What is an infection and how can it be transmitted?

Infection occurs when foreign microorganisms enter the body. Most often these are viruses. Bacterial infections are less common. Even less common are fungal infections and diseases caused by microorganisms. In order for the infectious process in the body to begin to develop, it is necessary that the microorganism gets through the entrance gate in sufficient quantities. Entrance gates can be: damaged and intact skin, oral cavity and gastrointestinal system, nasal cavity and respiratory system.