North West is second-worst hit area for this stomach bug - here's what to do
Parents should contact their GP or NHS 111 if they or their children are ill with dehydration, or if diarrhoea worsens or lasts longer than three days.
New data shows a rise in cases of Giardia - with the North West the second-worst hit area of the UK.
Giardia is a gastrointestinal illness, caused by a parasite called Giardia intestinalis. The most common symptom is diarrhoea, which is often accompanied by abdominal cramps, bloating, burping, wind and weight loss. If left untreated, in rare cases, children can experience significant weight loss, malnutrition and stunted growth.
The number of giardiasis cases in England rose from 5,450 in 2024 to 6,069 in 2025. This is an increase of 11.4 per cent, and is the highest number of cases reported since 2016. London reported the highest number of cases (1,568), following by North West (1,029). Cases peaked in autumn, with the highest number of reports in October (599 cases), followed by September (580 cases) and November (574 cases).
The number of laboratory-confirmed cases reported each year returned to pre-pandemic levels in 2023 and has risen since. The UKHSA (UK Health Security Agency) is investigating the reasons for this, but say it is possibly due to a mix of factors, including new and more effective testing, increased travel since the pandemic and climate and environmental changes.
How do you get it and how is it spread?
Giardia infection can be acquired in the UK as well as during international travel. It spreads through direct contact with infected people or animals, or by swallowing contaminated food or water. The infection can also be sexually transmitted. Infections are also seen in returning travellers from Southern Asia, South-Eastern Asia, Africa and South America.
International travellers should take precautions when travelling abroad to reduce the risk of infection. This includes drinking bottled water rather than tap water and consuming cooked food rather than raw items such as salad vegetables washed in tap water.
Further advice on avoiding food and water borne diseases can be found on TravelHealthPro: NaTHNaC - Food and water hygiene.
Additionally, travellers should be careful when swimming, for example in rivers, lakes, the sea or during open-water swimming events, where water may be contaminated. Treatment includes maintaining hydration (drinking plenty of water) and antibiotics.
Tips
Nicola Love, Senior Food Safety Surveillance Lead at UKHSA, said: “We are seeing a rise in giardiasis in the UK. Symptoms can last from weeks to several months and if left untreated, it can cause serious complications especially in young children, the elderly and those with weakened immune systems.
“There are some simple precautions everyone can take to reduce their risk, whether you are planning an autumn getaway somewhere warm or staying in the UK.
“Good hygiene can help prevent giardiasis and other common gastro illnesses. Wash your hands with soap and water after using the toilet, after changing nappies, and before preparing food. Encourage children to wash their hands regularly too.”
What to do
If you have a Giardia infection, continue to hydrate yourself and see your GP, do not go swimming until two weeks after your diarrhoea has stopped. Parents should contact their GP or NHS 111 if they or their children are ill with dehydration, or if diarrhoea worsens or lasts longer than three days.