Children who received the full programme of vaccines offered free by the HSE to newborns and teenagers are covered against meningitis C.
They are also protected against Hib, a bacterium that can cause a number of serious illnesses, including meningitis.
Since October 2016, another vaccine to protect against meningitis B has been offered to infants.
However, children born before that date did not receive a vaccine to protect them from meningitis B.
They are vulnerable to this B strain of meningitis unless their parents paid to get the vaccine at a cost of €280 privately for them.
Concern has emerged about yet another form of meningitis in recent years - group W meningococcal disease. It is commonly known as men W.
This strain is not yet included in routine HSE jabs offered to children and adolescents.
A MenACWY vaccine is available at €70.