Viruses are much smaller than bacteria, have many different shapes, and contain a nucleic acid core (DNA or RNA) surrounded by a capsid, or protein coating.
- A virus lives and multiplies itself in a host cell.
- First it invades a host cell, multiplies and replicates itself, and then enters the body by destroying the host cell.
- Types of viral diseases include: SARS-CoV-2 (Covid-19), Hepatitis A, B, and C, HIV, Herpes, Measles, the common cold, influenza, and mononucleosis.
- Viruses can mutate.
- There are some vaccines to help prevent the contraction of certain viruses such as Hepatis B and SARS-CoV-2.