifampicin, 2‑Day Course
- Adults and children > 12 years: 600 mg twice daily for 2 days [CDC 1].
- Children 1–12 years: 10 mg/kg twice daily for 2 days [Infection Journal 4].
- Infants < 12 months: 5 mg/kg twice daily for 2 days [Infection Journal 4].
- Contra‑indication: Not recommended in pregnancy due to teratogenicity and may reduce oral‑contraceptive efficacy [CDC 3].
Alternative – Ceftriaxone, Single Intramuscular Dose
- Adults: 250 mg IM, single dose [Infection Journal 5].
- Children < 15 years: 125 mg IM, single dose [Infection Journal 5].
Timing and Administration
- Prophylaxis should be initiated within 24 hours of identifying the index case for maximal effectiveness [CDC 3].
- Administration more than 14 days after exposure provides limited or no benefit [CDC 3].
- Do not delay treatment awaiting oropharyngeal culture results, as cultures do not alter management [CDC 3].
Coordination with Public Health Authorities
- Initiation of chemoprophylaxis is the responsibility of public‑health agencies (e.g., Communicable Disease Control teams), not the admitting clinicians, although clinicians may arrange prescriptions [CDC 1, 2].
- All meningococcal cases must be notified to the appropriate public‑health authority as a legal requirement [CDC 1, 2].
Additional Vaccination Considerations
- Unvaccinated close contacts of cases caused by vaccine‑preventable non‑B serogroups should receive the appropriate meningococcal vaccine [Infection Journal 4].
- If ≥ 2 serogroup B cases occur within the same household, Bexsero vaccination is recommended for all household contacts in addition to chemoprophylaxis [Infection Journal 4, 5].
Long‑Term Risk Management
- Even after appropriate chemoprophylaxis, close contacts retain an elevated risk for at least 6 months [CDC 1, 4].
- Medical records of all close contacts should be flagged to alert future providers of this persistent risk [CDC 1, 4].
Situations Where Prophylaxis Is Not Indicated
- Contacts of patients from whom N. meningitidis is isolated only from non‑sterile sites (e.g., oropharyngeal swabs, endotracheal secretions, conjunctival swabs) [CDC 3].
- Asymptomatic nasopharyngeal carriers [Infection Journal 5].
- Casual contacts without direct exposure to oral secretions [CDC 3].