Hi, I Just Ate A Salad With Romaine Lettuce -

Hi, I just ate a salad with Romaine Lettuce - when I was done eating I read a newly published article about how there is a problem with E.Coli and romaine lettuce throughout the USA. - Can I be treated prior to symptoms showing up? I feel fine, but as I understand it it could be 3-4 days before I feel sick (if i was infected). Is there anyway to prevent the illness?