Medicine & Health
What is A virus?
A virus is a tiny infectious agent — far smaller than a cell — that can only reproduce by hijacking the cells of a living host. It's essentially genetic material (DNA or RNA) wrapped in a protein coat.
See it, don’t just read it.
Watch a 2-minute lesson with voice + animation that explains a virus.
Key things to understand
- 1Viruses aren't fully 'alive' — they can't reproduce on their own.
- 2They invade a host cell and force it to make copies of the virus.
- 3They cause diseases like the cold, flu, COVID-19, and measles.
- 4Antibiotics don't work on viruses; vaccines help prevent them.
Frequently asked questions
- Are viruses alive?
- They're in a grey zone — they have genes but can't reproduce or function without hijacking a living cell.
- How do viruses make you sick?
- They invade cells and force them to produce more viruses, damaging tissue and triggering immune responses.
- Why don't antibiotics work on viruses?
- Antibiotics target bacterial processes that viruses don't have; antivirals and vaccines are used instead.