Health chiefs fear the fact hundreds of thousands of people from around the world will all be in one place this summer would increase the likelihood of contagious bugs or even new strains spreading.
Monitoring systems will be expanded in the run up to and during the Games to ensure any virus is picked up on early.
Security experts also have great faith in the British weather after warning the greatest climatic threat to visitors will be suffering from a heatwave.
The warnings are included in a Home Office risk assessment which puts “natural events” alongside terrorism, organised crime, extremism and public disorder as the main threats.
Under human diseases, it warns: “The likelihood of a new, or newly recognised, infectious disease spreading to the UK is low but, with large numbers of visitors entering the UK at that time, we will need to be alert to these and to the more likely, but less serious, risk of a food borne illness or gastroenterinal outbreak such as norovirus.” Read More