Cross-infection

Ayliffe G.A.J., Coates D. Hofifinan P.N. (1993) Chemical Disinfection in Hospitals. London PHLS. British Medical Association (1989) Code of Practice for Sterilization of Instruments and Control of Cross Infection. London BMA (Board of Science and Education). 

In hospitals today a wide variety of complex equipment is used in the course of patient treatment. Humidifiers, incubators, ventilators, resuscitators and other apparatus require proper maintenance and decontamination after use. Chemical disinfectants used for this purpose have in the past through misuse become contaminated with opportunist pathogens, such as Ps. aeruginosa, and ironically have contributed to, rather than reduced, the spread of cross-infection in hospital patients. Disinfectants should only be used for their intended purpose and directions for use must be followed at all times. 

Finally, intravenous drug administration and the sharing of needles and syringes is common among opiate addicts this creates a serious risk of cross-infection. Many studies have shown a high incidence of HIV and hepatitis B and C among heroin addicts. This risk is somewhat reduced in medically controlled narcotic prescription... 

Anderson, T.J. (1995) Ascaris infections in humans from North America molecular evidence for cross-infection. Parasitology 110, 215-219. 

Bretag T W and Merriman P R (1981), Epidemiology and cross-infection of Claviceps purpurea", Trans. Br. Mycol. Soc., 77, 211-213. 

To reduce nuisance from odours and dust around the building or reduce the chances of cross-infection to livestock in nearby buildings, air leaving the building is sometimes filtered. 

Lift crops during dry weather if possible, to prevent cross-infection of healthy tubers at harvest. Avoid wounding tubers. Never save tubers from infected plants for seed. Maintain storage temperatures at39°F (4°C) to inhibit new infections. 

In community-acquired cases the source of the infectious agent may be in the environment (food, water, animals, contagious persons) or the commensal flora of the patient in nosocomial cases the majority of infections are caused by commensals although cross-infections do occur under suboptimal hygienic conditions. Host factors usually determine the risk of nosocomial infection. 

Ehrenkranz, N.J., Taplin, D., and Butt, P., Antibiotic-resistant bacteria on the nose and skin colonization and cross-infection. Proceedings from Sixth Interscience Conference on Antimicrobial Agents and Chemotherapy. Philadelphia American Society for Microbiology. Antimicrob. Agents Chemother. 255-264,1966. 

Animals inoculated with sterile allantoic fluid should not be housed with Sendai infected animals to prevent cross infection. 

Sutde, C. A., and Chan, A. M. (1993). Marine cyanophages infecting oceanic and coastal strains of Synechocoaus Abundance, morphology, cross-infectivity and growth characteristics. Mar. Ecol Prog. Ser. 92, 99-109. 

HBV can be transmitted from one infectious inpatient to another (so-called cross-infection). 

Patients can be infected by contaminated blood and blood constituents as well as instruments or equipment. Here, too, cross-infections are of considerable relevance. 

The most prominent adverse reaction of the lincosamides is diarrhea, which varies from mildly loose bowel movements to life-threatening pseudomembranous colitis (see monograph on Beta-lactam antibiotics). Almost all antimicrobial drugs have been associated with severe diarrhea and colitis however, lincomycin and clindamycin have been particularly incriminated. The incidence of clindamycin-induced diarrhea in hospital is 23%. Diarrhea resolves promptly after withdrawal in most cases. It seems to be dose-related and may result from a direct action on the intestinal mucosa. Severe colitis due to C. difficile is not dose-related and occurs in 0.01-10% of recipients. Clustering of cases in time and place suggests the possibility of cross-infection. Even low doses of clindamycin, in some cases after topical administration, can cause marked alterations in several intestinal functions related to bowel flora (23). There was reduced susceptibility of C. difficile to clindamycin in 80% of French isolates in 1997 (24). Lincomycin was among the antibiotics that were most often associated with the development of antibiotic-associated diarrhea in a Turkish study of 154 patients other associated antibiotics were azithromycin and ampicillin (25). 

Although routine smallpox vaccination of infants was discontinued in the UK in 1971, some 20-28 cases of complications of vaccination continue to be reported yearly to the Committee on Safety of Medicines (64), including both cross-infection and fetal infection (64). 

Tests on a number of these small units revealed that the ozone concentration in the room was less than 0.01 p.p.m. by weight. There is ample evidence that various food odors, such as from fish, onions, acrolin from burnt fat, and tobacco as well as body odors can be oxidized by ozone. This is substantiated by many reports in the literature (4,13-15j 30y SI). Tests made in the laboratory with various unsaturated organic compounds such as indole and skatole (fecal odor), allyl sulfide (garlic odor), and methyl thiocyanate (unpleasant odor of almonds) showed them to be readily oxidized, as evidenced by lack of odor. Saturated compounds such as butyric and valeric acids were not oxidized under the same conditions. Special fixures with ultraviolet lamps producing a controlled amount of ozone are used in animal hospitals and kennels for prevention of cross infection and for the oxidation of animal and fecal odors. 

A number of important infectious diseases are spread via microbial contamination of the air. This cross-infection can occur in a variety of situations — hospitals, cinemas, aeroplanes —while main-... 

Organic acids have also been proposed to be used in rearing water systems for broilers to reduce cross-infection of Campylobacter spp. on a farm. However, further research is necessary to specify the exact effect of acidified water on the transmission of Campylobacter among chickens (Chaveerach et al., 2002). 

B. Isolation Procedures (Barrier Nursing). In the context of biological agent casualties, adherence to principles of patient isolation is essential to preventing cross-infection with transmissible agents. 

Convenience is normally associated with product use or administration. It may be a feature related to the pack, e.g. a metered dose aerosol, or related to the product-pack, e.g. a unit dose eye drop which both eliminates the need for a preservative and reduces risks associated with cross-infection, by administering only a single dose. 

Microorganisms are frequently transferred by cross-infection due to hand contact between hospital staff and patients. Cross-infection has been estimated to account for 10-20% of hospital-acquired infections [5]. Hand-body contact, or contact spread, is a mode of nosocomial transmission that is particularly hard to control because the pathogens are environmentally robust and generally more resistant to antimicrobials. 

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