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THE PATHOLOGIC EFFECTS OF STREPTOCOCCI FROM CASES OF POLIOMYELITIS AND OTHER SOURCES

C G Bull1

  • 1Laboratories of The Rockefeller Institute for Medical Research.

The Journal of Experimental Medicine
|October 30, 2009
PubMed

Insights

This study found that streptococci bacteria, isolated from poliomyelitis patients, did not cause poliomyelitis in laboratory animals. These bacteria are considered secondary invaders, not the cause of poliomyelitis.

Area of Science:

  • Microbiology
  • Virology
  • Neurology

Background:

  • Poliomyelitis is a serious infectious disease affecting the nervous system.
  • The role of bacterial co-infections in poliomyelitis pathogenesis has been investigated.
  • Streptococci have been cultured from poliomyelitis patients.

Purpose of the Study:

  • To determine if streptococci isolated from poliomyelitis cases can induce poliomyelitis in laboratory animals.
  • To investigate the pathogenic potential of these streptococci in various animal models.
  • To assess any potential etiological or pathological relationship between streptococci and poliomyelitis.

Main Methods:

  • Inoculation of laboratory animals (guinea pigs, dogs, cats, rabbits, monkeys) with streptococci from poliomyelitis patients.
  • Observation for clinical and pathological signs resembling poliomyelitis.
  • Isolation and characterization of lesions in infected animals.
  • Inoculation of monkeys with streptococci from poliomyelitic nervous tissue.
  • Testing of cross-protection and viral neutralization in monkeys post-streptococcal infection.

Main Results:

  • No animal developed poliomyelitis after inoculation with streptococci.
  • A significant percentage of rabbits and some other animals developed various lesions (meningitis, encephalitis, abscesses, arthritis, etc.) due to streptococci.
  • No difference in lesion type or frequency was observed between streptococci from poliomyelitis patients and other sources.
  • Streptococci from infected monkey nervous tissue did not cause poliomyelitis in other monkeys.
  • Monkeys recovered from streptococcal infection were not protected against the poliomyelitis virus.

Conclusions:

  • Streptococci isolated from poliomyelitis patients are not the etiological agent of poliomyelitis.
  • These streptococci act as secondary invaders, causing various lesions but not poliomyelitis itself.
  • There is no detected etiological or pathological link between streptococci and epidemic poliomyelitis or experimental poliomyelitis in monkeys.

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