Human population growth serves as an important model for population ecologists, and is one of the most important environmental issues of the twenty-first century.
Confidence votes 1. no not all, blood-borne pathogens are typically found in the blood stream and any bodily fluid that can contain blood can contain a blood borne pathogen. these include urine, feces, saliva, sperm, vaginal secretions, and even tears.
1 Through Body Fluids: Pathogen can infect you by entering your body through semen and blood. Some of the most common examples of pathogens that spread through body fluids are hepatitis and HIV viruses.  Vectors: It's an animal that spreads disease-causing pathogens from one host to another.