What are the importance of the Parenteral route?

The parenteral route of infection occurs when an organism gets access to the tissues underneath the mucous membranes or the skin. Punctures, injections, bites, cuts, wounds, surgery and split skin or mucous membranes (from swelling or dryness) are all examples of parenteral routes of infection.

Source:

Tortura, Funke, Case. Microbiology: an Introduction, 10th ed. San Francisco: Pearson: 2010: 429.