Exam question 1 - Plain language

Question 1

You are involved in a small working group reviewing services for people living with HIV/AIDS.
1. Explain to the lay members of the group the meaning of the terms
incidence and prevalence and their different uses in public health.

Answer 1

Meaning of terms:
* Incidence
o # people in specific population newly diagnosed with the disease
o over a given period of time
o measure of rate of occurrence

• Prevalence
  o total # people with diagnosed disease in the population
  o usually at a point in time
  o shows proportion in population that are living with disease

Uses in public health:
* Incidence
o used to see the pattern of occurrence of disease
o indicates changes in transmission/development of condition
o important to detect if control/preventative strategies are effective
* Prevalence
o Important to demonstrate disease burden in population
o Used to predict demand for healthcare services

Question 2

You are involved in a small working group reviewing services for people living with HIV/AIDS.
2. Explain why the prevalence of HIV infection is increasing, although the
incidence of HIV infection is generally static or declining.

Answer 2

• Incidence decreasing due to effective preventative strategies:
  o promotion of safe sex/effective prophylaxis/change in behaviour
  o also possible, decrease in diagnosis due to poor access to testing
• Prevalence increasing due to better treatment/prognosis
  o better life expectancy with HIV
  o greater proportion of people in population living with HIV