الفهرس 
AcknowledgmentOnly 14 pages are availabe for public view
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Abstract
Summary
Despite the fact that human parvovirus B19 is a serious infectious agent that can be transmitted through blood transfusion, contaminate blood and blood products, and causes many serious complications in some recipients, till now the donor screening for B19 is not obligatory in our country.
Human Parvovirus B19 is a serious infectious agent responsible for causing several diseases and clinical complications including erythema infectiosum or fifth disease (a common childhood disease), aplastic crisis, fetal hydrops and abortion.
After being infected with B19, the human body produces specific immunoglobulin M (IgM) and immunoglobulin G (IgG) antibodies.
Human Parvovirus B19 is a member of the family parvoviridae , genus Erythroparvovirus and until 2005, B19 was the first and the only known human virus in this family, it’s one of the smallest viruses with DNA genome as it’s diameter is between 23-26 nm, B19 is a non-enveloped virus, it has an icosahedral shape and it has a linear single stranded DNA genome.
Acquiring infection with B19 through the process of blood transfusion is serious and really problematic especially in certain group of blood recipients, this group is called the high risk group of patients and this group includes pregnant women, patients suffering from haematological diseases such as patients with special types of anemia and patients who are multi-transfused constantly such as immunodeficient patients.
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Summary and Conclusion
In this study the prevalence of antibodies against B19 as well as the prevalence of the B19 viral genome among the donor population was determined in order to get the full image about how B19 is actually present in the community and constitutes a dangerous and also a serious transfusion risk, the results of this study indicated the risk of Human Parvovirus B19 being endemic among the population in our country and the fact that B19 is indeed a high risk infection for blood recipients.
The study was conducted at the blood Bank, Suez Canal University Hospital, Ismailia, Egypt.
A total of 500 Blood Donors within the age range of 18-55 years attending the blood bank of the hospital were included in the study.
Blood samples were collected, and the serum was separated and stored at (‒20⁰C) until use.
The donors’ serum samples were screened for antibodies against human parvovirus B19 by ELISA technique, and were screened for human parvovirus B19 genome by PCR.
Parvovirus B19 IgM and IgG antibodies were assayed using The recombinant NovaTec Parvovirus B19 IgM-ELISA and The recombinant NovaTec Parvovirus B19 IgG-ELISA respectively, following the manufacturer’s instructions.
Human Parvovirus B19 genome was detected by PCR analysis, the donors’ serum samples were screened for B19 DNA using Artus Parvo B19 LC PCR Kit.
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Summary and Conclusion
The results of this study showed that:
1-The prevalence of IgM antibodies against human parvovirus B19 in this study was 6.20%.
2-The prevalence of IgG antibodies against human parvovirus B19 in this study was 80.20%.
3-In the present study the seroprevalence of IgG antibodies against human parvovirus B19 is very high compared to previous studies
4- In this study, the prevalence of anti B19 IgG antibodies was found to be at highest levels in donors belonging to (25<35) age group.
5- The prevalence of human parvovirus B19 genome in this study was 3.00%.
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Summary and Conclusion
Conclusion
Human parvovirus B19 genome can persist in the healthy, immunocompetent individuals for long periods and detection of B19 DNA by PCR analysis, is not always indicative of recent infection with B19.
There is a high prevalence of Human parvovirus B19 among the population of blood donors in Ismailia, Egypt, and this is clearly an evident that there is an active B19 transmission in the community, therefore screening for B19 before donating blood is highly recommended and can be considered as an essential procedure to be undertaken prior the process of blood donation in the future to ensure that blood supply is totally safe for recipients.
In case of chronic B19 infection the viral DNA can persist in the host without the presence of B19 IgM or IgG antibodies.
The majority of the adult population has been exposed to the virus previously during their lives, (the adult population is represented by the 500 donors subjected to screening in this study), and this is concluded from the high prevalence of anti B19 IgG antibodies in this study.
The seroprevalence of human parvovirus B19 among blood donors in this study is high; hence there is a serious risk during the blood transfusion process, if the blood contaminated with B19 became transfused to high-risk group of patients.
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Summary and Conclusion
The B19 infectious level (the B19 level that triggers the infection in the recipient) in blood bags (blood donations) and blood products hasn’t been exactly determined yet, and this level probably depends on the level of anti B19 IgG antibodies co-present in the blood bag or the blood product in addition to the immune status of the recipient, and there is a certain level of anti B19 IgG antibodies (though this level is not determined yet), that certain level of anti B19 IgG antibodies (if present in the donation) will make the blood or blood product not infectious and will not cause an infection with B19.
It is a fact that infection with B19 can be transmitted through contaminated blood products, but till present day there are no strict regulatory procedures to control and exclude any chances of B19 contamination before releasing blood or blood products to the recipients.