Romaine Lettuce and Ecoli
Are you using raw manure that has not been composted in your home garden. Do you make sure that your garden can't be accessed by animals? Both of these reasons could cause Ecoli in home gardens. If your not using raw uncomposted manure and you don't have animals in the garden you should be safe from Ecoli in your home garden.
Here is an article that talks about how to compost properly and to avoid Ecoli in your garden. https://cals.arizona.edu/backyards/sites/cals.arizona.edu.backyards/files/b11summer_pp4-5.pdf
Please let me know if you have any other questions that I can help you with.
Have a wonderful day.