It is caused by the bacteria Neisseria meningitidis of which there are 6 disease-causing strains called serogroups (A, B, C, W, Y and X). Approximately 10 percent of the general population of the UK are thought to carry N. meningitidis in the lining of the nose and throat. Spread between individuals occurs through coughing, sneezing, kissing or during close contact with a carrier. Carriers do not have symptoms, but can develop disease when bacteria invade the bloodstream from the nasopharynx (area at the back of the nose and throat). Invasive disease is a rare but serious outcome usually presenting as septicaemia (blood poisoning) or meningitis (infection of the lining of the brain).

In most parts of the world meningococcal disease occurs as occasional cases in individuals or in small clusters. The disease is most common in the ‘meningitis belt’ of sub-Saharan Africa, which extends across the dry savannah regions from Senegal in the west, to Ethiopia in the east. These outbreaks occur particularly during the dry season and whilst previously most dominant serogroup, outbreaks due to serogroup A have virtually disappeared since the introduction of large vaccination campaings. Serogroups W, C and X are still responsible for localised epidemics and occasionally widespread epidemic waves.

Following several large outbreaks associated with pilgrimage to the Kingdom of Saudi Arabia all those travelling for the Hajj or Umrah and seasonal workers to this area, are currently required to show proof of vaccination with quadrivalent vaccine (protecting against the A, C, W and Y serogroups) in order to obtain a visa.

Invasive meningococcal disease usually presents as meningitis or septicaemia. Symptoms of meningitis include: sudden onset of fever, intense headache, neck stiffness, nausea and vomiting. Symptoms of septicaemia include: fever, chills, confusion and a rash. Both conditions may progress rapidly and are serious diseases with high risk of complications and fatality.

Prevention

Individuals should seek advice about their risk of meningitis prior to travel. Meningococcal disease in travellers is primarily a risk for those visiting areas prone to outbreaks or an area where a known outbreak is occurring. Travellers visiting such locations who are at particular risk include:

• long stay travellers who have close contact with the local population
• healthcare workers
• those visiting friends and relatives
• those travelling for Hajj and Umrah
• those who live or travel ‘rough’ such as backpackers
• individuals with no spleen or a poorly functioning spleen
• individuals with certain immune deficiencies