STORY
The number of reported giardiasis cases in England increased by 11.4% during 2025, reaching its highest level for nine years. UK Health Security Agency figures show that 6,069 laboratory confirmed cases were recorded, compared with 5,450 during 2024.
London recorded the largest number of cases with 1,568, followed by the North West with 1,029. Infections peaked during the autumn, with 599 cases reported in October. The UKHSA is investigating the increase and said possible factors include improved testing, greater international travel and environmental or climatic changes.
Giardiasis is caused by the parasite Giardia intestinalis and commonly produces diarrhoea, abdominal cramps, bloating and weight loss. It can spread through contact with infected people or animals and through contaminated food or water. The UKHSA advises people with the infection to remain hydrated, contact their GP and avoid swimming until two weeks after diarrhoea has stopped.