Final answer:
The microorganism that is not living, causes quick and highly contagious illnesses, and does not grow in food is a virus.
Step-by-step explanation:
The type of microorganism described in the question is a virus. Viruses are known for causing illnesses that can come on quickly and be highly contagious, such as colds and the flu. Unlike bacteria, fungi, and parasites, viruses are not living organisms and cannot grow or reproduce outside of a living host. Furthermore, they do not grow in food. Antibiotics are effective against bacteria but do not work on viruses. However, there are antiviral drugs that can treat many diseases caused by viruses.