The Hb levels of prospective blood donors are usually determined using a finger prick test. A new noninvasive Hb device has the advantage of not causing any sampling pain. The purpose of this study was to evaluate the accuracy of the noninvasive Hb sensor and to compare its measurements with those of a currently used portable hemoglobinometer.
Hb was measured using a noninvasive Hb sensor (NBM-200; OrSense, Israel), a portable hemoglobinometer (HemoCue; HemoCue AB, Sweden), and an automated hematology analyzer (LH500; Beckman Coulter, USA). The correlations between Hb measurements taken by the NBM-200 and HemoCue with those by an automated hematology analyzer were assessed using intraclass correlation coefficients (ICCs). Hb measurements were compared among 3 different Hb level groups.
The mean Hb values of 506 blood donors were 14.1 g/dL by the NBM-200, 14.0 g/dL by the LH500, and 14.3 g/dL by the HemoCue. The correlation between the LH500 and the NBM-200 was substantial (ICC=0.69), while that between the LH500 and the HemoCue agreed almost perfectly (ICC=0.86).
The possibility to judge to be eligible for donors who are ineligible to donate was substantial when using NBM-200. Even though the NBM-200 has the apparent advantage
of noninvasiveness, its use in pre-screening should be given meticulous attention. Since pre-donation testing is crucial to protecting donors' health, complete evaluation of the instrument should be performed prior to use.
Blood donors; Donor selection; Hemoglobin; Safety management
Voluntary blood donation is not satisfactory all over India. In India, about 55% of donation is through voluntary non-remunerated blood donors (VNRBD). However, about one third already motivated blood donors are deferred due to stringent screening criteria, either temporarily or permanently. The temporarily deferred donors could be a good source of blood donation after deferral period.
The present study is carried out to know retrieval of blood donors those who are deferred temporarily.
The present study is carried out in the Regional Blood Transfusion Centre of Western India. All donors screened as per the guideline and deferred donors are categorized as temporary and permanently deferred donors.
Materials and Methods:
From temporarily deferred donors, reason for deferral is considered. As per reason of deferral, time duration for recalling the donor is defined. Based on this, donor is called back to donate again.
Chi-square test is applied.
A total of 33% donors were deferred either temporarily or permanently. In the repeat donors (5.32%) deferral rate was significantly higher than first time (1.32%) donors. Significant female preponderance was observed (15.05% vs 2.51%). Majority of temporarily deferred donors were less than 40 years of age (80.80%), graduate (82.90%), from low income group (62.90%) and profession was service (48.10%).
Low hemoglobin (78.30%) was the most common reason of temporary deferral, both in first time and repeat donors (71.00%). Efforts to increase the hemoglobin in the repeat donors will improve the donor retention and overall blood safety can be increased.
Donor return; hemoglobin; retrieval; temporary deferral; voluntary non-remunerated blood donors/ blood donor
Blood donor selection is important to ensure the safety of both donors and recipients. There is a paucity of data on reasons for blood donor deferral in Ivory Coast. The aim of this study was to identify the reasons for predonation deferral at a blood collection site at General Hospital, Yopougon Attié in Abidjan.
MATERIALS AND METHODS
The investigators conducted a retrospective audit of data pertaining to donor deferral for blood donors that presented to the general hospital of Yopugon Attié from January 1, 2006 to December 31, 2008.
A total of 10,694 prospective blood donors, presented over the study period, and 24,363 attempts to donate were registered. The majority were repeat blood donors (77.4%). A total of 2618 (10.8%) donors were deferred. The most frequent reason for deferral was a low hemoglobin level (42.5%), with females constituting the majority of those deferred. The second most frequent reason for deferral was a reported change of or new sexual partner (34.3%); male donors were predominant in this group. Additional reasons for deferral included short interdonation interval (4.6%) and reactivity for a screened biomarker (2.3%).
Although the rates for permanent and temporary deferral rates are similar between the Ivory Coast and high-middle income countries, the causes and demographics differ. The reasons for exclusion are preventable through awareness and education of prospective blood donors.
Anemia is an early indicator of many diseases, yet blood donors with low hematocrit (Hct) often receive inadequate information about its medical importance. We sought to understand the types of information that are and should be provided to these donors.
STUDY DESIGN AND METHODS
Two companion studies were performed. The first investigated blood center practices for care of donors with low Hct including deferral length, information provided, and cutoff values used when referring donors for medical attention. The second was a randomized prospective pilot study comparing behavior of deferred donors receiving an “older” pamphlet providing a list of iron-rich foods or a “newer” pamphlet providing descriptions of common causes of anemia and advice for seeking medical attention.
More than 70% of centers defer donors for 1 day. Only 6% defer donors for more than 2 weeks. Most centers provide written and/or verbal information about low Hct. Only 35% have a cutoff value defining significant anemia that requires additional medical attention. In the study of donors with low Hct, significant disease was identified within 3 months after deferral in 2 of 104 subjects: metastatic lung cancer and acute lymphocytic leukemia. Only donors receiving the newer pamphlet reported that it “definitely improved” their ability to speak with their doctor about anemia.
The diagnosis of anemia in blood donors may be an indicator of significant undiagnosed disease. There are wide variations in how centers care for and educate donors with anemia. Donors with anemia should be provided improved and consistent educational information.
To study the main causes of predonation deferral of potentially healthy prospective blood donors in a University Hospital Blood Bank unit, and to make recommendations accordingly.
A retrospective review of the main causes of predonation deferral of blood donors in King Fahd Hospital of the University (KFHU) Al-Khobar, was carried out. Records of all predonation deferrals from 1st January 1996 to 31st December 2003 were reviewed and analyzed.
A total of 33,900 potential blood donors came to donate blood during the study period. A total of 6508 donors (19.2%) were deferred for various reasons. Analysis of the causes of deferral showed the following as the most common reasons in rank order: (1) recent ingestion or taking of counter-indicative medications; (2) low hematocrit level; (3) underweight; (4) abnormally high pulse rate; (5) low blood pressure; (6) temperature above 37.5°C; (7) High blood pressure; (8) presenting for donation too soon i.e. less than 8 weeks after the previous one; (9) age below or above the accepted limit; (10) a previous serological positive result; (11) general appearance; (12) abnormally low pulse rate.
Conclusion and Recommendations:
It is important to provide donors with a clear message on their deferral status. Increased public education about blood donation and the common causes of donor deferral may lower deferral rates and prevent a negative impact on the donor himself as well as on subsequent blood donations. Public education is needed also to help recruit as many volunteer donors as possible.
Prospective blood donors; Donor screening; Pre-donation deferral
Deferrals lead to loss of precious whole blood donors (WBD) and blood units available for transfusion purposes. Knowledge of rate and causes of donor deferral can guide the recruitment strategy for WBD.
To find the incidence and causes of deferral in Indian WBD and apply relevant findings to modify recruitment strategy for blood donors.
Materials and Methods:
Data for WBD presenting for donation in a blood center and outdoor camps over one and half year were analyzed retrospectively. National guidelines were used for selection and deferral of WBD.
736 (11.6%) WBD were deferred out of 6357 presenting for donation during the study period. Most (69.8%) of the donors were deferred on physical examination and hemoglobin (Hb) testing. Most common reasons for deferral were low Hb (55.8%), abnormal blood pressure (11.1%), medication (6.9%) and underweight donors (2.9%). Significantly more volunteers were deferred than relative donors (13.97% vs 5.80%; P<0.000). Females were found to have higher deferral rate than males (53.5% vs 6.9%; P=0.000) and higher odds ratio for deferral (15.4). Donors older than 40 years of age had significantly higher chance of being deferred (P<0.05).
Discussion and Conclusion:
It is important to determine the rate and causes of WBD deferral to guide the recruitment and retention efforts at local, regional, and national level.
Anemia in blood donors; blood donor deferral; deferral criteria; deferral reasons; donor rejection; hypertension in blood donors; medication history in blood donors
Iron depletion/deficiency in blood donors frequently results in deferrals for low hemoglobin, yet blood centers remain reluctant to dispense iron replacement therapy to donors.
Study Design and Methods
During a 39-month period, 1236 blood donors deferred for hemoglobin <12.5 g/dL and 400 non-deferred control donors underwent health history screening and laboratory testing (CBC, iron studies). Iron depletion and deficiency were defined as ferritin of 9–19 mcg/L and <9 mcg/L in females and 18–29 mcg/L and <18 mcg/L in males. Deferred donors and iron-deficient control donors were given a 60-pack of ferrous sulfate 325 mg tablets, and instructed to take one tablet daily. Another 60-pack was dispensed at all subsequent visits.
In the low hemoglobin group, 30% and 23% of females and 8% and 53% of males had iron depletion or deficiency, respectively, compared with 29% and 10% of females and 18% and 21% of males in the control group. Iron depleted/deficient donors taking iron showed normalization of iron-related laboratory parameters, even as they continued to donate. Compliance with oral iron was 68%. Adverse gastrointestinal effects occurred in 21% of donors. The study identified 13 donors with serious medical conditions, including eight with GI bleeding. No donors had malignancies or hemochromatosis.
Iron depletion or deficiency was found in 53% of female and 61% of male low hemoglobin donors, and in 39% of female and male control donors. Routine administration of iron replacement therapy is safe, effective, and prevents the development of iron depletion/deficiency in blood donors.
Voluntary donation is a key issue in transfusion medicine. To ensure the safety of blood transfusions, careful donor selection is important. Although new approaches to blood safety have dramatically reduced the risks for infectious contamination of blood components, the quality and the availability of blood components depend on the willingness to donate and the reliability of the information given by the donors about their own health, including risk behavior. As donors who are deferred by the blood bank will be less motivated to return for donation, it is important to reduce the number of deferrals. The aims of the present study were to investigate the reasons for deferral of registered donors coming to the blood bank for donation, in order to identify areas of importance for donor education—as these deferrals potentially could be avoided by better donor comprehension. Deferral related to testing of donors is not included in this study as these deferrals are dependent on laboratory results and cannot be indentified by questionnaire or interview. Data were collected from all blood donors in a period for 18 months who came for blood donation at a large university hospital in Norway. 1 163 of the 29 787 regular donors, who showed up for donation, were deferred (3.9%). The main reasons were intercurrent illness (n = 182) (15.6%), skin ulcers (n = 170) (14.6%), and risk behaviour (n = 127) (10.9%). In a community, intercurrent illnesses, skin ulcers, and potential risk behavior are the most frequent reasons for deferral of regular donors. Strategized effort on donor education is needed, as “failure to donate” reduces donor motivation.
The minimum hemoglobin cutoff for blood donation in India is 12.5 gm% for both male and female donors and the minimum donation interval is 3 months. Donation of one unit of blood results in decrease in hemoglobin by 1 gm% and loss of 200–250 mg of iron. Donor deferral due to anemia is one of the major reasons of temporary rejection of blood donors. In the absence of further workup or advise, it results in loss of valuable donor base.
Aim and Objective:
To provide baseline information regarding the prevalence and spectrum of anemia in prospective blood donors to help plan a future strategy for donor management.
Materials and Methods:
Hemoglobin testing of donors was performed using Hemocue and Copper sulfate specific gravity method. Ethylene diamine tetraacetic acid sample of all the donors who failed either or both the screening tests was tested on automated analyzer for evaluation of hemoglobin and red blood cell indices.
Of all the donors, 15.5% were deferred due to anemia. Prevalence of anemia in prospective blood donors was 1.8%. It was significantly higher in female donors compared with male donors (34.2% vs 1.2%). The most common type of anemia was normocytic normochromic.
Anemia; donor deferral; hemoglobin
The objective was to determine the basic hematological parameters of remunerated blood donors in Benin City and to compare them with those of voluntary donors.
Materials and Methods:
This is a prospective study conducted in a tertiary health facility in Benin City. Pretransfusion samples were obtained from blood bags after gentle mixing and analyzed for hematological parameters. Samples were analyzed using the hematology autoanalyzer MODEL SYSMEX KN21.
A total of 215 samples were obtained comprising 160 remunerated (paid) and 55 voluntary donor samples. In the paid donors, the mean hemoglobin concentration (Hb) and hematocrit (HCT) 7.7±2.9 and 28.8±8.5 respectively. This was significantly lower than those of voluntary donors who had 13.9±1.2 and 42.2±3.3 with P < 0.001. The mean values of the red cell counts (RBC), white cell counts (WBC), mean cell volume (MCV), mean corpuscular hemoglobin (MCH), and mean corpuscular hemoglobin concentration (MCHC) were significantly lower in paid donors as P-values were < 0.001. MCV was significantly low but not compared to the other parameters as P=0.04. There was no significant difference in the platelet count.
Paid donors in Benin City have significantly lower hematological parameters than controls.
Benin; hematological parameters; remunerated donors; voluntary donors
The consequences of temporary pre-donation donor deferrals are unsatisfactorily understood. Previous studies have found that deferral negatively impacts future return for donation in both first time and repeat donors. However, the applicability of these findings across centers has not been established.
Using a cohort design, presenting donors with a temporary deferral in the years 2006 – 2008 in 1 of 6 categories (low hematocrit, blood pressure or pulse, feeling unwell, malaria travel, tattoos/piercing and related exposures, or couldn’t wait/second thoughts) were passively followed for up to a 3-year period for the time to first return after the expiration of the deferral at 6 US blood centers. Time-to-event methods were used to assess return following the receipt of each deferral. We also analyzed which donor characteristics are associated with return following temporary deferral using multivariable logistic regression.
Of 3.9 million donor presentations, 505,623 resulted in deferral in 1 of the 6 categories. Low hematocrit was the most common deferral, had the shortest median time to return, and largest cumulative number of donors returning. Deferrals of shorter duration had better return. Longer term deferrals (up to 1-year in length) had the lowest cumulative return which did not exceed 50% during the study period for malaria travel or tattoo/piercing and related exposures. In multivariable logistic regression modeling, return following deferral was associated with previously identified factors such as repeat donor status, older age, and higher educational attainment regardless of the type of deferral. In addition, return was associated with having been born in the USA, Asian race/ethnicity, and donation at fixed sites regardless of the type of deferral.
The category of temporary deferral influences the likelihood of future return, but the demographic and donation factors associated with return are consistent regardless of the deferral.
The safety of the blood supply is ensured through several procedures from donor selection to testing of donated units. Examination of the donor deferrals at different centers provides insights into the role that deferrals play in transfusion safety.
A cross-sectional descriptive study of prospective allogeneic blood donors at three large blood centers located in São Paulo, Belo Horizonte and Recife, Brazil from August 2007 to December 2009 was conducted. Deferrals were grouped into similar categories across the centers, and within each center frequencies out of all presentations were determined.
Of 963,519 prospective blood donors at the three centers, 746,653 (77.5%) were accepted and 216,866 (22.5%) were deferred. Belo Horizonte had the highest overall deferral proportion of 27%, followed by Recife (23%) and Sao Paulo (19%). Females were more likely to be deferred than males (30% versus 18%, respectively). The three most common deferral reasons were low hematocrit/hemoglobin (Ht/Hb), medical diagnoses and higher-risk behavior.
The types and frequencies of deferral vary substantially among the three blood centers. Factors that may explain the differences include demographic characteristics, the order in which health history and vital signs are taken, the staff training, an the way deferrals are coded by the centers among other policies. The results indicate that blood donor deferral in Brazil has regional aspects that should be considered when national policies are developed.
blood donation; deferred donors; deferral reasons
Deferral for travel to malaria-endemic areas excludes many blood donors in the United States. Most transfusion-transmitted malaria is associated with lengthy residence in malaria-endemic areas rather than routine travel. This study compares the impact of existing deferral requirements to the risk that a presenting donor with malaria travel history harbors malaria parasites under current and hypothetical alternate regulations.
STUDY DESIGN AND METHODS
Deferred donors from six blood centers were sampled to estimate a national cohort of donors deferred annually for malaria travel to different geographic regions. Risk for malaria infection following travel to each region, and distribution of incubation periods for each malaria species were estimated for U.S. travelers. Region-specific travel risks were used to estimate the risk that a presenting blood donor with malaria travel might asymptomatically harbor malaria parasites at different intervals following return to the United States.
Travel to Africa presents risk for malaria infection >1000 times that of travel to malaria-endemic parts of Mexico, yet Mexico accounts for >10 times as many deferred donors. Shortening the deferral period from 12 to 3 months for travelers to Mexico increases the risk of collecting a contaminated unit by only 1 unit per 57 years (sensitivity analysis, 1 every 29 - 114 years), at annual gain of >56,000 donations.
This study provides the first systematic appraisal of the U.S. requirements for donor qualification regarding travel to malarial areas. Consideration should be given to relaxing the guidelines for travel to very low-risk areas such as Mexico.
Plasmodium; malaria; blood donor; deferral; malaria travel; transfusion transmitted disease
It is well known that quite a large number of apparently healthy donors are not able to donate blood successfully because of varied reasons.
We want to analyze the rate and various reasons for deferrals.
Materials and Methods:
A retrospective analysis of records of the donors, for 3 years, from January 2005 to December 2007 was done, in order to find out the rate and causes of deferral in four categories of age groups, both in male and female, in our Transfusion Medicine Centre, Bangalore, India.
There were 16,706 donors, of which 976 donors were deferred (5.84%) for various reasons. Of the 16,706 donors registered for donation, females constituted only 11.27%. And deferral rate was about five times more for female (19.85%) compared to male (4.06%). The three most common reasons for deferral in female were low hemoglobin levels, low body weight, and hypotension. The deferral rate was higher in the age group of 18-25 years and most common cause was low hemoglobin level. In male, the three most common reasons for deferral were hypertension, under weight, and low hemoglobin levels. The deferral rate varied from 4 to 15% as reported in the literature. The most common cause of deferral in our study and in several studies available in the literature is the same.
Blood donor; deferral; permanent; temporary
Contemporary descriptions of blood donor demographics are of value in formulating recruitment and retention strategies that help assure an adequate blood supply. The demographics of successful (SV), unsuccessful (UV), meaning a non-useable unit, and deferred (DV) donor visits over a 4-year period were investigated using Retrovirus Epidemiology Donor Study (REDS)-II databases.
Data came from six US blood centers participating in REDS-II. This analysis focused on demographic factors recorded for each SV, UV, and DV. Fourteen deferral categories were created that included Low Hct/Hgb; Feeling Unwell; Malaria Travel; Malaria Other; Couldn't Wait; BP/Pulse; Medical Diagnosis; Medication; Test Results; Higher Risk Behavior; vCJD; CJD; Needle Exposure/Tattoo and Other. Rates per 10,000 donor presentations were determined for each category globally and for six sub-categorizations (first time or repeat donor status, gender, race/ethnicity, age, education, and fixed or mobile donation location). Deferral rates were also calculated on simultaneous stratifications of donor status, gender, and race/ethnicity.
Out of 5,607922 donor presentations there were 4,553,145 SV (81.2%), 302,828 UV (5.4%) and 751,381 DV (13.4%). Overall rates of deferral ranged from 0.6 per 10,000 presentations for CJD/Human Growth Hormone/Dura Mater exposure to 777 per 10,000 presentations for Low Hct/Hgb. Deferral rates were remarkably different by first time or repeat donor status, gender, race/ethnicity, and by other demographics. The highest overall deferral rate was 3953 per 10,000 presentations, or nearly 40% in first time, female, Asian donors and the lowest rate was 5.6% in repeat, male, White donors.
Successful donation visits according to demographic characteristics need to be placed within the context of donation attempts that are unsuccessful and donors who are deferred. The deferral rates indicate that the burden of donor deferral is high. Efforts to expand the diversity of the donor base through recruitment of minority donors may bring additional challenges because certain deferral reasons were proportionally much higher in these groups.
Syphilis screening of blood donors is a common practice worldwide, but very little is known about the meaning of a positive serologic test for syphilis in blood donors and the risk profile of these donors. The aim of this study was to determine the demographic characteristics and risk behaviors of blood donors with recent and past syphilis and their implications for blood bank testing and deferral strategies.
STUDY DESIGN AND METHODS
Demographic characteristics, category of donation, number of previous donations, sexual behavior, and history of sexually transmitted diseases were reviewed comparing blood donors with recent and past syphilis from January 1, 1999, to December 31, 2003.
A total of 2439 interviews were reviewed, including 2161 (88.6%) donors with past and 278 (11.4%) with recent syphilis infection. Factors associated with recent infection included younger age (≤20 years odds ratio [OR], 36.5; 95% confidence interval [CI], 15.8–84.1), two previous donations (OR, 2.7; 95% CI, 1.9–3.9), male-male sex (homosexual OR, 8.2; 95% CI, 3.2–20.8; and bisexual OR, 11.4; 95% CI, 3.6–36.3), two or more partners in the past 12 months (OR, 2.3; 95% CI, 1.3–4.0), symptoms for syphilis (OR, 4.5; 95% CI, 2.8–7.1), and human immunodeficiency virus (HIV) seropositivity (OR, 39.6; 95% CI, 4.6–339.8). Community donors were also associated with recent syphilis infection (OR, 1.5; 95% CI, 1.2–1.9) compared to replacement donors.
Sexual history, including male-male sex and multiple partners, were strongly associated with recent syphilis infection, which in turn was strongly associated with HIV. Continuous and vigilant surveillance that includes assessing sexual history and other factors associated with syphilis are needed to guide blood safety policies.
Approximately 10% of attempted blood donations are not allowed because of low hemoglobin deferral.
STUDY DESIGN AND METHODS
Low hemoglobin deferrals were tracked in over 715,000 whole blood donors at six blood centers across the United States. A multivariable logistic regression model was developed to comprehensively assess demographic correlates for low hemoglobin deferral.
Demographic factors significantly associated with low hemoglobin deferral include female gender (11 times greater odds than males), increasing age in men (men over 80 have 29 times greater odds than men under 20); African American race (2–2.5 times greater odds than Caucasians); Hispanic ethnicity in women (1.29 times greater odds than Caucasian women) and weight in men (men under 124 pounds have 2.5 times greater odds than men over 200 pounds). Interestingly, increasing donation frequency is associated with decreased odds for low hemoglobin deferral (women with 1 donation in the previous 12 months have 2 times greater odds than those with 6 donations).
Low hemoglobin deferral is associated with female gender, older age, African-American race/ethnicity and lower body weight in men. An inverse association with donation frequency suggests a selection bias in favor of donors able to give more frequently. These data provide useful information that can be utilized to manage blood donors in order to limit low hemoglobin deferrals and assist in policy decisions such as changing the hemoglobin cut-off or permissible frequency of donation. They also generate hypotheses for new research of the causes of anemia in defined groups of donors.
Blood donors are at risk of iron deficiency. We evaluated the effects of blood donation intensity on iron and hemoglobin in a prospective study.
Four cohorts of frequent and first time or reactivated blood donors (no donation in 2 years), female and male, totaling 2425 were characterized and followed as they donated blood frequently. At enrollment and the final visit, ferritin, soluble transferrin receptor (sTfR), and hemoglobin were determined. Models to predict iron deficiency and hemoglobin deferral were developed. Iron depletion was defined at two levels: Iron Deficient Erythropoiesis (IDE) [log (soluble transferrin receptor/ferritin ≥ 2.07)] and Absent Iron Stores (AIS) (ferritin < 12 ng/mL).
Among returning female first time/reactivated donors, 20% and 51% had AIS and IDE at their final visit, respectively; corresponding proportions for males were 8% and 20%. Among female frequent donors who returned, 27% and 62% had AIS and IDE, respectively, while corresponding proportions for males were 18% and 47%. Predictors of IDE and/or AIS included a higher frequency of blood donation in the last 2 years, a shorter interdonation interval, and being female and young; conversely, taking iron supplements reduced the risk of iron depletion. Predictors of hemoglobin deferral included female gender, Black race and a shorter interdonation interval.
There is a high prevalence of iron depletion in frequent blood donors. Increasing the interdonation interval would reduce the prevalence of iron depletion and hemoglobin deferral. Alternatively, replacement with iron supplements may allow frequent donation without the adverse outcome of iron depletion.
Donors; Hematology – Red Cells; Blood Center Operations
Travel to malaria risk areas such as Mexico is a common source of donor deferral in Canada. On February 21st, 2011 the deferrable regions in Mexico were revised to permit donation if donors travelled to the state of Quintana Roo, Mexico, a popular ocean-side resort area.
Materials and methods
Canadian travel data and malaria deferral rates since 2007 were plotted to examine trends. Deferral records in one centre were accessed from January to April, 2011 to tabulate travel destinations of deferred donors immediately before and after the change.
Travel to Mexico and the Caribbean accounts for 63% of general population travel, and travel to Mexico has been increasing (P <0.05). Deferral for short-term malaria risk travel has a strong seasonal trend with peaks in the winter and troughs in the summer. Approximately 36,000 fewer donations were lost following the change, a reduction of 37% from the previous year. Deferrals in one centre increased for Caribbean/Central America after the change (P <0.05) consistent with the seasonal trend, but decreased for Mexico (P <0.05).
Deferrals for malaria risk travel are substantial. Careful revision and refinement of risk areas of travel can significantly reduce the burden of deferral.
malaria; Quintana Roo; donor deferral; blood safety
Deferring blood donors who admit to high-risk behavior on questioning are likely to eliminate those in window period for transfusion transmitted infections (TTI). However, many questions have been implemented in some countries as part of donor history questionnaire, based on precautionary principle and not on evidence, and can result in increased donor losses. This study aims to identify effective risk-directed questions having high predictive value, in local context which can form part of blood donor deferral policies. For this, a case control study in a hospital blood bank having donation services was carried out prospectively over a period of three years.
Materials and Methods:
Two hundred and twenty donors, who were repeatedly reactive for HBsAg, anti-HCV, anti-HIV with EIA, and syphilis with TPHA, were the cases. Eight hundred and eighty four controls were the donors who tested negative for all TTI test. All donors answered seven hepatitis risk directed questions and their responses and reactivity status for TTI were used for statistical analysis with SPSS ver. 15.
Positive predictive value for history of jaundice at any age for HBsAg was 20%, while PPV for history of surgery in previous six months for both HBsAg and anti-HCVHCV was also around 20%, based on pretest probability of 7%. The post-test probability for these questions was around 30%. Odds ratios with 95% CI did not reveal any significant association of hepatitis with any of seven questions. Donor losses after deferring on basis of two questions were 5.3% per year, while deferral rate after all seven questions was 20%.
Donors should be permanently deferred if there is history of jaundice at any age, while deferral period after surgery should be one year. Other risk-directed questions should not be used to defer donors. Donor deferral policies should be evidence based and questions with proven efficacy should be made part of donor history questionnaire to minimize donor losses.
Blood donor; donor deferral; donor history questionnaire
In the Netherlands about 50% of whole blood donors return to give blood after an invitation to donate. This study aimed to investigate the characteristics of donor return behaviour and to gain insight into the barriers to blood donation reported by the donors themselves.
Materials and methods
A total of 4,901 whole blood donors were invited to donate in week 39 of 2009. Barriers mentioned by donors who informed the blood bank for not donating were registered for 1 month. Logistic regression analyses assessed relevant characteristics of return behaviour, such as age and blood type, in men and women separately.
Of the invited donors, 55% returned to give a donation, whereas 45% did not return. Male donors were more likely to return when they were older, had a higher previous return rate and had no past deferrals. The same pattern was found among women, but was less strong. The main barriers were: time constraints (35%), preference to postpone donation due to general physical problems although being eligible to donate (29%), and being ineligible to donate due to medical deferral criteria (9%).
Specific donor characteristics are associated with return behaviour. Not donating due to time constraints could mean that donors do not feel the urgency of donating blood. Interventions targeted to increase commitment among specific donor groups should be tested further.
blood donors; barriers; return behaviour; donor characteristics
The reasons why deferral from blood donation reduces the likelihood of future return remain unclear. This aim of this study was to investigate possible reasons why deferral has such a dramatic impact on donation patterns.
Qualitative methods were used to explore donors’ motivations to give blood, their experiences of temporary deferral, and their intentions to return once eligible. Semi-structured interviews were conducted with 23 donors in the two weeks following a temporary deferral due to a low haemoglobin concentration. The Framework approach was used to analyse data and identify themes associated with prompt return, ascertained from Blood Service records.
We found that, predominantly, individuals give blood because it represents an easy and convenient way to help others, and provides personal rewards, such as enhancing positive self-concepts and valuable knowledge about health. Deferral disrupts the habit of regular donation, and additionally, introduces an element of practical and emotional hassle to what is generally seen as an undemanding activity. Return after deferral was related to four aspects of a person and their context: an individual’s other obligations, especially parenting; whether donation arrangements were facilitated by a range of supports; the presence of a strong “blood donor” identity; and whether deferral left the donor feeling valued and appreciated.
Aspects of the deferral process need to be improved to ensure individuals feel valued, and continued attention should be given to the convenience of donation, especially for those with competing obligations.
Current European regulations require a deferral period of 6 months or 3 years, depending on the risk of exposure, for prospective blood donors at risk of malaria. This period may be reduced to 4 months if an immunological or molecular genomic test is negative at each donation, but Italian regulations have not adopted this provision. As cases of transfusion-transmitted malaria have been recorded in medical literature in blood donors deferred for 3 years and not tested, the Immunohaematology and Transfusion Centre of the Ca’ Grande Polyclinic Hospital in Milan decided to introduce immunological testing for all donors at risk of malaria.
Materials and methods.
Four hundred and twelve blood donors at risk of malaria, who had lived in a malarial area during the first 5 years of life or for more than 6 consecutive months, were tested for malarial antibodies using an enzyme immunoassay kit. The kit (Malaria EIA, Newmarket, UK) uses four recombinant antigens specific for P. falciparum and P. vivax and with cross-reactivity for P. ovale and P. malariae. The kit detects total immunoglobulin antibodies against P. falciparum and P. vivax and shows 80% cross-reactivity with P. ovale and 67% with P. malariae. Antibody-positive samples were further checked by an immunochromatographic test for P. falciparum, P. vivax, P. ovale and P. malariae antigens and by haemoscopy (thin film and thick smear).
Italian citizens accounted for 16.8% (69/412) of the whole group of donors examined. We found that 8.7% of the donors who were classified as being at risk of malaria were positive for total immunoglobulin antibodies. Only one Italian citizen resulted positive for the test. The positive candidates were deferred from blood donation. None of the antibody-positive donors was confirmed positive by the immunochromatographic test and by haemoscopy.
The introduction of a malarial screening test in the assessment of blood donor eligibility may increase the safety of blood donations, but could further reduce blood availability. If immunological testing were to be accepted nationally as a valid method of assessing the risk of malaria, more than 90% of the donors who are currently deferred for 3 years could be accepted 4 months after their last visit to an endemic area, thus increasing the availability of blood
transfusion-transmitted malaria; enzyme immunoassay; donor’s risk
Iron deficiency is the most common cause of anemia and one of the main factors in the clinical deferral of blood donors. This fact prompted the current study that aimed to determine the prevalence and etiology of anemia in blood donor candidates and to evaluate the hematological screening technique used for the exclusion of these donors.
This was a prospective study that compared two groups (Anemic and Non-anemic). Initially screening for anemia was performed by manually measuring hemoglobin (Bioclin® Kit); the results were subsequently compared with an automated screening method (Coulter T-890). The etiology was investigated by hemoglobin electrophoresis in alkaline and acid pH, Hb A2 dosage and measurement of the ferritin concentration by immunoagglutination. Differences and associations of interest were analyzed using the Yates and McNemar's Chi-square tests and the Fisher, Mann-Whitney, Wilcoxon and Kruskal-Wallis tests.
The deferral rate due to anemia was 4.2%; iron deficiency was identified in 37.5% and beta thalassemia in 9.3% of the excluded candidates. There was a significant discrepancy between the two techniques used to measure hemoglobin with 38.1% of initially deferred donors presenting normal hemoglobin levels by the automated method.
The results show a high rate of blood donors being deferred for anemia and confirm that iron deficiency is the most prevalent cause. The discrepancies found by comparing screening methods suggest that hemoglobin and hematocrit levels should be confirmed before deferring a donor due to anemia; this may increase supplies in blood banks.
Iron deficiency; Blood donors; Donor selection; Anemia
To optimize the planning of blood donations but also to continue motivating the volunteers it is important to streamline the practical organization of the timing of donations. While donors are asked to return for donation after a suitable period, still a relevant proportion of blood donors is deferred from donation each year due to a too low hemoglobin level. Rejection of donation may demotivate the candidate donor and implies an inefficient planning of the donation process. Hence, it is important to predict the future hemoglobin level to improve the planning of donors’ visits to the blood bank.
The development of the hemoglobin prediction rule is based on longitudinal (panel) data from blood donations collected by Sanquin (the only blood product collecting and supplying organization in the Netherlands). We explored and contrasted two popular statistical models, i.e. the transition (autoregressive) model and the mixed effects model as plausible models to account for the dependence among subsequent hemoglobin levels within a donor.
The predictors of the future hemoglobin level are age, season, hemoglobin levels at the previous visits, and a binary variable indicating whether a donation was made at the previous visit. Based on cross-validation, the areas under the receiver operating characteristic curve (AUCs) for male donors are 0.83 and 0.81 for the transition model and the mixed effects model, respectively; for female donors we obtained AUC values of 0.73 and 0.72 for the transition model and the mixed effects model, respectively.
We showed that the transition models and the mixed effects models provide a much better prediction compared to a multiple linear regression model. In general, the transition model provides a somewhat better prediction than the mixed effects model, especially at high visit numbers. In addition, the transition model offers a better trade-off between sensitivity and specificity when varying the cut-off values for eligibility in predicted values. Hence transition models make the prediction of hemoglobin level more precise and may lead to less deferral from donation in the future.
Blood donations; Hemoglobin level; Longitudinal data; Panel data; Transition models; Mixed effects models; Prediction; Kalman filter