Addressing blood and body fluid spills: conserving time and resources during surface disinfecting.

As new issues and areas of concern arise in the health care industry, such as the potential transmission of HIV and HBV, adaptive measures will continue to be developed to assist health care professionals in their mission to provide expert medical care for patients and safe environments in which to practice. Health care institutions must commit to exploration of the advances in infection control that employ improved measures to manage the cleaning and disinfecting of spill incidents involving blood and/or body fluids and the disinfecting of contaminated surfaces. Together, product manufacturers and health care workers will discover new ways to save time, money, and resources. The goal for health care administrators should be to focus on products that stress simplicity, efficiency, cost containment, and, most important, the safety of staff and patients.

Plasmid deoxyribonucleic acid in clinical isolates of Neisseria gonorrhoeae.

Two different sizes of circular covalently closed deoxyribonucleic acid plasmids have been identified in four independent clinical isolates of Neisseria gonorrhoeae. All four strains contained a small plasmid with a molecular weight of 2.8 X 10-6 and two of the four stains also contained a large plasmid with a molecular weight of 24.5 X 10-6. The avirulent derivative of each of these four strains had the same plasmid complement as its virulent parent. There was no correlation between the presence of these plasmids and antibiotic resistance, piliation, and colony type associated with virulence, or ability to grow without seven specific amino acid supplements.

Co-transduction of plasmids mediating resistance to tetracycline and chloramphenicol in Staphylococcus aureus.

Independent plasmids mediating resistance either to tetracycline (Tc) or chloramphenicol (Cm) were transduced successively into Staphylococcus aureus strain 8325. From this doubly resistant donor strain, Tc was co-transduced with a frequency of 40 to 50% when Cm was selected. Co-transduction of Cm was 5 to 10% with Tc selection. Plasmid elimination was infrequent and restricted to the Cm plasmid. A variant, doubly resistant strain gave 100% co-transduction of Tc and Cm and a high rate of joint elimination of both plasmid markers. Co-transduction of the plasmids from recombination-deficient donor strains was much reduced if the plasmids had been introduced separately into the donor strain, but occurred at the normal high rate if they had been introduced jointly. The plasmids were co-transformed at relatively low rates with closed circular deoxyribonucleic acid (DNA) from doubly resistant donors, but not with DNA from a mixed lysate of singly resistant strains. Our evidence favored a hypothesis of recombination-dependent, reversible linkage between the two plasmids as the basis for their co-transduction. Examination of plasmid DNA from the doubly resistant strains by ultracentrifugal and electron microscopic methods did not disclose any physical differences between singly and doubly resistant strains that might account for the observed co-transduction.

Isolation and characterization of a kanamycin resistance plasmid from Staphylococcus aureus.

A circular covalently closed duplex deoxyribonucleic acid plasmid carrying genes for resistance to kanamycin/neomycin has been identified in Staphylococcus aureus E419. The plasmid has a molecular size of 9.2 x 10(6) daltons and can be transduced into or can transform competent susceptible strains of S. aureus to kanamycin/neomycin resistance.

Absence of circular plasmid deoxyribonucleic acid attributable to a genetic determinant for methicillin resistance in Staphylococcus aureus.

Plasmid deoxyribonucleic acid was not detected by centrifugal analysis of lysates of penicillinase-negative strains of Staphylococcus aureus harboring a determinant of methicillin resistance derived from strain Villaluz. When these strains contained a penicillinase plasmid, the plasmid deoxyribonucleic acid of methicillin-resistant and methicillin-susceptible strains was indistinguishable by the methods employed. The results indicate that the genetic determinant for methicillin resistance in the strains examined was not associated with a circular plasmid comparable to those that have been shown to determine resistance to benzylpenicillin, tetracycline, and chloramphenicol in S. aureus.