Donations For HIV Research Articles

Distribution and Incidence of Blood-Borne Infection among Blood Donors from Regional Transfusion Centers in Burkina Faso: A Comprehensive Study.

ABSTRACTThere is a high prevalence of blood-borne infections in West Africa. This study sought to determine the seroprevalence of blood-borne infections, including hepatitis B virus (HBV), hepatitis C virus (HCV), HIV, and syphilis, in blood donors in Burkina Faso. Blood donors were recruited from 2009 to 2013 in four major cities in Burkina Faso of urban area (Ouagadougou) and rural area (Bobo Dioulasso, Fada N’Gourma, and Ouahigouya). Serology tests including hepatitis B surface antigen, anti-HCV, anti-HIV, and rapid plasma reagin test were used for screening and were confirmed with ELISA. Disease prevalence was calculated among first-time donors. Incidence and residual risk were calculated from repeat donors. There were 166,681 donors; 43,084 had ≥ 2 donations. The overall seroprevalence of HBV, HCV, HIV, and syphilis were 13.4%, 6.9%, 2.1%, and 2.4%, respectively. The incidence rates (IRs) of HBV, HCV, HIV, and syphilis infection were 2,433, 3,056, 1,121, and 1,287 per 100,000 person-years. There was lower seroprevalence of HBV and HCV in urban area than in rural area (12.9% versus 14.0%, P < 0.001; and 5.9% versus 8.0%, P < 0.001), and no difference in HIV (2.1% versus 2.1%, P = 0.25). The IRs of new HBV, HCV, HIV, and syphilis were 2.43, 3.06, 1.12, and 1.29 per 100,000 person-years, respectively. The residual risk was one per 268 donations for HBV, one per 181 donations for HCV, and one per 1,480 donations for HIV, respectively. In conclusion, this comprehensive study from four blood donation sites in Burkina Faso showed high HBV and HCV seroprevalence and incidence with high residual risk from blood donation.

Residual risk of HIV, HCV, and HBV transmission by blood transfusion between 2015 and 2017 at the Regional Blood Transfusion Center of Ouagadougou, Burkina Faso.

IntroductionIn sub-Saharan Africa, the high endemicity of blood-borne infections is a serious threat to transfusion safety. In order to improve transfusion safety, Burkina Faso has undertaken in recent years a reorganization of its blood-transfusion system through the creation of a National Blood Transfusion Center, which is the only blood operator in the whole country. This study aimed to estimate the residual risk of transmission of HIV, hepatitis B virus (HBV), and hepatitis C virus (HCV) by blood transfusion at the Regional Blood Transfusion Center (RBTC) of Ouagadougou.MethodsThis was a retrospective study conducted at the RBTC of Ouagadougou between 2015 and 2017. Prevalence of infectious markers was calculated for first-time donors and incidence rates calculated for repeat donors who had made at least two donations of blood over the study period. Residual risks were estimated for the three viruses (HIV, HBV, and HCV) by multiplying the incidence rate per 100,000 person-years by the respective durations of serological windows.ResultsBetween 2015 and 2017, of a total of 84,299 blood donors, 68,391 (81.13%) were first-time donors compared to 15,908 (18.87%) repeat donors. The seroprevalence of HBV (8.56%) was twice that of HCV (4.40%) and fourfold that of HIV (1.80%). Incidence rates were 1,215, 2,601, and 1,599 per 100,000 donations for HIV, HCV, and HBV, respectively. In contrast, the estimated residual risk for HCV (1 in 213 donations) was double that of HBV (1 in 408 donations) and four times that of HIV (1 in 1,366).ConclusionThe residual risk of transmission of these viruses by blood transfusion remains high in repeat donors. An effective donor-retention and education policy could help to reduce this residual risk.

A nucleic acid amplification repeat testing algorithm reveals high risk of hepatitis B and C transmission with serologic blood screening practice in Punjab, India

BackgroundLack of confirmatory testing of reactive donations for hepatitis C (HCV), B (HBV) and human immunodeficiency (HIV) viruses hampers reliable residual transmission risk analysis in India.Materials and MethodsIn our centre, 39 295 blood donations were tested for HIV Ag/Ab, anti‐HCV and hepatitis B surface antigen (HBsAg) by a variety of ELISAs and in parallel by individual donation nucleic acid amplification technology (ID‐NAT). NAT yields were confirmed by triplicate repeat reactivity in primary test‐tube and fresh frozen plasma (FFP) samples as well as by viral load (VL) testing and supplemental serologic assays.ResultsNAT and serology concordant reactive results included 23 (0·06%), 290 (0·74%) and 254 (0·65%) donations for HIV, HCV and HBV, respectively. Additionally, 15 HCV (1/2620) and 29 HBV (1/1355) seronegative NAT yield donations were confirmed. HBV marker testing identified three (1/13 100) window period (WP), 25 (1/1637) occult HBV infection (OBI) and one anti‐HBs breakthrough infection. ID‐NAT has reduced residual risk of infection from 1/2600 to 1/270 000 for HCV WP, 1/8000 to 1/21 000 for HBV WP and 1/11 000 to 1/66 000 for OBI.ConclusionA NAT repeat test algorithm was instrumental for confirmation of viral infection and revealed high residual risk of hepatitis B and C transmission by the practiced ELISA blood testing.

Residual Risk of Transmission of HIV and Hepatitis B and C by Blood Transfusion in Bukavu in the Democratic Republic of Congo

The aim of this study was to determine the incidence rates of HIV1/2 antibodies, HBV and HCV antibodies among voluntary blood donors and to estimate the residual risk of HIV, HBV and HCV infection among blood donors in Bukavu. We conducted a follow-up cohort study of volunteer blood donors who have made at least two blood donations in Bukavu (DRC) between January 2010 and December 2012. We recorded 2986 volunteer blood donors during the study period. The residual risk of viral transmission associated with the serological window was considered as equals to the incidence rate multiplied by the duration of the serological window period divided by 365. Seroprevalence in volunteer blood donors in Bukavu was 1.1% for HIV 1/2 antibodies, 4.0% for HBs Ag and 2.1% for hepatitis C antibody. The number of conversion between two blood donations (incident cases) were observed is 8, 12 and 37 donors respectively for HIV 1/2, HCV and hepatitis B between 2010 and 2012. Incidence rates reported for 1000 person-years were 11.0 for HIV, 51.7 for HBV and 17.1 for HCV. The residual risk as estimated from the window was 0.6 per 1000 donations or 1/1.515 donations for HIV, 3.1 per 1000 donations or 1/329 for HCV and 7.9 per 1000 donations or 1/126 donations for hepatitis B. The residual risk is high. The screening tests are not enough to ensure safe blood. The reduction of residual risk would be achieved through the effectiveness of preventive measures taken for transfusion chain, before and after the biological qualification of blood donation.

Prévalence et incidence du VIH et de l’hépatite B chez les donneurs de sang et estimation du risque résiduel de transmission du virus VIH et du virus VHB par la transfusion sanguine. Une étude à l’hôpital provincial général de référence de Bukavu, République démocratique du Congo

BackgroundTo estimate the residual risk of transmission of HIV and HBV virus by blood transfusion in Bukavu. MethodsRetrospective cohort study designed for exploratory purposes, which took place in Bukavu (DR Congo) between January 2001 and December 2005, among 3292 blood donors. The incidences were estimated by survival curves and Cox models. The adjusted relative risks with their confidence interval at 95% were derived from Cox models. The residual risk of viral transmission associated with the serological window is equal to the incidence rate multiplied by the duration of the serological window divided by 365. ResultsThe prevalence among blood donors in Bukavu was 1% for HIV and 3.7% for HbsAg. The number of incident cases observed was seven for HIV and 40 for hepatitis B between 2001 and 2005. The incidence rates obtained were 3.57 for 1000 person-years (0.93/1000–6.23/1000) and 25.4 per 1000 person-years (17.6/1000–33.36/1000), respectively for HIV and hepatitis B. The residual risk was 1/4608 donations for HIV or 0.22 (0.02–0.65) and 1/257 donations for HBV or 3.90 (1.20–9.96). Also there were more seroconversions among family blood donors than in volunteer donors. The risk of seroconversion in family donors compared to volunteer donors adjusted for age, sex and residence was 7.09 (3.75–13.39) for HIV and 4.03 (2.63–6.20) for HBsAg. The same result was observed with the survival curves. ConclusionThe prevalences of HIV and HBsAg in Bukavu are lower than in most major cities in sub-Saharan Africa. Residual risks are especially important for hepatitis B.

HIV testing—The perspective from across the pond

The first assay to screen blood donations for HIV was licensed in the USA in 1985. Since then there has been a dramatic increase in the types and numbers of assays available for HIV testing coupled with improvements in the sensitivity and specificity of these assays. However, with this increase in choice the algorithms for the initial diagnosis and confirmation of HIV infection have also increased in diversity and complexity and no uniform algorithm exists. Different regulatory regimes have meant that different assays and assay formats are available worldwide. In the UK we have been fortunate in having access to the so called 4th generation HIV antigen/antibody assays for 10 years. The first 4th generation assay in the US was licensed last year. The availability of this class of assays has led to the development of new algorithms for use in the US market and this paper describes how after many years of diversity the HIV algorithms between the UK and US are now converging.

Response to Zimmermann et al

Dear Editor, We appreciate the opportunity to respond to Zimmermann et al. They refer to publications by Vamvakas [1] and Heuft et al. [2]. Both base their conclusion on mathematical models. Vamvakas presents calculations for additional transfusion transmitted infections (TTI) contracted through platelet transfusions in the United States (US) if pooled platelet concentrate (PPC) would completely replace singledonor apheresis platelet concentrates (APC)[1]. These calculations are based on assumptions which do not all apply for Europe. The calculation is based on the risk of TTI in the US today (1 per 2 135 000 donations for HIV, 1 per 1 935 000 for HCV and 1 per 280 000 for HBV [1]). For the German Red Cross Blood Donor Services, the residual risk for TTI is substantially lower (data 1997–2005): 1 per 4 300 000 donations for HIV, 1 per 10 880 000 for HCV and 1 per 360 000 for HBV [3]. This analysis does not account the effect of anti-HBc testing, which became mandatory in Germany since 2006 and will most likely reduce the risk for HBV. The ‘worst-case scenario’ of Vamvakas who carefully confines the conclusions to the United States assumes that a PPC contains platelets from six whole blood (WB) donations [1]. In many European countries, PPC is pooled from five or four donations. The risk calculation is substantially different if assuming six or four donor exposures per PPC [1]. A significant proportion of APC represents split products so that an infected donor can infect two or even three recipients by one donation and in addition further recipients by subsequent donations during the ‘window period’ because of the potentially short interval of APC donations [4]. A model on GBV-C virus infections takes into account that pooling of a GBV-C RNA positive buffy coat (BC) with a BC containing a GBV-C neutralizing antibody could lead to a non-infectious PPC. A careful sensitivity analysis demonstrates that the number of theoretical GBV-C transmissions depends on the assumed frequency of neutralizing antibodies in the donor population [2]. Many assumptions affect the results of mathematical models and delimit their conclusions [4]. Zimmermann et al. argue that the preparation of PPC affects the quality of red blood cell concentrates (RCC) resulting ‘in a remarkable proportion of underfilled RCC’. The binding German Haemotherapy Guidelines [5] and the ‘Guide to the preparation, use and quality assurance of blood components’ [6] stipulate that at least 95% of the leucocyte-depleted RCC must contain ‡ 40g haemoglobin ⁄unit. The mean haemoglobin of RCC produced by our Blood Service using RCC filtration after BC-removal is 56AE4 g, and only 0AE2% of RCC had haemoglobin content below 40 g ⁄unit, and there is no difference when comparing haemoglobin content in RCC produced from donations without or with concomitant preparation of a PPC. For our Blood Service, we can decline that preparation of PPC by the BC method results in a remarkable proportion of underfilled RCC – and this applies also to other blood services obliged to meet regulatory requirements. Zimmermann et al. refer to the loss of 2,3-DPG during overnight storage at 22 C [7]. Several aspects need to be considered in interpretation of this surrogate parameter: Rapid cooling slowed the loss of 2,3-DPG levels but 2,3DPG levels were undetectable by day 21 irrespective of the initial storage temperature [7]. Wilsher et al. [7] compared processing within 8h versus storage for 24 h at 22 C. In practice, the actual interval between donation and start of processing in most institutions is shorter than 24 h even if overnight storage at 22 C is involved. It has been shown that 2,3-DPG levels return to near normal levels after transfusion [8]. The clinical significance of the observed difference needs to be studied further. Overnight storage at 22 C can increase the efficiency of separation of platelets from WB donations and can reduce bacterial contamination. Zimmermann et al. argue that the processing method affects the levels of platelet-derived cytokines in RCC [9]. It is important to take into account all details of the processing. A high concentration of platelet-derived cytokines was measured in PC prepared with the dock-in Sepacell RBC filter or with platelet-saving WB filters before removing plasma or platelet-rich plasma. In this study, the plasmareduced RCC (still containing platelets) were held overnight at 4 C. Neither a storage at 4 C nor a storage overnight after removal of plasma nor the use of platelet-saving WB filters can be considered as standard procedure for PPC Vox Sanguinis (2010)

Making a blood transfusion safe: vigilance and audit

The transfusion of blood and blood products from one person to another is a highly hazardous process and yet has become a widely used and mostly safe treatment, at least...

Residual risk of HIV, HVB and HCV transmission by blood transfusion between 2002 and 2004 at the Abidjan National Blood Transfusion Center

The assessment of the viral residual risk from blood products is an assessment indicator of the quality management system and of the availability process of these products. Assessments of HIV, HBV and HCV viruses transmission risks through blood transfusion are calculated after the setting of a quality approach at the Abidjan NBTC. The method used estimates the risk of a donation made during a period immunologically silent. The residual risks for HIV, HBV, and HCV viruses have been estimated by multiplying the incidence rate for 100,000 people per year by the respective durations of the serological windows. The data received from the Abidjan Center's information processing system (Progesa 4.4d of MAK SYSTEM) go from 2002 to 2004 period. The residual risks are 1/5780 donations for HIV and 1/406 donations for the HCV, then 1/383 donations for the HBV. The residual risk for the HIV is almost four times reduced compared to that of 1997. The results show not only the importance of the transmission risk of HIV, HBV and HCV viruses through blood products, but also the necessity to set a quality management system in endemic countries of Sub-Saharan Africa.

Trends in risk of transfusion-transmitted viral infections (HIV, HCV, HBV) in France between 1992 and 2003 and impact of nucleic acid testing (NAT)

Monitoring trends in residual risk of transfusion-transmitted viral infections is important to assess improvements in blood safety and to adapt the risk reduction policies. These trends were analysed in France over 4 periods of 3 years (1992-1994, 1995-1997, 1998-2000 and 2001-2003). The 2001-2003 estimates were compared to the results of HIV-1 and HCV NAT implemented on all blood donations in July 2001. Due to improvements in donor recruitment and selection, continuing progress in screening assays, and preventive measures taken in the community to control infections, a significant decrease was observed in residual risks for HIV, HCV and HBV between 1992 and 2003. The residual risk is currently extremely low: for the 2001-2003 period, this risk was estimated at 1 in 3.15 million donations for HIV, at 1 in 10 million for HCV and at 1 in 640,000 for HBV. Of the 6.14 million donations screened with NAT between July 2001 and December 2003 in France, 2 HIV-positive and 3 HCV-positive donations were discarded thanks to NAT, representing a yield of 1 in 3.07 million for HIV and 1 in 2.05 million for HCV. These results show the limited benefit of NAT and suggest that its cost-effectiveness is poor.

Trends in residual risk of transfusion-transmitted viral infections in France between 1992 and 2000.

Monitoring trends in residual risks of transfusion-transmitted viral infections (HIV, HTLV, HBV, and HCV) is important to assess improvements in blood safety. In France, theses trends were analyzed between 1992 and 2000. As risk is predominantly associated with the window period, residual risks were estimated by multiplying incidence rates by the durations of the window periods. Incidence rates were calculated from the data collected by the blood transfusion centers belonging to the Transfusion-Transmissible Agents Working Group, which currently collects more than 50 percent of the 2.5 million blood samples donated each year in France. Trend analysis showed a significant decrease in residual risks for HCV (p = 0.01) and HBV (p < 0.001). Although residual risks decreased for HIV and HTLV, the trends were not significant. In 1998 through 2000, residual risks were estimated to be 1 in 470,000 donations for HBV, 1 in 860,000 for HCV, 1 in 1,370,000 for HIV, nil for HTLV, and 1 in 250,000 for the four viruses combined. In France, the current risk of a blood recipient becoming infected with a retrovirus or a hepatitis virus is extremely low. The implementation of NAT in July 2001 is predicted to reduce the residual risk to 1 in 2,700,000 donations for HIV and 1 in 8,300,000 for HCV.

False-Positive HIV Tests in Blood Donor Screening Rare Events

Ensuring a safe blood supply requires testing all donations for HIV, although donors constitute a low-prevalence population. False-positive tests are an inevitable consequence in this setting. HIV is diagnosed by detecting antibodies on a screening enzyme immunoassay, which is then confirmed by …