The HSE dealt with 4,000 callouts to rat infestations across Dublin in the past year alone.
Figures obtained by the Herald show almost 60 per cent, or 2332 of those pest control complaints were in the northside.
The other 1,611 complaints were for south Dublin, where the HSE had to appoint an extra three members of staff to its pest control service.
That brought the number up to five. In north Dublin, six people are employed in the pest control service.
A spokesperson for the HSE said the main reason for callouts is sightings of rats and the associated public health concerns. They're encouraging Dublin homeowners to take the necessary steps to prevent infestations.