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FURTHER LABORATORY STUDIES ON THE CLASSIFICATION OF PSITTACOSIS-LIKE AGENTS

M D Beck1, M D Eaton, R O'Donnell

  • 1Research Laboratory of the California State Department of Public Health, Berkeley.

The Journal of Experimental Medicine
|October 30, 2009
PubMed

Insights

This study reveals significant variations among psittacosis-like viruses, differentiating them into three distinct groups: psittacosis, ornithosis, and human pneumonitis. These findings aid in classifying atypical pneumonia-causing agents.

Area of Science:

  • Virology
  • Pathogen Classification
  • Infectious Diseases

Background:

  • Psittacosis-like viruses cause atypical pneumonia in humans.
  • Variations among these viruses have been observed.
  • Previous classifications may not fully capture the diversity of these agents.

Purpose of the Study:

  • To investigate and classify variations within a group of psittacosis-like viruses.
  • To differentiate between distinct viral strains based on pathogenicity and immunity.
  • To establish a refined classification for viruses implicated in atypical pneumonia.

Main Methods:

  • Pathogenicity and latency tests were conducted in mammalian and avian models.
  • Active cross-immunity tests were performed to assess viral relationships.
  • Comparative analysis of viral characteristics was undertaken.

Main Results:

  • Significant variations were identified among the tested psittacosis-like viruses.
  • Pathogenicity, latency, and cross-immunity tests confirmed these differences.
  • The viruses could be distinguished based on their biological properties.

Conclusions:

  • The psittacosis-like viruses causing atypical pneumonia in humans can be classified into three distinct groups: psittacosis, ornithosis, and human pneumonitis (strain S-F).
  • This classification is supported by experimental evidence from pathogenicity, latency, and cross-immunity studies.
  • Further research into the undetermined origin of the human pneumonitis strain is warranted.

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