What is Meningococcal Infection?
Meningococcal Infection is caused by the bacteria Neisseria meningitidis. The disease is mainly transmitted by droplets via coughing or sneezing or by direct contact through respiratory secretions from infected persons. The incubation period varies from 2 – 10 days, commonly 3 – 4 days. The clinical picture may be variable. It may result in severe illness when the bacteria invade the bloodstream (meningococcaemia) or the membranes that envelop 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 rash; it can cause brain damage or even death. The brain damage may lead to intellectual impairment, mental retardation, hearing loss and electrolyte imbalance.
What is the risk of acquiring the disease for travellers?
In general, the risk of acquiring meningococcal infection while travelling is low. However, the disease incidence is higher in sub-Saharan Africa extending from Senegal to Ethiopia (African meningitis belt), particularly during the dry season (December to June) and hence a higher risk of contracting the disease. Moreover, the risk for long-stay travellers living in close contact with the indigenous population is also higher.
How can you prevent it?
Meningococcal infection is transmitted by droplets via coughing or sneezing or by direct contact through respiratory secretions from infected persons. Therefore, travellers should pay attention to the following points:
- Wash hands properly and frequently, and observe good personal and environmental hygiene;
- Avoid going to crowded or poorly ventilated places; high-risk individuals may consider putting on surgical masks while in such places;
- Avoid close contact with patients having fever or severe headache;
- Cover the nose and mouth when coughing or sneezing and dispose of nasal and mouth discharge in lidded rubbish bin; wash hands immediately afterwards.
Meningococcal vaccines have been registered in Hong Kong. To minimise the risk of meningococcal infection, vaccination may be considered for the following groups of travellers:
- Travellers to the sub-Saharan Africa during the dry season according to the risk of exposure and local epidemic situations;
- Travellers to areas that are known to experience epidemic meningococcal disease as announced by authorities; and
- Travellers aged over 2 years visiting Saudi Arabia for Hajj, Umrah or for seasonal work in Hajj zones should bring along certificate of vaccination with the quadrivalent (serogroups A,C,Y & W135) meninogococcal vaccine administered not less than 10 days before arrival in Saudi Arabia. Further information is available at the website of the Ministry of Health of the Saudi Arabia (https://www.moh.gov.sa/en/Pages/Default.aspx).
Travellers should seek professional advice from doctors for vaccination in view of the individual’s age and health condition, and details of the journey such as place, duration and nature.
How is it treated?
Meningococcal infection is a serious illness. Patients must be treated promptly with antibiotics. Close contacts should be placed under surveillance to observe for early symptoms of the disease and may need to take preventive medications as necessary.