HIV (Human Immunodeficiency Virus) is a communicable viral disease. How is the HIV virus primarily transmitted from one person to another? Select one option:
The table below shows the annual number of new HIV diagnoses recorded in a specific urban clinic.
| Year | Number of new HIV diagnoses |
|---|---|
| 2014 | 1200 |
| 2017 | 1550 |
| 2020 | 450 |
Describe what happened to the number of new HIV diagnoses from 2014 to 2020.
What could cause a significant decrease in the number of new HIV transmissions in the future? Select one option:
Vaccines can be developed to prevent the spread of viral pathogens. The statements below outline the sequential stages of how a vaccine stimulates active immunity in a person.
Write the stages A, B, C, and D in the correct sequence to show how vaccination works. The first stage has been completed for you:
C→‾→‾→‾\text{C} \rightarrow \underline{\quad\quad} \rightarrow \underline{\quad\quad} \rightarrow \underline{\quad\quad}C→→→
Before any new antiviral drug or vaccine is approved for clinical trials on humans, it must undergo preclinical testing. After testing on laboratory-grown human cells and tissues is complete, what is the next stage of preclinical testing? Select one option:
Many modern drugs are synthesized by chemists but were originally discovered in plants or microorganisms. Match each medicine to the correct source from which it was originally derived:
Sources: