Blood products hepatitis

More recently, a recombinant non-infec-tious subunit viral vaccine derived from the hepatitis B surface antigen (Recombi-vax HB) has been developed. The antigen is produced in fermentation cultures of Saccharomyces cerevisiae, and is therefore free from human blood products. Hepatitis B is an inflammation of the liver caused by the hepatitis B virus, and can be very serious or even fatal. The virus is usually spread by contact with infected blood, though an infection can be prevented by vaccination. The vaccine is highly immunogenic, well-tolerated, and possesses an excellent protective efficacy that leads to immunity for 10 years. 

In 1983 the move to develop red cell substitutes intensified when it was recognized that the acquired immune deficiency syndrome (AIDS) could be transmitted by the blood-bome human immunodeficiency vims (HIV). Concern for the nation s blood supply followed. Since that time other retrovimses have been identified, efforts to screen blood not only for these agents but also for vimses that cause hepatitis have intensified, the indications for transfusion have been reevaluated, and the use of blood products has become much more efficient. More carehil screening of donors, testing of all donated units, and a general awareness in the donor population have all contributed to a decreased risk from transfusion-contracted AIDS. 

Different conformity assessment options are available, depending on the type of device and the level of associated risk. For lotv-risk devices, the manufacturer can make a declaration of conformity based solely on self-assessment, without the need for the involvement of a Notified Body. For all other devices Notified Bodies are required to perform one or more of the tasks outlined in Table 10.2. HIV and hepatitis tests and blood grouping tests represent the highest risk devices, as they are critical to ensuring the safety of blood and blood products. For example, a defective HIV test device could result in widespread infection in an unsuspecting population, whereas the detrimental effects ofan AIMD or a Class III device failure will just be confined to the individuals treated by the device. At this end of the risk spectrum. Notified Bodies are required to verify the applied quality system, the specific device design, and the... 

Hepatitis C virus (HCV) Spherical particles 40 nm in diameter consisting of an inner core surrounded by an adherent lipid envelope The virus is spread through blood transfusions and blood products. Induces a hepatitis which is usually milder than that caused by HBV... 

Individuals may minimize their risk of acquiring both hepatitis B and C infection by avoiding contaminated blood products and not indulging in high-risk behavior such as intravenous drug use. 

Intravenous drug users using unsterilized needles Workers involved with non-human primates Food service handlers Patients with clotting factor disorders Individuals residing in health care institutions Hepatitis B and Hepatitis D Men having sex with other men Individuals with multiple heterosexual partners Intravenous drug users using unsterilized needles Recipients of blood products... 

The risk factors for hepatitis C and hepatitis B are quite similar thus, the risk of acquiring the HCV is minimized by avoiding contaminated blood products and high-risk behaviors... 

It overcomes problems of product safety. Direct extraction of product from some native biological sources has, in the past, led to the unwitting transmission of disease. Examples include the transmission of blood-borne pathogens such as hepatitis B and C and human immunodeficiency virus (HIV) via infected blood products and the transmission of Creutzfeldt-Jakob disease to persons receiving human growth hormone (GH) preparations derived from human pituitaries. 

Biopharmaceutical products are also subjected to screening for the presence of viral particles prior to final product release. Although viruses could be introduced, for example, via infected personnel during downstream processing, proper implementation of GMP minimizes such risk. Any viral particles found in the finished product are most likely derived from raw material sources. Examples could include HIV or hepatitis viruses present in blood used in the manufacture of blood products. Such raw materials must be screened before processing for the presence of likely viral contaminants. 

Associated with the administration of blood or blood products is the risk of accidental transmission of infectious agents such as hepatitis viruses or HIV. The prevention of accidental pathogen transmission relies upon ... 

The problem of quality control in donor blood and blood products is of great importance for a health service in practice. Among infectious agents that contaminate blood, mention should be made of human immunodeficiency vims, hepatitis B and C vimses, and human cytomegalovirus (Ender, 2004 Mohr, 2000). In the past decade, the role of... 

Better methods for preparing clotting factors from blood and the development of recombinant clotting factors provided the solutions. Methods of detecting, inactivating, and removing viruses were improved, and none of the hemophilia replacement products— conventional or recombinant—has transmitted either HIV or hepatitis since 1987. As an alternative, recombinant clotting factors 8 and 9, produced in animal cells, were approved in 1992 and 1997, without the risk associated with human blood products. 

Table 9.2. Some of the infectious agents that have been transmitted via administration of infected blood or blood products. Transmission of viruses, particularly hepatitis A and B virus and HIV, are most common...

For many years, blood transfusion has been a therapy for children and adults with sickle cell disease. Prior to the 1980s, due to the lack of availability of blood products and the standard of care at that time, transfusion was used infrequently and generally only for catastrophic complications of this disease. During the 1980s, the risk of infection through transfusion was so high that transfusion continued to be used infrequently. When reliable testing for infectious diseases (e.g., HTV and hepatitis) in blood products became available, the use of red cell transfusion became standard of care for complications of sickle cell disease. 

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