Questions

On December 21, the earth is in an equivalent position on the opposite points in its orbit, So the South pole is tipped towards the sun and North pole away from it resulting in 24 hours of darkness at the North pole, as the sun is overhead on the Tropic of Capricorn. This phenomenon is winter solstice; while on June 21, North pole is tipped towards the Sun but the South pole is tipped away from the sun resulting in 24 hours of darkness on the South Pole, as the sun is overhead on the Tropic of Cancer.This phenomenon is summer solstice; while Aphelion is the position of the earth in its orbit when it is at its distant point from the sun.

1) If they use the same cutting board/counter to cut raw chicken, and other foods with out sanitizing in between. 

2) If they have a cold, flu, or pink eye and are handling food, coughing without covering their mouth, then washing their hands.

3) If they don't properly wash their vegetables.

4) Not storing foods at proper temperatures.

And so many other reasons for Food handlers can contaminate food.