7.8: Direct person-to-person transmission of pathogens
selected template will load here
This action is not available.
A new infection begins when pathogens leave the body of their host – the infected individual in which the pathogens are multiplying – and enter a new host. They may be repelled by defense mechanisms (i.e. skin) in the new host, or they may survive and reproduce in sufficient numbers to cause an infectious disease.
Transmission of pathogens can occur directly between people, or indirectly in the air, water or food, or via other animals to humans, or from sources in the environment. In this section we explore direct transmission.
Figure \(\PageIndex{1}\). Direct person-to-person transmission of infection. (a) Contagion and sexual transmission. (b) Mother-to-child transmission.
Figure \(\PageIndex{1}\) represents the three ways in which pathogens can be transmitted by direct person-to-person contact. They are: