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How do antiviral drugs and interferon help fight viral infections?

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Diagram showing the West Nile virus transmission cycle: a mosquito bites an infected bird (the primary reservoir host), then transmits the virus to humans or horses (incidental hosts) through subsequent bites. — infectious disease Birds are the primary reservoirs of West Nile virus. The virus is transmitted to humans and horses by mosquitoes that have bitten infected birds.

Antiviral drugs and interferons combat viral infections through distinct mechanisms, as viruses rely on host cell metabolic functions to replicate.1

Antiviral Drugs

Antiviral drugs are designed to inhibit viral multiplication while minimizing toxicity to the host cell. They target specific stages of the viral life cycle:1
* Enzyme Inhibition: Drugs like neuraminidase inhibitors (e.g., oseltamivir) block enzymes necessary for the release of new viral particles from infected cells. Others, such as reverse transcriptase inhibitors and protease inhibitors, disrupt the replication and assembly of viruses like HIV.123
* Entry Prevention: Some medications, known as fusion inhibitors, block the virus from entering host cells entirely.3
* Uncoating Blockers: Drugs like amantadine prevent the virus from "uncoating" inside the cell, stopping the release of viral genetic material.2

Interferons

Interferons are natural proteins produced by cells in response to viral infections. They act as signaling molecules that:14
* Limit Replication: They trigger the expression of antiviral genes in neighboring cells, making them resistant to infection.4
* Coordinate Immunity: Beyond direct antiviral effects, they enhance immune surveillance by activating macrophages, natural killer cells, and T cells.4