Viral Infections

Viruses

  • Need a host to reproduce

  • Some can be prevented by vaccine

  • Spread by direct contact, ingestion of contaminated food or water, inhalation of airborne particles, exposure to contaminated body fluids or equipment

  • Antiviral Drug is one that is formulated to seek out a virus and prevent its replication in body fluids or in host cells without interfering with normal cell function

  1. Influenza virus becomes attached to a epithelial cell

  2. The cell engulfs the virus by endocytes

  3. Viral contents are relased. Viral RNA enters the nucleus where it is replicated by the viral RNA polymerase.

  4. Viral mRNA is used to make viral proteins

  5. New viral particles are made and released into the extracellular fluid. The cell, which is not killed in the process, continues to make new virus

Virus Life Cycle

It is important to note that viruses cannot replicate outside of a cell. Below is how viruses invade and cause harm:

  1. Attach, the virus must attach to the host cell

  2. Enter, the virus must then invade the host cell

  3. Uncoat, the virus must shed the outer coating that enabled it to invade the cell

  4. Replicate, the virus must make a copy of its genetic material

  5. Assemble, new viral particles are constructed

  6. Release, these new particles leave the host cell to invade other cells, by breaching the cell wall, the host cell is compromised and dies

Antiviral drugs work by targeting the pathogen at any point in the virus life cycle in order to arrest the activity. However, this does come with risk. Developing new antivirals is cautionary as there must be a balance between interfering with the virus’ intrsion while not doing any harm to the host organism’s cells.

Antiviral

Antiviral drugs are a class of medication use specifically for treating viral infections rather than bacterial ones. Unlike most antiobiotics, antiviral drugs do not destroy their target pathogen; instead they inhibit their development.

Viruses cannot reproduce on their own, and instead reproduce by invading a host cell using its machinery to make copies of themselves.

Treat viral infections:

  • Influenza

  • Colds

  • Polio

  • Mumps

  • Herpes simplex

  • Measles

  • Chicken pox

  • Shingles

  • Hepatitis

  • HIV