Epidemiology

Meningococcal disease is the leading infectious cause of death in children, and can kill a healthy child within hours of first onset of symptoms.

Acute bacterial meningitis still causes substantial morbidity and mortality despite the availability of appropriate antibiotic therapy (Hoffman and Weber, 2009; Fitch, 2007).

 

Acute viral meningitis is vastly more common and infrequently carries a serious outcome. It is beyond the scope of this module to discuss viral meningitis.

 

The mortality rate of untreated bacterial meningitis approaches 100 percent and, even with optimal therapy, morbidity and mortality may occur (Kaplan, 2015)

 

Approximately 1.2 million cases of bacterial meningitis occur annually worldwide, with a severe morbidity and mortality rate of over 20% (van de Beek et al, 2012; WHO, 2015)

 

The World Health Organization has estimated that meningococcal disease causes at least 135,000 deaths annually.

 

There are approximately 3,200 cases of bacterial meningitis and septicaemia in the UK and Ireland annually, of which meningococcal infection is the most common (Figures 1 & 2, right, click to enlarge) (Meninigtis Research Foundation, 2015 c & 2015d).

 

The largest burden of meningococcal disease occurs in an area of sub-Saharan Africa known as the meningitis belt, which stretches from Senegal in the west to Ethiopia in the east. (Figure 3, right, click to enlarge) (WHO, 2015)

 

The most recent large-scale epidemic in the Belt occurred in 2009 and affected mainly Nigeria and Niger, causing over 80,000 reported cases. 

 

From 2010 to 2014 cases have been steadily decreasing, with approximately 24,000 cases in 2010 to 11,500 cases in 2014 (Figure 4, right, click to enlarge) (WHO, 2015)

Figure 1. Bacterial meningitis in the Republic of Ireland (Meningitis Research Foundation, 2015c)

Figure 2. Bacterial meningitis in the UK (Meningitis Research Foundation, 2015d)

Figure 3. Meningococcal meningitis, countries or areas at high risk, 2014 (WHO, 2015)

Figure 4. Trends of epidemic meningitis cases in the African Belt countries, 1994-2014 (WHO, 2015)