Reports of cryptosporidium, E. coli and Campylobacter have all increased in Ireland so far this year compared to 2020.

Public health officials said notifications of all three diseases are nationally spread with no clustering pointing to large outbreaks but there are more infections in rural areas.

Since March, cryptosporidium cases are 200 percent greater than for the same period last year. This is on top of the usual seasonal upsurge seen between March and May each year.

The excess in cryptosporidium primarily affects those aged 1 to 19 years old. The Health Protection Surveillance Centre (HPSC) has previously issued a warning and information sheet for parents with advice on hand hygiene.

HPSC data shows there has been 574 cryptosporidiosis cases until May 5 this year compared to 197 in the same period in 2020. This past week 57 infections were recorded with 51 affecting people aged up to 19 years old.

Shiga toxin-producing E. coli (STEC) cases are around 50 percent higher. Since late February, the largest increase is in 1 to 4 year olds.

For STEC, 218 cases have been reported so far this year versus 131 in 2020. This past week saw 28 infections mostly affecting those up to 4 years old followed by people over the age of 65.

Campylobacter rise
Compared to 2018 and 2019, Campylobacter notifications in 2021 are only up slightly on previous years. However, since late February, notifications have been consistently at least 25 percent higher than in any of the past three years and 100 percent higher in children aged 1 to 9.

A total of 847 infections have been reported so far this year compared to 526 in 2020. This past week 65 cases were recorded with 40 affecting those up to 19 years old.

Case control studies have indicated the majority of infections were due to exposure to poultry sources, primarily in the home and associated with handling contaminated poultry meat but not chicken consumption. However, domestic exposure to raw or undercooked chicken is unlikely to explain the recent Campylobacter increase, said officials.

Drinking untreated water, fresh water bathing, playing on beaches and children’s paddling pools were also mentioned. Dining out, use of proton pump inhibitors, eating minced beef and living close to high density poultry operations, particularly after heavy rainfall were other reported risk factors.

Given that the rise in Campylobacter has shadowed that of cryptosporidiosis, experts said it was possible that a similar environmental mode of transmission could explain a proportion of the increase.