can someone help me better understand this sentence please, I am clueless and trying to study for a exam?

Question

The potential for micro-organisms to cause disease depends on the number of organisms, virulence, ability to enter and survive in a host and susceptibility of the host. Potter and Perry 3rd edition.

thank you for taking the time to help me out.

Answer 1

Basically, the sentence is stating 4 separate things:

1- That the potential of a disease causing organism to inhabit a host is influenced by the number of organisms present upon the initial infection of the host. Essentially, that a larger initial infection is more difficult for an immune system to combat than a small initial infection.

2- That its potential to inhabit a host is influenced by the virulence of the invading organism.
Some "bugs" are nastier than others.... Certain organisms are more capable of resisting a hosts immune response than others.

3- That its potential to inhabit a host is influenced by its initial ability to actually enter the host organism.
Some pathogens are capable of airborne transmission, others require direct contact with a mucous membrane or an open sore to enter a host organism.

4- That its potential to inhabit a host is influenced by the hosts own susceptibility to infection.
A given host may have already been exposed to the pathogen in question and be better able to respond to a potential infection (such as someone who has already had chicken pox vs someone that hasn't yet had it). Or a specific host may have a natural immunity to certain pathogens that others around it don't posses

Answer 2

Disease causing micro-organisms depend of 4 things:
1. The number of the organisms...the more the bacteria, the more the infection or the worse the infection is.
2. The nastiness of these bacteria.
3. The bacteria's ability to enter its host...whether it's a lung, a bladder, a genital area..etc.
4. How susceptible the host is or how vulnerable the host is to these bacteria.
Plain and simple for you....
Thanks for letting me help.

Answer 3

Well if the number of micro-organisms is small then the human immunity will control that but if they are too many then they will fight even if your white blood cell produces antibodies.When it means susceptibility it means if the person(the host) affected is weak or healthy enough to stop the distribution of the disease in the body.

Answer 4

the possibility of a bacteria or virus to cause sickness in a person or animal is directly proportional to the number of bacteria present in the person or animal, its ability or disease causing strengths, an entrance into the person or animal through such things as a wound or by entering on or in food, or other source, the absence in the person or animal of antibodies that are designed to fight that particular bacteria or virus.and the strength and good health of the person or animal which affects that persons or animals ability to fight off the disease bearing bacteria or visus.