Percent Of Donations Research Articles

The global blood supply: a literature review

BackgroundA safe and sufficient blood supply is requisite for a functional surgical system. Although the disparity in blood donation rates between low-income and middle-income countries (LMICs) and high-income countries is well documented, less is known about the reasons for this inequity, which compromises efforts to remedy it. We aimed to review the state of the blood supply and elucidate unique country-specific challenges in each of the world's 196 countries. MethodsWe searched PubMed, MEDLINE, Google Scholar, and WHO reports using the search terms “blood donor”, “blood donation”,”blood safety”, “blood bank”, “transfusion safety”, and “blood services”. After an initial review of existing literature, we did a comprehensive country-by-country search of the aforementioned electronic databases, WHO regional reports, Ministry of Health websites, and National Blood Transfusion Services data for specific indicators and data points used to compare blood supply and safety across countries. These included donation rate per 1000 population, percent of donations from voluntary non-remunerated donors, number of blood banks or centres, and national blood policies. Both quantitative and descriptive data are included in a summary table in the appendix of the Lancet Commission on Global Surgery. FindingsOur review yielded 117 publications with data for 188 countries: 101 peer-reviewed manuscripts with 13 reporting data for high-income countries and 88 for LMICs, 16 WHO publications, and a subsequent search of select websites to collect additional country-specific indicator data. Generally, blood donation is limited because of poor health infrastructure (28 LMIC and four high-income country manuscripts), low public awareness of donation practices and safety (22 LMIC manuscripts), and stigmas surrounding voluntary blood donations, especially in LMICs. Most blood banks and donation centres are located in urban centres, inaccessible to those in rural areas. The prevalence of transfusion-transmissible infections in the blood supply is higher in LMICs (30 LMIC manuscripts), resulting in high discard rates and increased transfusion risks. Two-thirds of countries have a national blood policy in place, but are often unable to efficiently coordinate and regulate blood services nationwide. To overcome these barriers, some countries have developed innovative solutions. InterpretationThe blood supply in LMICs is of insufficient quantity and safety, and the reasons for these deficits are multifactorial. Addressing blood supply inadequacies requires focused attention at both local and global levels. Political prioritisation and innovative solutions to the blood crisis will be necessary to improve this situation and will require a culturally cognizant, pro-poor, pro-equity approach. Reviewing successful approaches to this crisis employed by some countries can be helpful in charting a way forward. FundingNone.

Prevalence and quantitation of parvovirus B19 DNA levels in blood donors with a sensitive polymerase chain reaction screening assay

Blood donor parvovirus B19 DNA prevalence with sensitive nucleic acid test assays has recently been demonstrated to be higher than that found with assays designed to detect high viral titers in the plasma manufacturing sector. Stored plasma aliquots from 5020 donations collected between 2000 and 2003 at seven US blood centers were tested. Testing was performed with a real-time B19 DNA polymerase chain reaction (PCR; TaqMan, Applied Biosystems) assay with a 50 percent limit of detection (LOD) of 1.6 IU per mL (95% confidence interval [CI], 1.2-2.1 IU/mL) and a 95 percent LOD of 16.5 IU per mL (95% CI, 10.6-33.9 IU/mL). Confirmation and quantitation of B19 DNA was accomplished by retesting of two additional subaliquots. Confirmed-positive specimens were tested for the presence of anti-B19 immunoglobulin M (IgM) and IgG with FDA-licensed assays. B19 DNA prevalence was 0.88 percent (95% CI, 0.64%-1.2%). Among the 23 donations with B19 DNA titers of at least 20 IU per mL, the median DNA concentration was 105 IU per mL with an interquartile range of 42 to 481 IU per mL; the highest value was 1869 IU per mL. All B19 DNA-positive donations were positive for the presence of IgG and 10 (23%) were also positive for the presence of IgM; IgM seropositivity was associated with increasing DNA levels (p = 0.0013). Low-level B19 DNA was detected in nearly 1 percent of donations. The 23 percent of DNA-positive donations with both IgM and IgG B19 antibody most likely represent acute resolving infection, whereas those with IgG but no IgM are most consistent with a more chronic and possibly persistent phase of B19 infection.

Integration of nucleic acid amplification test results into hepatitis C virus supplemental serologic testing algorithms: implications for donor counseling and revision of existing algorithms

The routine use of hepatitis C virus (HCV) nucleic acid amplification testing (NAT) donor screening assays has provided an opportunity for revision of the current HCV supplemental testing algorithm, which requires that recombinant immunoblot assay (RIBA) be performed on every HCV enzyme immunoassay (EIA)-repeat-reactive donation. The FDA has approved variance requests to use a new algorithm that eliminates the need to perform RIBA when HCV NAT results are reactive. Data are provided in support of this new algorithm. HCV EIA (including signal-to-cutoff optical density ratio), RIBA, and NAT data were compiled from 33.2 million donations screened over an approximately 4-year period by the American Red Cross and Blood Systems Laboratories. Further, donations having specific combinations of HCV EIA, RIBA, and minipool (MP) NAT results were evaluated, with more sensitive individual-donation (ID) NAT, to construct improved counseling messages for donors. Of 47,041 EIA-repeat-reactive donations, 49.3 percent were RIBA-positive, 17.1 percent RIBA-indeterminate, and 33.5 percent RIBA-negative. NAT-reactive rates were 79.2, 2.5, and 0.18 percent for RIBA-positive, -indeterminate, and -negative donations, respectively. The new algorithm classified an additional 1 percent of donations as HCV-infected while at the same time detecting all infections classified as HCV-infected under the current algorithm. An additional 2.4 percent of RIBA-positive, MP NAT-nonreactive donations were reactive when a frozen-thawed aliquot was retested by ID NAT. Integrating HCV NAT results with RIBA results for purposes of donor notification allows more appropriate counseling messages to be given to EIA-repeat-reactive donors. The new HCV supplemental algorithm is an acceptable alternative to the current algorithm because it provides equivalent or superior accuracy in formulating donor counseling messages and may also result in reduced costs and more timely notification of infected donors.

Lack of correlation between HBsAg and HBV DNA levels in blood donors who test positive for HBsAg and anti‐HBc: implications for future HBV screening policy

Studies showing a significant correlation between hepatitis B surface antigen (HBsAg) and hepatitis B virus (HBV) deoxyribonucleic acid (DNA) levels have focused on the HBV seroconversion window period. HBsAg levels relative to HBV DNA results in 200 HBsAg-positive, anti-hepatitis B core antigen (HBc)-reactive blood donations were analyzed using quantitative polymerase chain reaction (PCR) (detection limit 400 copies/mL), two research PCR assays with increasing sensitivities (65 copies/mL and 1.3 copies/mL, respectively), and a quantitative HBsAg assay; HBsAg and HBV DNA levels were correlated with HBV serologic profiles; and the potential for replacing HBsAg screening with nucleic acid testing (NAT) was analyzed. Serologic profiles for over 90 percent of the donor samples were consistent with chronic HBV infection. Correlation between HBsAg and HBV DNA concentrations was weak (correlation coefficient = 0.33). Thirty-six percent (72/200) of donor samples had DNA levels under 400 copies per mL. Retesting of the 72 samples by more sensitive PCR assays showed that 60 out of 200 (30%) were positive by PCR with sensitivity of 65 copies per mL, whereas 6 out of 200 (3%) required PCR sensitivity of 1.3 copies per mL for positivity. Three percent (6/200) were negative by all three NAT assays. HBV DNA levels in HBsAg-positive, anti-HBc-reactive blood donations can be extremely low. About 6 percent of donations would be negative by current minipool HBV NAT methods. About 3 percent of donations would remain undetected by sensitive single-donor NAT. These results indicate caution in any consideration of dropping HBsAg screening.

Lowering the hemoglobin cutoff for female plateletpheresis donors.

The standards of the American Association of Blood Banks describe a minimum hemoglobin level of 12.5 g per dL for apheresis donors. Until 1995, the authors' institution accepted occasional platelet donors with a lower minimum hemoglobin (11.5 g/dL), if accompanied by medical director approval. All donation records from a 6-month period before 1995 were retrospectively reviewed to determine whether this lower hemoglobin cutoff adversely affected either the safety of the platelet donation process or donors' subsequent hemoglobin levels. Of 450 donations, 56 (12%, Group 1) were from donors with hemoglobin concentrations between 11.5 and 12.4 g per dL (2 donations from 1 man; 54 donations from 45 women). The remaining 394 donations (88%, Group 2) came from donors with hemoglobin concentrations > or = 12.5 g per dL (216 donations from 118 men; 178 donations from 119 women). The frequency of donor reactions was acceptable (Group 1, 11%; Group 2, 6%); 2 percent of donations by Group 1 donors and 1 percent by Group 2 donors were terminated because of these reactions. Of 46 donors in Group 1, 30 returned to donate platelets again at a later time; at least once, 23 (77%) had a hemoglobin > or = 12.5 g per dL. Ten donors in Group 1 returned for additional donations within 56 days; no meaningful decrease in hemoglobin levels occurred. A hemoglobin cutoff of 12.5 g per dL during the study period would have excluded 1 percent of platelet donations by men and 23 percent by women. The data demonstrate that the lower hemoglobin cutoff of 11.5 g per dL is a safe and relevant threshold for accepting female plateletpheresis donors and would allow more participation by women in blood donor programs.

BLOOD OF LOVED ONES IS NO SAFER THAN GENERAL SUPPLY, STUDY FINDS

SAN FRANCISCO, Nov. 11 (AP)—Blood donated by family members and friends is more likely to carry hepatitis and some other diseases than is blood from anonymous donors, a Government study has found... The study, financed by the National Institutes of Health, is the first large-scale examination of the safety of directed donations, Mr. Williams said. It involved examination of the records of 1,099,341 donations by 699,702 donors in Los Angeles, Oklahoma City, Detroit, San Francisco and the Baltimore-Washington area. One screening test showed that 2.6 percent of donations from friends and relatives were infected with hepatitis B, compared with 1.8 percent of blood-bank donations, Mr. Williams said. Donations from friends and family members were also more likely to be contaminated with hepatitis C, syphilis and a virus HTLV-1, that can cause cancer.

Surrogate testing for non-A, non-B hepatitis in Queensland, Australia: An ALT microtitre tray method for screening blood donors

The estimation of plasma alanine aminotransferase (ALT) has been proposed as a surrogate test to identify potential non-A, non-B hepatitis carriers in blood donor populations. This report describes an ALT screening procedure which uses wells of microtitration trays as reactant vessels. The method utilizes a rate reading photometer, is economical and conveniently fits into the routine workflow. Within-batch and between-batch precision was 4.1% and 6.3% at enzyme concentrations of 49 IU/I. Results of testing 29,675 healthy blood donors gave values which ranged between 1.0 IU/I and 214 IU/I. A study of 762 donations showed a significant difference in mean ALT values between males and females (p less than 0.01). When a cut-off value of 46 IU/I was used, 2.5 percent of donations were considered unsuitable for transfusion. The medico-legal implications that may arise from the introduction of this screening test into the routine work flow are discussed.