Pathogen inactivation

Turner, C., Williams, A., White, R., and Tillett, R. (2005). Inferring pathogen inactivation from the surface temperatures of compost heaps. Bioresource Technol. 95,521-529. 

Cryoprecipitate should be used to treat bleeding in the setting of factor VIII deficiency and von Willebrand disease only in an emergency in which pathogen-inactivated products are not available. 

Cryoprecipitate may also be used for patients with factor VIII deficiency and von Willebrand disease if desmopressin is not indicated and a pathogen-inactivated, recombinant, or plasma-derived product is not available. The concentration of factor VIII and von Willebrand factor in cryoprecipitate is not as great as that found in the concentrated plasma fractions. Moreover, cryoprecipitate is not treated in any manner to decrease the risk of viral exposure. For infusion, the frozen cryoprecipitate unit is thawed and dissolved in a small volume of sterile citrate-saline solution and pooled with other units. Rh-negative women with potential for childbearing should receive only Rh-negative cryoprecipitate because of possible contamination of the product with Rh-positive blood cells. 

The resulting UV intensity can then be used to determine the UV dose. A pathogen inactivation experiment result is related to the UV dose. The typical experiment will consist of most probable number (MPN) procedure for bacteria, a plaque count procedure... 

Infection risk A review and analysis of pathogen-inactivated blood products cited the concern of increased bleeding however, most of the world has transfused these products for a number of years without bleeding complications [28 ]. Authors argue that years of safe use internationally, combined with the reduced-risk of bacterial contamination, are reasons to adopt the technology in the United States. 

Kleinman S, Reed W, Stassinopoulos A. A patient-oriented risk-benefit analysis of pathogen-inactivated blood components application to... 

At 70—140°C, peroxide is vaporised. Peroxide vapor has been reported to rapidly inactivate pathogenic bacteria, yeast, and bacterial spores in very low concentrations (133). Experiments using peroxide vapor for space decontamination of rooms and biologic safety cabinets hold promise (134). The use of peroxide vapor and a plasma generated by radio frequency energy releasing free radicals, ions, excited atoms, and excited molecules in a sterilising chamber has been patented (135). 

The current concept of disinfection is that the treatment must destroy or inactivate viruses as well as bacillary pathogens. Under this concept, the use of coliform counting as an indicator of the effectiveness of disinfection is open to severe criticism given that coliform organisms are easier to destroy than viruses by several orders of magnitude. 

AOPs are valuable tertiary treatments allowing not only inactivation of a wide spectrum of pathogens but also the removal of a great number of the so-called emerging pollutants (pharmaceutical, personal care products). These are not totally removed during conventional treatment, but remain in the wastewater effluents [33]. Among different alternatives electrochemical oxidation with bom doped diamond electrodes (BDD) has been reported to be effective on eliminating... 

Only a small fraction of faecal contaminants contributed to the enviromnent through human and animal faeces reach new hosts to infect them. Many of the defecated microorganisms never reach the soil and/or water bodies, since faecal wastes are submitted to purification (water) and hygienization (solids) processes, which remove a fraction of the pathogens and indicators. An important fraction of those that reach either the soil or water are removed (adsorption to soil particles and suspended solids, followed by sedimentation) and/or inactivated by natural stressors (physical, chemical and biological) in soil and water bodies. 

Heat is the most reliable method of virus disinfection. Most human pathogenic viruses are inactivated following exposure at 60°C for 30 minutes. The virus of serum hepatitis can, however, survive this temperature for up to 4 hours. Viruses are stable at low temperatures and are routinely stored at -40 to -70°C. Some viruses are rapidly inactivated by drying, others survive well in a desiccated state. Ultraviolet light inactivates viruses by damaging their nucleic acid and has been used to prepare viral vaccines. These facts must be taken into account in the storage and preparation of viral vaccines (Chapter 15). 

Moulds and yeasts show varying responses to biocides. These organisms are often important in the pharmaceutical context because they may cause spoilage of formulated products. Various types of protozoa are potentially pathogenic and inactivation by biocides may be problematic. Viral response to biocides depends upon the type and structure of the virus particle and on the nature of the biocide. 

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