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POSSIBLE SOURCE OF SECONDARY INVADING STAPHYLOCOCCI IN MICE EXPOSED TO ACUTE COLD
1Department of Biology, Bryn Mawr College, Bryn Mawr, Pennsylvania.
Abstract:
Miraglia, Gennaro J. (Bryn Mawr College, Bryn Mawr, Pa.) and L. Joe Berry. Possible source of secondary invading staphylococci in mice exposed to acute cold. J. Bacteriol. 85:345-348. 1963.-In an effort to determine the origin of the staphylococci known to invade the deep tissues (liver, spleen, kidneys, lungs, and heart) of mice exposed continuously to 5 C in individual compartments without bedding, the intestinal tract was freed of these organisms, as judged by absence of growth when fecal suspensions were inoculated into selective media. Substitution of 0.01 n hydrochloric acid for drinking water eliminated staphylococci within a few days, yet the incidence of tissue invasion was unaltered. The coagulase-negative strains normally present in feces and in tissues persisted in tissues even though the intestine was seeded with a coagulase-positive strain by feeding contaminated food. Cultures from the external nares continued unaltered. This suggests that the respiratory tract is a possible origin of the staphylococci found in tissues of the cold-stressed mice.
Insights
Researchers investigated the source of staphylococci in cold-stressed mice. Eliminating intestinal bacteria did not prevent tissue invasion, suggesting the respiratory tract as a potential origin for these secondary infections.
Area of Science:
- Microbiology
- Immunology
- Environmental Health
Background:
- Staphylococci are known to invade deep tissues in mice exposed to cold stress.
- The origin of these secondary invading staphylococci in cold-stressed mice remains unclear.
Purpose of the Study:
- To identify the primary source of staphylococci that invade deep tissues in mice subjected to acute cold exposure.
Main Methods:
- Mice were exposed to 5 C without bedding.
- The intestinal tract was cleared of staphylococci using selective media and hydrochloric acid in drinking water.
- Fecal suspensions and external nares cultures were analyzed.
- Mice were fed contaminated food to introduce coagulase-positive strains.
Main Results:
- Eliminating intestinal staphylococci did not alter the incidence of deep tissue invasion.
- Coagulase-negative strains persisted in tissues despite intestinal manipulation.
- Introduction of coagulase-positive strains into the intestine did not prevent invasion from other sources.
- External nares cultures remained unchanged.
Conclusions:
- The intestinal tract is unlikely to be the primary source of staphylococci invading deep tissues in cold-stressed mice.
- The respiratory tract, specifically the external nares, is a potential origin for these secondary infections.
