Fate of Staphylococcus aureus in Bruised Tissue12

Abstract

HAMDY, M. K. (University of Georgia, Athens), AND N. D. BARTON. Fate of Staphylococcus aureus in bruised tissue. Appl. Microbiol. 13:15-21. 1965.-This investigation was initiated to determine the fate and behavior of a virulent marker strain of Staphylococcus aureus (MS) injected intramuscularly into both control and traumatized tissues. Control tissues appeared to possess a clearing mechanism highly active against this organism, whereas bruised tissues stimulated and supported its growth. This stimulation may be due to the presence of extrastromal hemoglobin in the bruised areas. By use of the disc-sensitivity procedure, extrastromal hemoglobin was found to enhance the growth of S. aureus (MS) and this stimulation was linearly dependent on concentration in the range of 0.002 to 0.008 ,mole per disc. Physical and physiological factors affecting the fate of staphylococci in poultry tissues were studied. The results showed that the number of viable cells of S. aureus (MS) in the initial inoculum exerted little effect on the survival activity patterns of this organism in the traumatized tissues. Control tissues, however, only became infected when a suspension containing 1.34 X 109 cells of the marker strain was injected. Regardless of the concentration of cells of this test culture inoculated into bruised areas, the staphylococci did not increase in number above a log of 8.5 organisms per gram of tissue. The extent of both tissue damage and accumulation of blood and fluid seemed to play an important role in the fate of staphylococci in experimentally induced infection. A correlation was noted between the severity of the bruise and the rate of growth and multiplication of virulent staphylococci in the tissue. The rate of growth showed a 100-fold increase in 1 day in the severe bruise, in 2 days in the medium bruise, and in 3 days in the superficial bruise. Time-course studies revealed that virulent S. aureus (MS) was able to persist in bruised tissue for long periods of time (18 days) even in the absence of noticeable infection. Therefore, it is believed that bruised tissue is a source of contamination to other birds and a health hazard to man.

PERSISTENCE OF STAPHYLOCOCCUS. Bruised Tissue Microenvironment Affecting Persistence of Staphylococcus aureus

“…Cells were then harvested by centrifugation, washed twice with sterile saline then resuspended in saline to the desired concentration. The latter was checked by plating appropriate dilutions on (Difco) mannitol-salt-agar (MSA) (Hamdy and Barton, 1965).…”

“…POULTRY BRUISES harbor large numbers and various kinds of bacteria of which Staphylococcus aureus is predominant (McCarthy et al, 1963). These staphylococci are able to combat host defense mechanisms and persist in the bruised tissue for more than 18 days (Hamdy and Barton, 1965). Poultry bruises were implicated as a source of the staphylococcal infections that commonly occur on the hands, arms, chest and abdomen of poultry processing-line workers (Roskey and Hamdy, 1972).…”

Bruised Poultry Tissue as a Possible Source of Staphylococcal Infection

“…Microbiological examination of poultry bruises by McCarthy et al (10) revealed that these tissues harbor large numbers of various types of bacteria, particularly Staphylococcus aureus. It was also reported that bruised tissue supported and stimulated the growth of Escherichia coli and S. aureus in vivo (5,6). The latter organism was able to persist in injured tissues for 18 days, even in the absence of noticeable infection (5).…”

“…It was also reported that bruised tissue supported and stimulated the growth of Escherichia coli and S. aureus in vivo (5,6). The latter organism was able to persist in injured tissues for 18 days, even in the absence of noticeable infection (5). Although higher incidence of staphylococcal infections occurred in the wounds of poultry workers in the Clarke County areas as compared to the population at large (5), no epidemiological studies had been conducted to ascertain a definite source.…”

“…The latter organism was able to persist in injured tissues for 18 days, even in the absence of noticeable infection (5). Although higher incidence of staphylococcal infections occurred in the wounds of poultry workers in the Clarke County areas as compared to the population at large (5), no epidemiological studies had been conducted to ascertain a definite source. These infections appeared among the employees of the poultry processing plants who came in contact with live chickens and carcasses during the initial stages of dressing.…”