The latest figures from the HSE's Health Protection Surveillance Centre show it was notified of 23 meningococcal cases between December 24, 2018 and January 29, 2019.
It represents an increase of two more than the 21 cases which were notified to the HPSC in the same period last year.
Four of the 23 patients who had bacterial meningitis died following their illness, while patients in varying age groups were affected.
The HSE said it was not an outbreak but reflected a known increase seen in the winter and spring seasons.
In total, there were 89 cases identified in 2018 and 76 in 2017. Meningitis can affect any age group with symptoms including fever, headache, vomiting, diarrhoea, muscle pain and stomach cramps.
The HSE advises parents to have their children vaccinated as per the Primary Childhood Immunisation Programme and to be aware of the symptoms.
Separately, 14 cases of viral meningitis has been notified to the HPSC with no deaths reported.