if you use scan as you shop you need to have a tesco club card and you can put in bags as you go so only you touch your shopping.
You still won't know how many others customers might have touched/picked up the item before you though. @MaNaAk to help put your mind at rest, the world health organisation has advised that there have been no confirmed cases of covid transmission through food or food packaging. As with anything, frequent hand washing will help to stop transmission so it is recommended that hands should be properly washed after handling food packages and before eating. Also use hand sanitiser when entering the shop, wash your hands thoroughly afterwards, and also after handling/storing purchased products. It's also worth keeping shopping to a minimum - I just go food shopping once a week now to reduce the risks:
https://www.bbc.co.uk/news/explaine...nization says,through food or food packaging"