Guidelines for the Early Clinical and Public Health Management of ...

Guidelines for the Early Clinical and Public Health Management of Bacterial Meningitis (including Meningococcal Disease)
Number of BacMen Notifications
600
500
400
300
200
100
0
1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010
Meningo 536 515 330 253 237 198 203 209 179 168 147 114
Other BacMen 51 75 66 47 77 70 68 83 80 87 82 68
CIR Meningo 14.8 13.1 8.4 6.5 6.1 4.7 4.8 4.9 4.2 4.0 3.5 2.7
CIR Other BacMen 1.4 1.9 1.7 1.2 2.0 1.7 1.6 2.0 1.9 2.1 1.9 1.6
Year
16
14
12
10
8
6
4
2
0
Rate per 100,000 total population
Figure 5.2. Number of invasive meningococcal disease and other bacterial notifications in Ireland, 1999-2010
5.5. Invasive Meningococcal Disease (IMD)
5.5.1. IMD cases
The incidence of IMD increased from 12.4 per 100,000 total population in 1997 and 1998 to 14.8 per 100,000 in 1999.
It dropped to 13.1 per 100,000 in 2000 and steadily declined each year after that until it reached 4.7 per 100,000
in 2004. In 2005 and 2006, incidence rates increased very slightly to 4.8 and 4.9 per 100,000, respectively. More
recently in 2010, the incidence rate has fallen further to 2.7 per 100,000 (Figure 5.3).
Between 1999 and 2010, N. meningitidis serogroups B and C accounted for over 96% of all confirmed cases in Ireland
(n=2474/2562) (Table 5.1). Similar to total IMD, the incidence of serogroup B IMD also peaked in 1999 (8.0/100,000
total population). Since then the annual incidence rates have declined somewhat but the magnitude of this decrease
has not been the same as that seen for total IMD. The annual incidence rates of serogroup C disease did not fluctuate
greatly between 1999-2000, with an average annual rate of 3.6 per 100,000 total population reported. However,
since the introduction of the meningococcal group C conjugate (MenC) vaccine in October 2000, the incidence rates
of serogroup C disease have plummeted in Ireland with 0.1 cases per 100,000 total population occurring annually on
average over the last eight years, 2003-2010 (Figure 5.3).
Crude Incidence Rate per 100,000
16
MenC vaccine
introduced
14
12
10
8
6
4
2
0
1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010
Total 14.8 13.1 8.4 6.5 6.1 4.7 4.8 4.9 4.2 4.0 3.5 2.7
Serogroup B 8.1 6.6 6.3 5.1 5.3 3.8 4.0 4.0 3.7 3.5 2.8 2.2
Serogroup C 3.7 3.5 0.9 0.4 0.1 0.1 0.1 0.1 0.0 0.1 0.1 0.1
Year
Figure 5.3. Crude incidence rates of invasive meningococcal disease in Ireland, 1999-2010
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