Press Release

Case of invasive meningococcal infection under CHP investigation

25 July 2013

The Centre for Health Protection (CHP) of the Department of Health is today (July 25) investigating a confirmed case of invasive meningococcal infection, a communicable disease transmitted by direct contact with droplets from carriers or infected persons, and hence appealed to the public for vigilance.

The 54-year-old female patient, with chronic illnesses, has presented with fever, chills and right ankle swelling since July 16. She was admitted to Prince of Wales Hospital on July 18 for management.

The clinical diagnosis is septic arthritis and she is currently in stable condition.

The specimen collected from her right ankle joint grew Neisseria meningitides, the bacteria causing meningococcal infection, upon laboratory testing.

The patient has no recent travel history. Her daughter had upper respiratory tract infection symptoms on July 11 and has recovered. The other home contact has remained asymptomatic. The CHP's investigation is proceeding.

This is the first confirmed case of invasive meningococcal infection reported to the CHP this year. Four cases were filed in 2012 while eight were reported in 2011.

A CHP spokesman explained that meningococcal infection is caused by a bacterium known as meningococcus. It is mainly transmitted by direct contact through respiratory secretions, including droplets from the nose and throat, from infected persons. The incubation period varies from two to 10 days, commonly three to four days.

The clinical picture may vary. Severe illness may result when the bacteria invades the bloodstream (meningococcaemia) or the membranes that envelope the brain and spinal cord (meningococcal meningitis).

Meningococcaemia is characterised by sudden onset of fever, intense headache, purpura, shock and even death in severe cases. Meningococcal meningitis is characterised by high fever, severe headache, stiff neck followed by drowsiness, vomiting, fear of bright light, or a rash. It can cause brain damage or even death. The brain damage may lead to intellectual impairment, mental retardation, hearing loss and electrolyte imbalance. For invasive meningococcal infections, it can be complicated by arthritis, inflammation of heart muscle, inflammation of the posterior chamber of the eye or chest infection.

Meningococcal infection is a serious illness. Patients should be treated promptly with antibiotics.

To prevent meningococcal infection, members of the public are advised to take heed of the following measures:

• Wash hands with liquid soap and water properly especially when they are dirtied by respiratory secretions, e.g. after sneezing, and clean hands with alcohol-based handrub when they are not visibly soiled;
• Cover the nose and mouth while sneezing or coughing, hold the spit with tissue, dispose of nasal and mouth discharge in lidded rubbish bins, and wash hands immediately;
• Avoid crowded places;
• Avoid close contact with patients who have fever or severe headache;
• Travellers to high-risk areas may consult doctors for meningococcal vaccination; and
• Travellers returning from high-risk areas should seek medical advice if they become ill and should discuss their recent travel history with their doctors.

The public may visit the CHP's website ( www.chp.gov.hk/en/content/9/24/2086.html ) for more information on meningococcal infection.