According to the CDC, so far E.Coli has killed one person in the U.S. this year from March 13-April 21. At least 121 people have reported illnesses since the nationwide romaine lettuce recall. These cases are spread out across 25 states including one case in Tennessee.  They all stem from lettuce grown in Yuma, Arizona.

E.Coli lives in all of us but typically does no harm. However, the recent outbreak is due to an unusually potent strain.

"It can cause nausea, vomiting, bloody diarrhea, and can lead to kidney failure," Bev Fulbright, an epidemiology nurse at the Chattanooga-Hamilton County Health Department, said.

Healthy adults often recover from an E.Coli infection within a week, but in some cases, it's been deadly.

Fulbright explained E.Coli is usually caused by careless farming practices.

"The soil can be contaminated, the water used in the fields can be contaminated. There can be animals in the field," Fulbright said.

Staff members at Crabtree Farms on Chattanooga's Southside wash their hands often use clean, naturally filtered well water for irrigation and the few animals they have are kept far away from the crops. Executive Director Sara McIntyre said crops there grow on only 11 acres, three to four of them for lettuces. Being small and local leads to better quality control compared to many large farms containing thousands of acres.

"I can track my lettuces and know exactly when each lettuce is going to be ready. I can watch it week after week after week," McIntyre explained.

The lettuces are washed, packaged and stored immediately after harvesting to further eliminate the risk of contamination.

"You can't have an epidemic when you sell to 300 people and you know them by name," adds McIntyre.

Fulbright said lettuces like romaine are easy targets because they're one of the most popular produce items and are rarely cooked.

No matter where you buy them, follow these easy steps before eating them:

"The best thing to do is to wash your hands well, and then rinse the lettuce under running water and rinse it well," Fulbright urged.

Also, make sure your supermarket romaine wasn't grown in Yuma, Arizona.

The CDC said that from 2010 through the current outbreak, nine outbreaks have been caused by green lettuces or sprouts, compared to 12 from all other food groups including meat, flour and prepared products.