Although increasing numbers of malaria cases have been reported in Ireland in recent years, disease rates for Northern Ireland and the United Kingdom as a whole have actually declined. [1,2]

References:
1. Berger SA. Infectious Diseases of Ireland and Northern Ireland, 2010. Gideon e-book series, 437 pp. http://www.gideononline.com/ebooks/country/infectious-diseases-of-ireland-and-northern-ireland/
2. Berger SA. Malaria: Global Status, 2010. Gideon e-boon series, 378 pp. http://www.gideononline.com/ebooks/disease/malaria-global-status/

A recent death in Ireland highlights the fact that the incidence of leptospirosis in this country has been increasing in recent years. In fact, during the past decade, leptospirosis rates have expanded well beyond those of those of the United Kingdom, including those for adjoining Northern Ireland. See graph:

Update: Published in ProMED

Another post in ProMED from Steve describing Cryptosporidiosis in Ireland with a graph comparing rates in neighboring regions:

Background data:
Rates of Cryptosporiosis in Ireland and adjacent countries have been similar since the 1980′s.

Cryptosporidiosis became a notifiable disease in Ireland in January 2004, with 61 percent of cases having been reported during April to June [?2004]. A total of 5 outbreaks (25 outbreak cases) was reported in 2004. A total of 6 outbreaks (49 outbreak cases) was reported in 2005.

Prevalence surveys:
4 percent of gastroenteritis among children.
4 percent of diarrhea requiring hospitalization among Dublin Children 1987.
149 cases were reported among children below age 2 years in 2002; 106 in 2003.
64 patients were hospitalized for cryptosporidiosis in 1999; 57 in 2000; 65 in
2001; 53 in 2002. 70 cases (18 per 100 000) were reported by the South-Eastern Health Board in 2001. 66 cases (19 per 100 000) were reported by the Western Health Board in 2001.

Infected local shellfish species:
_Mytilus edulis_ (Common mussel) in the Sligo Area
_Dreissena polymorpha_ (Zebra mussel) in the Shannon River drainage area.

Notable outbreaks:
2002 – Outbreaks (3 outbreaks, 65 cases) were reported, including a water-borne outbreak more than 32 cases) in the Midland region.
2005 – An outbreak (31 cases) in the western region was associated with contaminated water.
2007 – An outbreak (125 cases) was reported in Galway.

Northern Ireland:
Notable outbreaks:
2000 – An outbreak (121 confirmed cases) was reported – with most cases in the County Antrim and County Down towns of Lisburn and Bangor.
2001 – An outbreak (230 confirmed cases) was reported in Belfast – source unknown.
2001 – An outbreak (57 cases) was reported in Ulster – source unknown.
2001 – An outbreak (110 cases) was reported in Eastern Health Board – ascribed to contamination of water from the Dunmore treatment facility.
2003 – An outbreak (391 cases) was reported among British tourists at a hotel in Majorca – 179 from England and Wales, 170 from Scotland and 42 from Northern Ireland.
2004 – An outbreak (14 cases) was reported in the Midland Health Board – ascribed to a contaminated water supply.