Which statement correctly describes communicable diseases?

Which statement correctly describes communicable diseases?

• A. They can be transmitted from one host to another
• B. They cannot be transmitted
• C. They are always non-infectious
• D. They are always cured by vaccination

Answer: (A)

Communicable diseases are defined by their ability to spread from one person to another. This transmission can happen in many ways—through direct contact, droplets, airborne routes, contaminated food or water, or via vectors like mosquitoes—so outbreaks occur when the pathogen moves between hosts. That makes the statement true: these diseases can be transmitted from one host to another. The other options aren’t correct because some communicable diseases can indeed be transmitted; saying they cannot be transmitted is false. They are not always non-infectious is false because infectiousness is what makes a disease communicable. They are always cured by vaccination is false because vaccines prevent disease or reduce severity and transmission, but they don’t cure an illness once someone is already infected, and not every disease has a vaccine.

Communicable diseases are defined by their ability to spread from one person to another. This transmission can happen in many ways—through direct contact, droplets, airborne routes, contaminated food or water, or via vectors like mosquitoes—so outbreaks occur when the pathogen moves between hosts. That makes the statement true: these diseases can be transmitted from one host to another. The other options aren’t correct because some communicable diseases can indeed be transmitted; saying they cannot be transmitted is false. They are not always non-infectious is false because infectiousness is what makes a disease communicable. They are always cured by vaccination is false because vaccines prevent disease or reduce severity and transmission, but they don’t cure an illness once someone is already infected, and not every disease has a vaccine.