Three years after exposure to a virulent form of the flu, a ...

[bcretired]

Three years after exposure to a virulent form of the flu, a population faces the same flu strain. The public health department recognizes that there are members of the population who have not been exposed to the flu strain. Which is most likely to happen?
 
  A) The unexposed population will contract the illness
  B) The unexposed population is not likely to contract the illness
  C) The unexposed population will contract the illness and reinfect others
  D) The flu will reach epidemic proportions and both populations will become ill

Question 2

Nursing students in an enclosed classroom begin to become ill with a gastrointestinal illness. The public health department identifies this occurrence as an emerging epidemic and isolates the population that is ill.
 
  According to microbial adaptation, those who survive the illness will then do which of the following?
  A) Recover with adaptive organism reintroduction into the environment
  B) Develop improved defenses against reinfection
  C) Become hosts to the organism, which is symbiotic in nature
  D) Become carriers of the infection, ultimately leading to an epidemic

[morganmarie791]

Answer to Question 1

Ans: B
Feedback:
If a substantial proportion of people in a population are not susceptible to a communicable disease, the few people who are susceptible are not likely to be exposed and contract the illness. This is a process called herd immunity.

Answer to Question 2

Ans: B
Feedback:
Three stages of microbial adaptation and change occur over varying periods of time. During stage I, an epidemic occurs. The microbes enter a virgin population where hosts have no prior exposure to the organism and have few defenses. This leads to further spread in the population. Ultimately, survivors are usually left with improved defenses against reinfection. During stage II, the infection becomes endemic or continuously present in a geographic area or population of people. Routine childhood diseases are an example of such infections. During stage III, symbiosis is possible. Further adaptation occurs, resulting in mutual tolerance and sometimes mutual benefit for both the microorganism and the host. This is the preferred outcome.

[bcretired]

Gracias!

[Liddy]

Excellent