Since 2015 more cases of invasive meningococcal serogroups W and Y disease have been seen in Ireland. Prior to 2015 the annual number of both serogroups was low. Between 1999 and 2014 there was an average of two cases for both serogroups reported per year.
Between 2015 and 2018, a total of 36 serogroup W and 20 serogroup Y cases were reported, giving an average annual notification rate 9 cases per year of serogroup W and for 5 cases per year of serogroup Y. See Figure 1.
(Data from HPSC 27/06/2019)
There were increasing cases of Men W disease in several European countries e.g. UK and the Netherlands in recent years before the pandemic. In view of the emergence of meningococcal serogroups W and Y, the National Immunisation Advisory Committee (NIAC) recommended that one dose of MenACWY vaccine should be given to all students in 1st year of second level education replacing the MenC vaccine in 2019. All students will now receive the Men ACWY vaccine instead of the Men C booster vaccine that has been given in 1st year of second level school since 2014. The Men ACWY vaccine boosts protection against Men C disease as well as giving protection against N. meningitidis Groups A, W and Y invasive disease.
Meningococcal disease is a serious and sometimes fatal illness which can cause meningitis and septicaemia.
Around 10% of those affected will die, for those who survive; many are left with long term sequelae including brain injury or loss of memory, deafness or blindness, and loss of limbs.
Meningococcal disease may occur at any age but the highest rate of disease occurs in children under 5 years of age. There is a second peak of cases in young people aged 15 to 19 years.
Adolescents are also known to have the highest rates of carriage of meningococcal bacteria. As well as providing direct protection, the Men ACWY vaccine prevents carriage of the bacteria and so will also provide some protection to other age groups through herd immunity.