VIRUS IN FOOD

What a virus is… and isn’t

  • Virus is not a cell: No nucleus, cell membrane, ribosome, mitochondria, etc.

  • Virus is very small: A period (.) could contain 3000 polo viruses

  • Virus is not complex: They have only 5 genes

  • The purpose of study: make use of the good side of microbiology, and avoid the downside

  • Viruses are small acellular entity/particle

  • Size of diameters: 15 to 400 nanometers (0.015 to 0.4 micrometers)

  • Contamination of foods are usually from food-handlers. Contamination degree can be variable even in identical product

The primary symptoms of viral foodborne diseases

  • Only a few particles are necessary for the disease to develop

  • High numbers of viral particles are further transmitted via faeces of infected people resistant outside host cells (up to 1011 particles/gram of faeces in members of genus Rotavirus)

  • Specific living cells are necessary for virus replication; accordingly they cannot multiply in foods or water

  • Foodborne viruses are relatively stable and acid-resistant

Contamination may occur trough

  • Contact with human or animal faeces, or contaminated water

Viral structure

  • Nucleic acid: DNA or RNA, not both

  • Protein coat (capsid): Protect nucleic acid from environment

  • Envelope: Only in animal infectious viruses, spike-like projections that recognize animal cells

Viral replication

  • they don't reproduce, they replicate

  • Viruses cannot replicate on their own

  • Host cells

  • Lytic cycle: when a virus enter a cell, they immediately begins to replicate, rapidly killing the cell

  • Lysogenic cycle:

Virus adalah parasit berukuran miskrokopis yang menginfeksi sel organisme biologis

Struktur Virus

  • Virus tidak memiliki sel (aseluler)

  • ukurannya 20 mμ - Z mμ

  • Hanya bisa dilihat oleh mikroskop