Reports of Cryptosporidium, Escherichia coli, and Campylobacter are on the rise in Ireland this year as compared to 2020. 

According to public health officials, all three diseases are nationally spread with no clustering, pointing to large outbreaks, but infections in rural areas have increased.

Since March 2021, Cryptosporidium cases are 200 percent greater than for the same period in 2020. This is on top of the usual seasonal upsurge that is seen between March through May each year. 

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

Until May 5, 2021, there were 574 cryptosporidiosis cases reported, according to HPSC data, compared to 197 in the same period in 2020. 

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

In the case of STEC, 218 cases have been reported so far in 2021 versus 131 in 2020. 

When comparing 2018 and 2019 to 2021, Campylobacter cases in 2021 are only up slightly. However, since late February 2021, cases have been consistently at least 25 percent higher than in any of the past three years and 100 percent higher in children ages 1 to 9. 

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

Also mentioned were drinking untreated water, fresh water bathing, and playing on beaches and in children's pools. Other reported risk factors including dining out, use of proton pump inhibitors, eating minced beef, and living close to high density poultry operations, particularly after heavy rainfall.

Because the rise in Campylobacter has shadowed that of cryptosporidiosis, experts say it's possible that a similar environmental mode of transmission could explain some of the increases.