Virus is non living outside the body. They contain genome DNA or RNA but cannot grow independently. Instead, they must need a host organism for its survival as they use genetic instructions of host organism. Therefore, they can only reproduce in host cells.
When virus enters the body, it must be in active or in latent stage.
Hidden or latent virus is a virus that inserts its genetic material inside the cell but hides itself in unfavourable conditions and when conditions are favorable it becomes active and controls host cell functions that helps to make copies of virus genetic material. Then it assembled into new viruses. But if conditions become unfavorable they again hidden themselves.
Active viruse means virus that infects host cell when it injects the genetic material into the cell. It controls the cells functions and make copies of genetic material. Then it assembled into new viruses and repeat the process.
1. Virus enters the cell by using its surface proteins.
2. The inserts its genetic material into the cell. The genetic material can be latent or active. Latent means it becomes a part of the cell and waits for favourable conditions such as stress. Active which means infects the cell immediately.
3. When a virus infects the cell then its genetic material enter the nucleus and instructs the cell to make copies of its genetic material and proteins.
4. Then it assembled into new viruses and burst out of the cell. This process then repeated on to other cells.