Question

Disease transmission is a really important topic in the subfield of disease ecology. How is the parasite transmission term modeled in the differential equations we discussed in lecture (i.e., the equations that describe the changes in the susceptible, infected, and recovered classes of hosts)?
Differentiate between the different types of horizontal transmission. How does the basic reproductive number (R0) differ from the transmission term? I’d like you to explain this with words, not with a mathematical model.]

Answer 1

Types of horizotal transmission: Two types of horizontal transmission as given below:

(1)  Direct transmission: In this case, transmission occurs from diseased person to healthy person directly by touch, through air, through water or through articles used by diseased person.For example, common cold, tuberculosis, measles.

(2) Indirect transmission: In this case,  transmission occurs when pathogen are transfered from diseased person to healthy person through an intermediate organism called vector who carries the pathogen. For example, malaria, dengu etc.

Basic reproductive number: The basic reproduction number (R0) is a number used to measure the transmission potential of a disease. It is the average number of production pf secondary infections by a typical case of an infection in a population. For example, if the R0 for any infectious disease in a population is 15, then, each new case will produce 15 new secondary cases.