Explain the statement by giving two examples: ‘It is not necessary that the pathogen may affect an organ or tissue depending upon the point of entry.’
The pathogen does not necessarily affect an organ or tissue depending on the point of entry. It may invade the body at the easiest accessible route and then makes it’s way to the target organ/tissue. The examples of such instances are:
(i) AIDS causing virus - enter through sex organs but spread to lymph nodes all over the body.
(ii) Japanese encephalitis - virus enter blood through mosquito bite but reaches brain.
(iii) Malaria - protozoan plasmodium enter blood through mosquito bite but reaches liver and then passes into the RBC. (Any two)