Meningococcal disease: notification and contact prophylaxis
The case
A 19-year-old university student presents with 10 hours of fever to 39.8°C, severe headache, photophobia, neck stiffness and a non-blanching petechial rash progressing to purpura. Cerebrospinal fluid shows Gram-negative intracellular diplococci with neutrophils, and blood cultures grow Neisseria meningitidis serogroup B. She deteriorates and is admitted to intensive care. What is the single most appropriate public health measure for her four household contacts?
Options
- ANotify the public health unit urgently and give clearance antibiotics to household contacts
- BQuarantine the contacts for 7 days and give MenB vaccine
- CCiprofloxacin only after throat swabs are negative
- DIssue a university-wide alert and exclude her classmates
- EGive MenACWY vaccine to contacts before any antibiotics
Think it through before you read on. Which single option is best, and why are the other four wrong?
Show the answer and explanation
Answer
A. Notify the public health unit urgently and give clearance antibiotics to household contacts
Why this is the right answer
Invasive meningococcal disease is a nationally notifiable condition in Australia. The treating doctor must notify the state or territory public health unit immediately by telephone on clinical suspicion, without waiting for laboratory confirmation. This is a legal duty under public health legislation and it overrides confidentiality.
The public health unit then coordinates the response according to the Communicable Diseases Network Australia (CDNA) national guidelines. The main measure is clearance (chemoprophylaxis) antibiotics for close contacts, given as soon as possible and ideally within 24 hours. The aim is to eradicate nasopharyngeal carriage in people who may have acquired the organism from the case, and so prevent secondary cases. Household contacts have a risk several hundred times the general population in the first week.
Close contacts are household members, anyone who slept in the same dwelling in the 7 days before onset, intimate kissing contacts, childcare contacts, and health workers who had unprotected exposure to respiratory secretions (for example during intubation). Casual contacts such as classmates or workmates do not need prophylaxis.
The CDNA guideline lists ciprofloxacin (single oral dose), rifampicin (2 days) and ceftriaxone (single injection) as clearance antibiotics, with the choice depending on age, pregnancy and availability. Antibiotics are not delayed for throat swabs, which cannot reliably exclude carriage. The index case also needs clearance antibiotics before discharge unless treated with ceftriaxone.
Vaccination of contacts with the matching vaccine (MenB here) may be offered by the public health unit as an additional measure, but it takes weeks to protect and never replaces antibiotics.
Why the other options are wrong
- B
Quarantine is not used; the response is antibiotics, with vaccine as an adjunct that cannot substitute for them.
- C
Throat swabs do not exclude carriage; waiting for them delays prophylaxis past its useful window.
- D
Classmates are casual contacts and do not need prophylaxis; a campus alert is a public health unit decision.
- E
The organism is serogroup B, which MenACWY does not cover, and vaccine never precedes or replaces antibiotics.
High-yield takeaway
Suspected meningococcal disease: phone the public health unit at once, and close (household and kissing) contacts get clearance antibiotics within 24 hours, not swabs, quarantine or vaccine alone.
Reference: CDNA National Guidelines for Public Health Units: Invasive Meningococcal Disease (2023)
Common questions
Who counts as a close contact of meningococcal disease?
Household members, anyone who slept in the same dwelling in the previous week, intimate kissing contacts, childcare contacts and health workers with unprotected exposure to secretions.
Do classmates or workmates need antibiotics?
No. Casual contacts are not at significantly increased risk and are not given prophylaxis.
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