Universal screening of donated blood for transfusion-transmissible infections (TTIs) is critically important to provide safe blood transfusion and give individuals confidence in their health care system. Safe blood transfusion is an ethical imperative, as health care systems should do no harm. Because infection after receipt of HIV-infected blood occurs in 95%-100% of recipients and, without therapy, will result in death,1 HIV is the most important of the TTIs. Universal access to safe blood cannot be achieved without systems and mechanisms for ensuring quality and continuity in screening.2
A lack of access to safe blood can be caused by many factors, including weak health systems, rural settings, potentially risky donors, unnecessary transfusion and insufficient HIV screening for HIV, hepatitis viruses and other transmissible diseases.3 In some countries, interruptions to supplies of test kits and reagents, or emergency situations, can result in the use of blood for transfusion without prior screening for TTIs.3
In 2000, United Nations (UN) Member States agreed on a series of Millennium Development Goals (MDGs). A year later, Member States attending the Special Session of the UN General Assembly on AIDS (UNGASS) signed a Declaration of Commitment on HIV/AIDS. That Declaration supported MDG 6 (halting and beginning to reverse the HIV epidemic by 2015) and also called for regular assessment of national, regional and global progress against HIV, using a series of core indicators developed by the United Nations Programme on AIDS (UNAIDS) and diverse partners.
Using those “UNGASS indicators” and other data sources, the 2006 Report on the global AIDS epidemic assessed progress in achieving blood safety since 2001.4 Only 40 countries of 122 reporting countries contributed data on the blood safety indicator in 2006. That low number seems to have been partly due to the lack of data and data collection systems or the unspecific wording of the indicator. In addition, many countries reported numerators that were larger than the denominators, leading to indicator values higher than 100%. Reported data therefore did not allow for an accurate assessment of the global status of blood safety. Under those circumstances, the Global Monitoring and Evaluation Reference Group and Indicator Working Group on blood safety revised the UNGASS blood safety indicator in 2006-2007. The new indicator includes a quality assurance component, which requires use of a standard operating procedure and external quality assessment.5
Other data can be used to assess global blood safety. The Global Database on Blood Safety (GDBS) was established by the World Health Organization (WHO) in 1997 to address global concerns about the safety and availability of blood for transfusion.2 This survey includes various aspects of blood safety such as administration, management, donation, screening, transportation and use of blood. We analyzed data obtained by UNGASS reporting and the WHO GDBS to evaluate the safety of blood transfusion globally.
We examined data from reports on the global AIDS epidemic (2006 and 2008),4 using UNGASS country profiles. We also analyzed data from the GDBS (2004-2005 and 2006)2 for comparison with UNGASS data and validation of the accuracy and consistency of data.
UNGASS Indicators on Blood Safety
We used the latest UNGASS indicator on blood safety, as defined by the “Guidelines on Construction of Core Indicators” in 2007.5 The indicator differs from previous indicators in that it monitors blood that is donated, as opposed to transfused, and includes the assessment of quality assurance of screening (Table 1). Two key components of the new indicator are (1) the use of documented and standardized procedures (standard operating procedures) for the screening of every unit of donated blood, and (2) participation of the laboratories in an external quality assessment scheme for HIV screening in which external assessment of the laboratory's performance is conducted using samples of known, but undisclosed, content to assess quality control systems and assist in improving standards of performance.
Data were submitted to UNAIDS by national governments via national AIDS committees or equivalent institutions, using data collected with a data collection instrument developed by the WHO GDBS, and with other relevant data collection mechanisms.
The WHO's Blood Transfusion Safety collected information on blood safety from Ministries of Health or equivalent organizations through the GDBS.2 In 2007-2008, WHO collected blood safety data, which included the number and percentage of donations screened for TTIs and the percentage of donated blood units screened for TTIs in a quality assured manner.6 In addition, the data can be disaggregated by laboratory, making this database compatible with the new UNGASS indicator. Data collection occurred from January to December 2006. The authors also collected datasets from previous GDBS reports to examine the performance of 2008 data.2
Data Processing and Analysis
For UNGASS reporting, all data submitted by countries were stored in the Global Response Database, developed by UNAIDS to manage data submitted by countries and were exported for further analysis. To validate the data, UNAIDS performed initial data review processes by cross-checking the consistency and completeness of denominators and numerators, followed by a reconciliation process conducted by a WHO and UNAIDS joint committee. The committee reviewed all information by comparing these data with both the previous UNGASS data and the GDBS data and identified discrepancies or areas of uncertainty. This was followed by queries to countries and a review of responses submitted by countries. Subsequently, the data were analyzed to produce statistical values using STATA 9.
Countries reporting UNGASS indicators in 2008 numbered 147 (of 192 UN Member States) and 125 of them (85%) reported blood safety data (Fig. 1). This is one of the highest reporting ratios of all UNGASS indicators. There was a low reporting proportion for high-income countries (44%), compared with other groups such as upper middle-income (76%), lower middle-income (65%) and low-income (77%) countries. The mean indicator values by income status were 97%, 99%, 85% and 88%, respectively.
The data show that blood safety was lowest in Eastern Europe and Central Asia, where the mean value of the UNGASS indicator was 76% and highest in the high-income countries-albeit with important regional variation (Table 2). In Eastern Europe/Central Asia and sub-Saharan Africa, for example, some countries reported that 0% of blood was screened in a quality assured manner, whereas others reported 100%.
Most countries (91 of 125 countries, 73%) reported that 100% of collected blood units were screened for HIV in a quality assured manner. However, 34 countries (27%) reported values of less than 100% and 4 countries reported 0%. Thirty countries reported more than 0%, but less than 100% of collected blood units were screened in a quality assured manner and these were almost evenly distributed in this range (Fig. 2).
The GDBS report (2004-2005) contained responses from national health authorities in more than 170 countries. Globally, 80.7 million donations of whole blood were collected annually in 167 countries during 2004-2005. Of those, 77.3 million donations were tested for HIV, and at least 0.6 million of the remaining 3.4 million donations were not tested. Developing countries are home to more than 80% of the world's population, but they currently represent only 45% of the global blood supply. The quality of testing is uncertain: 75 of the 145 countries (52%) reporting 100% HIV testing either did not use or did not verify the use of standard operating procedures in all centres.7
HIV continues to be transmitted by blood transfusion due to the lack of screening and lack of universal quality assured screening.7 To assess progress in screening blood for HIV, the first blood safety indicator of UNGASS was reported in 2006. However, the results prompted questions about the accuracy and feasibility of this indicator. The blood safety indicator was revised in 2007 in collaboration with WHO to arrive at a more precise indicator.5 The new definition, along with intensive UNGASS training and coordinated efforts with WHO, improved country response rates and the number of reporting countries increased from 40 to 125.4
In 2008, reporting rates for the Caribbean region (100%) and low-income and middle-income countries generally were relatively high (65%-77%), compared with other regions (34%-85%) and high-income countries (44%). Indicator values of blood safety also showed wide variation, ranging from 0% to 100% of blood units screened in a quality assured manner, depending on the country. Among 4 countries reporting 0%, national adult HIV prevalence varied from less than 0.1% to 1.6% in 2007. The latter instance is a serious concern because an estimated 440,000 people were living with HIV in that country in 2007.4 In another country with low indicator value (36%) and high national adult HIV prevalence (12.5%), an estimated 1.5 million people were living with HIV in 2007.4
Ninety-one countries reported having taken steps to ensure the screening of all donated blood for HIV and to ensure that necessary quality assurance processes are in place. However, 34 countries reported that they do not screen all donated blood for HIV in accordance with quality standards, whereas a further 67 countries did not report information on this indicator.4 There were varying degrees of nonreporting rates: 56% for high-income countries (most of them in Europe), 24% for upper middle-income, 35% for lower middle-income and 23% for low-income countries.4 Of these 67 countries, 7 are experiencing generalized HIV epidemics and are located in Africa.4 Special efforts are needed to acquire data from these countries and (where universal quality assured screening is lacking) to help determine underlying causes of the situation. Although the revised UNGASS indicator helped to increase reporting rates from 21% (40 countries) to 65% (125 countries), there are still insufficient data to conduct in-depth analysis and to determine trends.
In addition to having safe blood, blood must be available to those in need. According to GDBS data, there is a particular gap between blood supply and potential needs in sub-Saharan Africa, based on the number of units of donated blood compared with other regions. Blood donations in sub-Saharan Africa totaled an estimated 3.2 million units (6.3% of the global total), but that region contains about 14% of the world's population.7 The same figures for Western and Central Europe are 27% (blood donation) and 5% (population size).7 The GDBS data in 2001/2002 showed that the average donations per 1000 population in Africa, Southeast Asia, Western Pacific and Europe region were 5.7, 9.2, 17.1 and 39.9 units, respectively.
There are several possible explanations for this disparity between the developing and industrialized world. Surgery may be more common in industrialized countries than in low-income and middle-income countries, and it may be more complicated and require more blood. Nevertheless, the GDBS suggests that further progress must be made in collecting blood in low-income and middle-income countries. When collected, blood must be screened universally in a quality assured manner. In addition to providing quality assured blood testing, other efforts are needed to improve blood safety. Avoiding remuneration of donors, or using family donors, reduces the likelihood of collecting infected units.8 Training health care providers in the proper use of blood can lower the risk of HIV infection, as up to 50% of transfusions continue to be unnecessary.9,10 Overall efforts at improving blood safety can make the contribution of unsafe blood transfusion to overall HIV incidence negligible in countries where it previously was a significant risk.11
We reviewed literature and analyzed progress in global blood safety compared with other HIV interventions and cost-effectiveness to maximize limited resources in developing countries.
Ensuring the safety of blood transfusion is cost effective.12 For instance, the cost per HIV infection prevented is US $18 for blood safety, US $275 for condom distribution for sex workers, US $393-$482 for voluntary HIV counseling and testing and US $3834 for prevention of mother-to-child transmission.12 This is explained, in part, by the high efficiency of transmission via blood transfusion (95%-100%), compared with mother-to-child transmission (11%-32%) or infection through sexual contact (0.1%-10%).1
Although the cost of HIV treatment varies widely among countries and has been dramatically reduced,13 blood safety remains cost effective, and the WHO recommends cost effective strategies for blood safety.14 The Report of the Secretary General on the Declaration of Commitment on HIV/AIDS noted that 2.5 million people were newly infected with HIV in 2007.15 This highlights the importance of continued efforts to scale up HIV prevention. It is estimated that almost 500,000 potential HIV infections via blood transfusion are averted each year in sub-Saharan Africa through the adoption of simple blood safety measures in voluntary blood donation, blood donor selection and quality assured testing of donated blood.8 Quality assured blood screening remains a critically important and cost-effective HIV prevention strategy.
Several gaps in blood safety have been identified and discussed through UNGASS processes, including lack of screening, inadequate screening quality, blood donation availability and access to safe blood, technical support and capacity building, proper use of blood and cost effectiveness. Further efforts are needed to improve quality assured blood screening for HIV with standard procedures, quality scheme and proper test kits. Data collection, data validation and reporting around blood safety must also be strengthened. Although more countries reported the revised UNGASS indicator in 2008, many did not and for unknown reasons. Those countries not reporting data should be strongly encouraged to report and cite the reasons for reporting if they do not. This is particularly important when the prevalence of HIV is high: outside agencies can not assist unless a problem is identified.
More than 20 years after sensitive screening testing systems became available, failure to screen all donated blood for HIV in accordance with minimum quality standards is a cause for grave concern. All HIV transmission through contaminated blood must be eliminated if we are to achieve MDG 6 to halt and begin to reverse the global HIV epidemic by 2015.
The authors would like to thank Jan Fordham (WHO), Yves Souteyrand (WHO), Ju Yang (UNAIDS), Ali Safarnejad (UNAIDS), Magomed Nashkhoev (UNAIDS), Matthew Warner-Smith (UNAIDS) and Peter Ghys (UNAIDS) for their valuable contribution and comments to this article. We thank the countries which submitted blood safety data and WHO or UNAIDS regional/country offices for their kind cooperation.
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15. UN. Declaration of Commitment on HIV/AIDS and Political Declaration on HIV/AIDS: midway to the Millennium Development Goals: Report of the Secretary-General