According to the data, claims peak between July and September, reflecting the higher number of travellers as people embark on their summer holidays. However, claims can also be costly, with Aviva data showing that treatment for stomach-related issues costs £4,095 on average. Despite Spain having the highest number of stomach-related claims overall, the USA is the most expensive country to seek treatment, where medical costs for stomach bugs can reach £11,881 on average. In the USA, medical costs for gastro-related illnesses can reach over £10,000, meaning travellers without insurance could face hefty medical bills. Aviva travel claims data 2025 relating to food poisoning or gastroenteritis [↑]*****Notes