Firstly, ringworm is not a worm but a fungal infection of the skin found in all animals and humans if the spores are contracted from an outside source such as straw.
Cystircercus is the prescence of tape worm eggs in meat, they are large and easily seen, meat inspectors at registered abattoirs are trained to locate these and detain the meat for veterinary inspection and possible condemnation. These eggs can be destroyed by freezing or cooking the meat through. There is a chance of contracting salmonella, e-coli, mould toxins are just a few infections found in vegitables, but we cannot be scared into not eating, if you buy food from sources where no health inspections take place, just cook everything well, and any bacteria or parasites will be destroyed, I lived most of my life in remote parts of Africa and never contracted any diseases, just by washing fruit and raw vegitables well, and cooked all meat and other vegitables well enough to make them safe!! Eat what you enjoy and ignor those with their own self-serving agendas.