Virus Nomenclature and Taxonomy

What was the primary aim of the International Committee on the Taxonomy of Viruses (ICTV)?

Which of the following is NOT a phenotypic characteristic considered in the ICTV classification?

Which classification system was developed by David Baltimore?

How many realms and kingdoms are recognized in the ICTV classification as of 2020?

Which of the following is a genotypic characteristic considered for virus classification?

What is one reason viruses are named based on their host organisms?

Which of the following is NOT a method of naming viruses mentioned?

What was one consequence of the lack of a consistent naming system for viruses by the 1960s?

Which of the following methods is NOT part of the taxonomy for viruses?

What does the term 'cytopathology' refer to in the context of virus naming?

Why might a virus be named based on the way people believed it was contracted?

Which of the following is an example of a virus named after a specific disease?

What is a major challenge in the classification of viruses?

Virus Nomenclature

Historically inconsistent, viruses were named based on:
- Host organism
- Geographic location of isolation
- Discoverer
- Disease caused
- Body site of isolation
- Perceived method of contraction
- Cytopathology during infection
- Combination of these factors

Virus Taxonomy

Two main methods for classifying viruses:
- International Committee on Taxonomy of Viruses (ICTV): Established in 1966, originally focused on naming, rebranded in 1971.
- Baltimore System of Virus Classification: Developed by Nobel Prize winner (1975) David Baltimore

ICTV Classification Criteria

Aims to create a universal taxonomy for viruses affecting plants, animals, and bacteria.
Focuses on characteristics that differentiate viruses:
- Phenotypic:
  - Genome composition
  - Virion/capsid structure
  - Presence of an envelope
  - Host range
  - Pathogenicity
- Genotypic:
  - Sequence similarity
  - Gene content
  - Gene synteny (order)
  - Gene expression system
  - Phylogenetic relationships

Monkeypox Virus Classification Example

Phenotypic characteristics used in classification:
- Natural host ranges (determining subfamily)
- How the virus grows and affects cells
- Plague characteristics (morphology of pocks)
- Disease characteristics (mortality and morbidity)
- Serological criteria (neutralization tests, cross-protection in animals)
Genotypic characteristics used:
- Amino acid sequence identity (in hemagglutinin or A-type inclusion protein)
- Nucleotide sequence identity (between different species)

Explore the historical methods of naming viruses and the current classification systems used today. This quiz covers the ICTV criteria, the Baltimore classification, and the characteristics that differentiate various viruses. Test your knowledge on virus taxonomy and nomenclature principles.