The study of disease transmission is the investigation of how sicknesses spread in populaces in connection to their causal variables. Therefore, the study of disease transmission is to a great extent worried about the assortment and understanding of information about sicknesses in gatherings as opposed to in people. The kinds of information gathered in epidemiological studies give data about the etiology of the illnesses, whether there is a requirement for screening or the presentation of other protection measures and whether medical care offices are fitting.

The predominance of an illness alludes to the extent of individuals in a populace impacted at a particular time. The frequency rate is the quantity of new instances of a sickness in a populace happening inside a predetermined timeframe. Epidemiological investigations can frequently give data about the cause(s) of infections. In this way in the event that an illness has a high occurrence in a specific locale or populace, then, at that point, the sickness might have a hereditary beginning or it could be caused by natural variables unconventional to that area. Epidemiological investigations of transient populaces are particularly helpful since they can give significant data on the etiology of an illness.

A valid example may be where a traveller populace has a high occurrence of a specific sickness and afterward moves to another geological region where the frequency of a similar illnesses low. On the off chance that the occurrence of sickness in the transient populace stays high, all things considered, the sickness has a hereditary premise. If, in any case, the rate in the transient populace diminishes to the level of the new geological area, then natural factors presumably assume a part in its etiology.