No Cow Tea for Me!

My 91 year old neighbor Mario, who passed away last year, gardened all of his life, and I must admit his vegetables looked great. Early in the spring Mario would go to the dairy farm a mile or so from our houses, and get a five gallon bucket of manure. (A nice word for cow feces)
He would put several inches of water on top of the manure, cover the bucket, and place it in the sun behind his garage. Each day he would ladle off some of the concentrated "tea" , add some water, and pour this mixture over his lettuce.
Mario would, of course, rinse the lettuce before tossing it into his salad, but to my way of thinking no amount of washing would remove weeks and weeks of cow tea residue.
I used to envy Mario's ability to grow vegetables, however, since I began using hydroponic gardening techniques my results are far far superior to Mario's cow tea lettuce. Also, I have never grown lettuce in a conventional garden that I did not have to contend with zillions of aphids. Mario was using a powered pesticide for aphid control, but I would have given odds that the cow tea alone would kill aphids. Between the cow tea, aphids, and pesticide, the flora and fauna in his digestive system was most likely unusual to say the least. As he made it until past ninety, I guess his system adjusted reasonably well to his gourmet habits.
Recently, for the first time in almost ten years, I was sick for almost two days. My wife also came down with the same symptoms of nausea and vomiting. I am a vegetarian and she is not, but we did share a salad the evening before. It was bagged spring mix lettuce. My guess is that we both had a case of Escherichia coli . And we all know that commercial growers use their own version of "cow tea". So, no more cow tea for me!!