E coli and salmonella are both types of bacteria that can flourish in some foods, such as undercooked hamburger meat or unpasteurized fruit juice. They give off harmful toxins that can kill human cells and cause illness.

Unlike bacteria, viruses are not cells; they consist of DNA molecules, containing the virus's genes surrounded by a protein coat. A virus can attach itself to cells and either inject molecules into the cell, or the cell may absorb it. Once inside, the molecules cause the infected cell to make new viruses that can spread to other cells.
Chlorine dioxide is an antimicrobial pesticide commonly used for water purification, washing fruits and vegetables, disinfecting meat, poultry and food processing equipment, and treating medical waste, among other uses. It fights harmful bacteria by damaging the cell membrane so that vital nutrients can't be distributed throughout the cell. It combats potentially deadly viruses by bursting them like a little nuclear bomb.
Chlorine dioxide is a yellow-green or orange gas, and is highly sensitive to ultraviolet light, temperature and pressure. But it has been shown to be much more effective in combating microbes than many of its forerunners.
It is very easy for one person to pass on germs to others. "Typhoid Mary" was an Irish cook who worked for a family in New York City at the turn of the 19th century. She didn't know it, but she was a carrier for a type of salmonella bacteria. She spread the germ into the food she prepared, and the entire family came down with typhoid fever.
