Risk Of Transfusion Transmission Research Articles

Increased parvovirus B19 seropositivity in healthy blood donors in India

A core component of every blood program is the supply of safe blood and blood products. The elevated risk of transmission through these products is due to parvovirus B19 (B19V) resistance to the virus inactivation procedures. Our study aimed to screen asymptomatic blood donors for B19V at a tertiary care hospital in Chennai, Tamil Nadu, between September 2020 and June 2021. Sera from 106 healthy blood donors who tested negative for Human immunodeficiency virus (HIV), Hepatitis B surface antigen (HBsAg), Hepatitis C virus (HCV), syphilis, and malaria were tested for anti-B19V IgM and IgG using a qualitative indirect enzyme-linked immunosorbent assay (ELISA). In the study population, 23.5% (n = 25) of donors tested IgM positive, 38.6% (n = 41) tested IgG positive, and 7.5% (n = 8) tested positive for both IgM and IgG. A proportion of 61.3% (n = 65) of the blood donors tested IgG negative, suggesting they had no past B19V infection. B19V DNA was not detected in any of the subjects. The high seroprevalence of IgM indicates that blood donors may have been recently exposed to B19V, potentially posing a risk to immunocompromised individuals and those with hematological stress. Further longitudinal studies with a larger sample size are recommended to better understand the risk of B19V transfusion transmission.

Seroprevalence of Hepatitis B Virus among Blood Donors at National Blood Transfusion and Research Center-Taiz Branch, Yemen

Hepatitis B Virus (HBV) represents one of the most health problems. Almost more than 350 million infected persons were reported universally. Blood transfusion is commonly the most common route of transmission of HBV. Recently, Hospitals in Yemen are increasing demands for blood and blood products due to war injury, anemia, and malnutrition. The risk of transfusion transmission of infection relatively increases. This study aimed to determine hepatitis B virus prevalence among blood donors at the National Blood Transfusion Center -Taiz branch (NBTRC- TB). Data was collected from the National Blood Transfusion and Research Center (Taiz branch) from 1/4/2020 to 16/12/2020. A total of 3174 blood donors donated blood at the center. A descriptive cross-sectional study was conducted on them. Blood donor information was registered at the reception department, and all blood screening tests were performed. Data of HBsAg and total anti-HBc were analyzed statistically by using IBM SPSS version 26. Among 3174 blood donors, male blood donors were 3158 (99.5%) and female blood donors 16 (0.5%). Furthermore, 41 (1.3%) were positive for HBsAg (which all the positive results were for male donors and no positivity were for female donors) while 353 (11.1%) were positive for total anti- HBc Ab which is distributed at ratio of 11% (350) for males and 0.1% (3) for females. On the other hand, the result of HBsAg and total anti-HBc Ab together showed three levels of positivity as the (HBsAg positive / anti-HBc negative) were 12 (0.4%) in which was a low percentage and reversely, the (HBsAg negative/ HBcAb positive) were 316 (10.2%), While the HBsAg positive / anti-HBc positive were 27 (0.9%). So this study shed light on the result of HBsAg negative/ anti-HBc positive which the percentage (10.2%) of which statistically significant (p. value = 0.000) and was the highest result indicates donors with post HBV infection or have low HBV infection. This study showed the high prevalence of post-HBV infection among blood donors. Using both markers HBsAg and total anti-HBc Ab will improve the detection of HBV before blood transfusion.

Dengue virus transmission risk in blood donation: Evidence from Thailand.

Individuals infected with dengue virus (DENV) often show no symptoms, which raises the risk of DENV transfusion transmission (TT-DENV) in areas where the virus is prevalent. This study aimed to determine the evidence of DENV infection in blood donors from different geographic regions of Thailand. A cross-sectional study was conducted on blood donor samples collected from the Thai Red Cross National Blood Center and four regional blood centers between March and September 2020. Screening for DENV nonstructural protein 1 (NS1), anti-DENV immunoglobulin G (IgG), and IgM antibodies was performed on residual blood from 1053 donors using enzyme-linked immunosorbent assay kits. Positive NS1 and IgM samples indicating acute infection were verified using four different techniques, including quantitative real-time (q) RT-PCR, nested PCR, virus isolation in C6/36 cells, and mosquito amplification. DENV IgG seropositivity was identified in 89% (938/1053) of blood donors. Additionally, 0.4% (4/1053) and 2.1% (22/1053) of Thai blood donors tested positive for NS1 and IgM, respectively. The presence of asymptomatic dengue virus infection in healthy blood donors suggests a potential risk of transmission through blood transfusion, posing a concern for blood safety.

Absence of evidence of transfusion transmission risk of Creutzfeldt-Jakob disease in the United States: Results froma 28-year lookback study.

For many years, there has been concern about the risk of transmission of classic forms of Creutzfeldt-Jakob disease (CJD) by blood transfusion, particularly after the recognition of such transmission of variant CJD (vCJD). We report on a 28-year lookback study of recipients of blood from donors who subsequently developed CJD. Patients with diagnosed CJD and a history of blood donation were identified. Blood centers were asked to provide information about the distribution of the donations and consignees were requested to provide information about the recipients of the donations. Vital status of each available recipient was determined and, if deceased, the reported cause(s) of death were obtained primarily from the National Death Index. All recipients included in the study database contributed person-time up to the last recorded review of vital status. There were 84 eligible donors who gave 3284 transfusable components, and it was possible to evaluate 1245 recipients, totaling 6495 person-years of observation. The mean observation period per recipient was 5.5 years with a maximum of 51 years. No case of CJD or prion disease was reported among the recipient population. The study suggests that CJD may not be transfusion-transmissible, a position in agreement with similar findings from two similar European reports amounting to an overall observation period of 15,500 person-years. These studies have supported the conclusion that the risk, if any, of transmission of CJD by blood products is extremely small and remains theoretical.

Efficacy of combined HBsAg, anti-HBc and anti-HBs screening in minimizing transfusion transmission risk of hepatitis B infection in low resource setting

BackgroundHepatitis B Virus (HBV), and occult Hepatitis B in particular, is a major concern in the transfusion scenario, especially in endemic countries. This study attempted to estimate the prevalence of occult Hepatitis B infection (OBI) among voluntary blood donors in Maharashtra and to evaluate the role of combined screening strategy with implications in minimizing the current transfusion risks of seropositive OBI. MethodsDonor samples were collected from 80 eligible blood banks from various districts of Maharashtra between 2014 and 2017. ELISA based screening of HBsAg, anti-HBc (total and IgM), anti-HBs titres. Real-time quantitative PCR for Hepatitis B Virus DNA (HBV DNA) were performed for all HBsAg and or anti-HBc positive samples. ResultsOut of 2398 samples tested, 20 (0.83%) samples were positive for HBsAg, whereas 547 (22.81%) were positive for anti-HBc. Out of 547 samples, 16 (2.92%) were positive for HBV DNA with median level at 247.89 IU/mL (IQR: 126.05–666.67 IU/mL). Anti-HBs levels were positive in 35.83% of OBI cases. ROC curve analysis showed that combined HBsAg, anti-HBc and anti-HBs (>50 mIU/mL) screening can more efficiently detect HBV infection in blood donors than HBsAg alone. ConclusionsA combined HBsAg, anti-HBc and anti-HBs screening for donor samples could be an alternative achievable strategy to minimize the HBV transmission as well as financial burden. In resource limited setup, the proposed combined strategy could be helpful in minimizing the risk of OBI transmission.

HIV Pre-Exposure Prophylaxis, Blood Donor Deferral, Occult Infection, and Risk of HIV Transmission by Transfusion: A Fine Balance Between Evidence-Based Donor Selection Criteria and Transfusion Safety.

Pre- and postexposure prophylaxis for human immunodeficiency virus (HIV) are key to reducing the transmission of this virus. Furthermore, low-toxicity, long-acting formulations provide additional clinical benefits, in particular easier adherence to treatment and prevention. However, breakthrough HIV infections can occur despite the use of pre-exposure prophylaxis (PrEP), mainly due to suboptimal adherence or multi-drug resistant HIV strains. Albeit rare, PrEP breakthrough infections have also been reported in fully adherent patients. Should such breakthrough infection occur in an eligible blood donor, PrEP might suppress viremia and delay antibody seroconversion, thereby masking the infection and increasing the risk of transfusion transmission. This possibility has raised concerns in the blood transfusion community but remains little documented. Therefore, a literature search was performed to assess the state of knowledge on the risk of PrEP breakthrough infection, with a particular focus on the risk of HIV entering the blood supply. Evidently, PrEP breakthrough infections are rare, although the risk is not zero. Moreover, a fraction of individuals - including blood donors - do not disclose PrEP use according to various surveys and measurements of HIV PrEP analytes. Additionally, viremia and seroconversion may remain undetectable or close to the limit of detection for a long time after cessation of PrEP, particularly with long-acting antiretrovirals. Therefore, current recommendations to defer donors for at least 3 months after the last dose of oral PrEP or 2 years for long-acting PrEP appear justified, as they safeguard the blood supply and public trust toward the system. These recommendations help to safeguard blood safety and public trust in the blood supply.

Hepatitis E Virus in Finland: Epidemiology and Risk in Blood Donors and in the General Population.

Autochthonous hepatitis E (HEV) cases have been increasingly recognized and reported in Europe, caused predominantly by the zoonotic HEV genotype 3. The clinical picture is highly variable, from asymptomatic to acute severe or prolonged hepatitis in immunocompromised patients. The main route of transmission to humans in Europe is the ingestion of undercooked pork meat. Transfusion-transmitted HEV infections have also been reported. The aim of the study was to determine the HEV epidemiology and risk in the Finnish blood donor population. A total of 23,137 samples from Finnish blood donors were screened for HEV RNA from individual samples and 1012 samples for HEV antibodies. Additionally, laboratory-confirmed hepatitis E cases in 2016-2022 were extracted from national surveillance data. The HEV RNA prevalence data was used to estimate the risk of transfusion transmission of HEV in the Finnish blood transfusion setting. Four HEV RNA-positive were found, resulting in 1:5784 (0.02%) RNA prevalence. All HEV RNA-positive samples were IgM-negative, and genotyped samples represented genotype HEV 3c. HEV IgG seroprevalence was 7.4%. From the HEV RNA rate found in this study and data on blood component usage in Finland in 2020, the risk estimate for a severe transfusion-transmitted HEV infection is 1:1,377,000 components or one in every 6-7 years. In conclusion, the results indicate that the risk of transfusion-transmitted HEV (HEV TTI) in Finland is low. However, continuous follow-up of the HEV epidemiology in relation to the transfusion risk landscape in Finland is necessary, as well as promoting awareness in the medical community of the small risk for HEV TTI, especially for immunocompromised patients.

Demographic Factors Among HIV Confirmed Blood Donors from 2013 to 2021 in Shenzhen.

New HIV (Human immune deficiency virus) infections are continuously increasing in China and it remains a huge challenge to blood donation.As access to health services has affected by COVID-19 (Corona virus disease 2019) pandemic, a drop in new diagnoses (especially HIV) was observed worldwide. During 2013-2021, 735,247 specimens from unpaid blood donors collected by Shenzhen Blood Center underwent ELISA (Enzyme -linked immunosorbent assay) and NAT (Nucleic acid test). Samples with reactivity results were sent to the Shenzhen Center for Disease Control and Prevention for WB (Western blot). All data were statistically analyzed by the Chi-Square test. From 2013 to 2021, the prevalence of HIV among male blood donors was higher than in females (P < 0.01). During the COVID-19 pandemic, the prevalence of HIV among repeat blood donors decreased significantly compared to 2019 (P < 0.05), and the characteristics of blood donors changed in 2020 compared to 2019 and 2021. The high proportion of female blood donors would help prevent HIV from getting into the blood supply. The COVID-19 pandemic affected the demographics of blood donors as well as the prevalence of HIV among repeat blood donors. An increased number of repeat blood donors can help decrease the risk of HIV transfusion transmission during the epidemic.

Modeling the Risk of HIV Transfusion Transmission.

Blood donations are routinely screened for HIV to prevent an infectious unit from being released to the blood supply. Despite improvements to blood screening assays, donations from infected donors remain undetectable during the window period (WP), when the virus has not yet replicated above the lower limit of detection (LOD) of a screening assay. To aid in the quantitative risk assessments of WP donations, a dose-response model describing the probability of transfusion-transmission of HIV over a range of viral RNA copies was developed. An exponential model was chosen based on data fit and parsimony. A data set from a HIV challenge study using a nonhuman primate model and another data set from reported human blood transfusions associated with HIV infected donors were separately fit to the model to generate parameter estimates. A Bayesian framework using No-U-Turn Sampling (NUTS) and Monte Carlo simulations was performed to generate posterior distributions quantifying uncertainty in parameter estimation and model predictions. The parameters of the exponential model for both nonhuman primate and human data were estimated with a mean (95% credible intervals) of 2.70 × 10 -2 (7.74 × 10 -3 , 6.06 × 10 -2 ) and 7.56 × 10 -4 (3.68 × 10 -4 , 1.31 × 10 -3 ), respectively. The predicted ID 50 for the animal and human models was 26 (12, 90) and 918 (529, 1886) RNA copies transfused, respectively. This dose-response model can be used in a quantitative framework to estimate the probability of transfusion-transmission of HIV through WP donations. These models can be especially informative when assessing risk from blood components with low viral load.

Pathogen reduction of monkeypox virus in plasma and whole blood using riboflavin and UV light.

Monkeypox virus has recently emerged from endemic foci in Africa and, since October 20, 2022, more than 73,000 human infections have been reported by the CDC from over 100 countries that historically have not reported monkeypox cases. The detection of virus in skin lesions, blood, semen, and saliva of infected patients with monkeypox infections raises the potential for disease transmission via routes that have not been previously documented, including by blood and plasma transfusions. Methods for protecting the blood supply against the threats of newly emerging disease agents exist and include Pathogen Reduction Technologies (PRT) which utilize photochemical treatment processes to inactivate pathogens in blood while preserving the integrity of plasma and cellular components. Such methods have been employed broadly for over 15 years, but effectiveness of these methods under routine use conditions against monkeypox virus has not been reported. Monkeypox virus (strain USA_2003) was used to inoculate plasma and whole blood units that were then treated with riboflavin and UV light (Mirasol Pathogen Reduction Technology System, Terumo BCT, Lakewood, CO). The infectious titers of monkeypox virus in the samples before and after riboflavin + UV treatment were determined by plaque assay on Vero cells. The levels of spiked virus present in whole blood and plasma samples exceeded 103 infectious particles per dose, corresponding to greater than 105 DNA copies per mL. Treatment of whole blood and plasma units under standard operating procedures for the Mirasol PRT System resulted in complete inactivation of infectivity to the limits of detection. This is equivalent to a reduction of ≥ 2.86 +/- 0.73 log10 pfu/mL of infectivity in whole blood and ≥ 3.47 +/-0.19 log10 pfu/mL of infectivity in plasma under standard operating conditions for those products. Based on this data and corresponding studies on infectivity in patients with monkeypox infections, use of Mirasol PRT would be expected to significantly reduce the risk of transfusion transmission of monkeypox.

Risk of a blood donation contaminated with hepatitis E virus entering the blood supply before the implementation of universal RNA screening in France.

The risk of a blood donation contaminated with hepatitis E virus (HEV) entering the blood supply before introducing universal HEV-RNA screening in France was estimated to assess the benefit of such a measure. The results of selective HEV nucleic acid testing (HEV-NAT) performed in mini pool of six plasma donations between 2018 and 2020 were extrapolated to the whole blood donor (BD) population after adjustment on three variables: regional establishment, sex and age group. Among the 246,285 plasma donations collected from 172,635 BDs tested for HEV-RNA, 248 (10.1/10,000) were positive. The extrapolation to all BDs led to an estimated rate of 5.9/10,000 donations (95% confidence interval [CI]: 4.5-7.4) which would be positive to HEV-RNA and a prevalence of 9.9/10,000 BDs (95% CI: 7.5-12.3). This prevalence was 4.4 times higher in males than females (16.8/10,000 vs. 3.8/10,000, p < 10-4 ). The highest prevalence was observed in males in the 30-39 age group (20.5/10,000) and the lowest in females in the 50-70 age group (2.8/10,000). The risk of an HEV-RNA-positive donation entering the blood supply was estimated at 1 in 1682 donations. This risk does not translate directly to the risk of HEV transfusion transmission, which mainly depends on the total number of viral particles in the transfused blood component and the sensitivity of NAT.

West Nile virus transfusion-transmission risk in Australia associated with a seasonal outbreak in the United States.

West Nile virus (WNV) is a potentially transfusion-transmissible virus endemic in the US. The aim of this study was to estimate the monthly WNV transfusion transmission (TT) risk in Australia associated with donors returning from the US in 2018 and consider the implications for mitigation strategies. We used a probabilistic risk model to estimate the monthly WNV TT risks for each outbreak state/district in the US for the 2018 transmission season and the cumulative monthly risk for all US states/districts. The highest monthly cumulative transfusion risk in Australia occurred in August 2018 when 746 West Nile neuroinvasive disease cases were reported in the US and the estimated mean WNV TT risk in Australia was 1 in 1.0× 108 donations (95% confidence interval [CI]: 1.6× 108 -7.0× 107 ). The highest risk during August was associated with California, with a mean risk of 1 in 4.1× 108 donations (95% CI: 2.9× 108 -6.6× 108 ), representing 24% of the total risk in Australia. The cumulative TT risk in Australia for the other 11 months varied from 1 in 1.5× 108 donations (95% CI: 2.3× 108 -1.0× 108 ) in September to 1 in 3.9× 1010 donations (95% CI: 6.1× 1010 -2.7× 1010 ) in February. Our modeling indicates that the WNV TT risk in Australia associated with seasonal outbreaks in the US is extremely small and may not warrant donation restrictions for donors returning from the US.

Abstract 27 Limitations of Current Human Cell, Tissue, and Cellular-based Product Donor Eligibility Guidance: Analyzing the Impact on a Large Public Cord Blood Bank

IntroductionCord blood (CB) is considered a human cell, tissue, and cellular-based product (HCT/P) by the U.S. Food and Drug Administration (FDA) and is licensed through a Biological Licensing Application (BLA). Cord blood units (CBUs) require less precise donor tissue matching than other stem cell sources, which increases their availability for racial/ethnic minorities. However, a small percentage of banked CBUs are used for transplants. Updating FDA donor eligibility guidance may expand licensed CBU supply and cord blood bank (CBB) sustainability.ObjectiveThe objectives of this study were to analyze the impact of Zika virus (ZIKV) donor screening recommendations on the licensing status of banked CBUs and to propose updated policy recommendations.MethodsA retrospective analysis of Carolinas Cord Blood Bank (CCBB) data (from January 2016 to May 2022) was performed to describe CBU eligibility and shipment status. Qualitative comparisons of FDA guidance to reduce the risk of relevant communicable diseases were completed for blood versus HCT/P.Results CCBB: 8,877 banked CBUs from 2016-2022 (85.3% licensed; 14.7% unlicensed) (Table 1). 4,361 (49.1%) of CBUs were from Caucasian donors and 1,349 (15.2%) were from African American donors. 689 (52.7%) CBUs were unlicensed due to ZIKV risk. The number of CBUs with ZIKV risk banked annually has decreased significantly since 2020, with 174 ZIKV-risk CBUs in 2020 versus 63 in 2021. 26 unlicensed CBUs collected in 2016 or later have been infused versus 210 licensed CBUs. 7 unlicensed, infused CBUs had identified ZIKV risk. No ZIKV transmission was reported from these transplants. FDA Guidance: HCT/P ZIKV recommendations have not been updated since 2018 despite FDA removal of ZIKV from the relevant transfusion-transmitted infections in 2021. Recommendations for minimizing transfusion-transmission risk of human immunodeficiency virus (HIV) and variant Creutzfeldt-Jakob disease (vCJD) were updated in 2020 and 2022, respectively, to increase blood supply. New vCJD guidance eliminated geographic risk-related donor restrictions.Table 1.Characteristics of CBUs banked at CCBB January 2016 to May 2022CBU StatusNumber of Units (%)Banked8,877 (100%) Banked, licensed7,569 (85.3%) Banked, unlicensed1,308 (14.7%) Banked with ZIKV risk (travel-related donor deferral)689 (7.8%) Banked with Hepatitis B core antibody positive82 (<1.0%)Infused236/8,877 (2.7%) Infused, licensed210 (89.0 %) Infused, unlicensed26 (11.0%) Infused, Caucasian donor134 (56.8%) Infused, African American donor28 (11.9%) Infused, unlicensed with ZIKV risk7/26 (26.9%) Infused, unlicensed with Hepatitis B core antibody positive3/26 (11.5%)DiscussionGuidance for reducing disease transmission for blood and blood components have recently been updated to increase blood supply. The FDA must consider new data to revise the HCT/P donor screening recommendations. Adopting these changes will increase the number of HCT/P donors, the quantity of licensed CBUs, and potentially improve access to cellular therapies for a more diverse patient population.

Chikungunya virus seroprevalence in asymptomatic blood donors during an outbreak in the Federal District of Brazil.

Chikungunya virus (CHIKV) is a mosquito-borne alphavirus belonging to the Togaviridae family. The symptomatic infection is characterised by acute febrile disease which generally results in severe arthralgia and myalgia, however, most of the CHIKV infections remain asymptomatic. CHIKV RNA detection in asymptomatic volunteers may be responsible for the transfusion transmission of this infection, especially during outbreaks. There is no information for CHIKV seroprevalence among blood donors from the Federal District of Brazil. In early 2019, the Federal District of Brazil experienced a CHIKV outbreak, and this study evaluates the anti-CHIKV IgM and IgG presence in a well characterised cohort of blood donors from this region. Blood samples were collected from 450 volunteer blood donors during a CHIKV outbreak and tested for the presence of anti-CHIKV IgG and IgM antibodies using ELISA. The CHIKV seroprevalence was 0.89% (n=4/450) and anti-CHIKV IgM prevalence was 1.11% (n=5/450). The obtained results demonstrated that at least some of the blood donors have experienced CHIKV infection which can be related to a hypothetical risk of CHIKV transfusion transmission. More studies are necessary in order to examine the impact of CHIKV on blood transfusion.

Blood supply and transfusion safety during the COVID-19 pandemic

Introduction: The COVID-19 pandemic has put a strain on transfusion practices and safety. The Scientific Committees consider that the COVID-19 pandemic presents a potential risk of reducing and compromising the blood product supply and expressed considerable concern about transfusion safety. Method: In this concise review, we provide an overview of the implications of COVID-19 for blood safety and sufficiency during the initial phases of the pandemic. We searched the PubMed database, the websites of the World Health Organization, the European Centre for Disease Prevention and Control, the US Communicable Diseases Center. We used the keywords COVID-19, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the impact of COVID-19 on the blood supply, impact of COVID-19 on blood collection, COVID-19 and transfusion safety, the transmission of SARS-CoV-2 through blood transfusion, COVID-19 symptoms, asymptomatic blood donor, COVID-19 patients. Results: Data provided from blood transfusion centers and blood banks worldwide show that the COVID-19 pandemic has affected the activities of the blood supply system. It has impacted blood collections and caused a significant decrease in blood donors. The estimated asymptomatic infection rate was 15–46% of SARS-CoV-2 infections. The estimated incubation ranges are between 2 and 11 days, and almost all infections developed symptoms by day 14. The RNAemia phase of SARS-CoV-2 appears to be brief and low level, is typically associated with more severe disease, and is not demonstrated to be an infectious virus. It is detectable in only a tiny proportion of patients. Post-donation, post-transfusion information, and molecular testing of swab samples collected from asymptomatic donors at risk for COVID-19 provided data supporting the absence of transfusion transmission (TT) of COVID-19. The TT risk is currently theoretical. To prevent and minimize respiratory transmission of SARS-CoV-2 to donors and staff while donating blood, blood centers have had to activate their emergency plans and propose appropriate response measures. Conclusion: The COVID-19 pandemic has a significant impact on blood transfusion activities worldwide. The risk of transmission of COVID-19 through transfusion of blood collected from asymptomatic individuals is now only theoretical and likely minimal. Blood systems should adopt a national approach for coherence and coordination to ensure public confidence in blood safety and supply.

Dengue seropositivity among blood donors in a tertiary hospital in Kerala, Southern India.

Aim:The aim of this study was to screen blood donors in a tertiary hospital in Kerala for dengue during the period of peak dengue transmission.Materials and Methods:One hundred and seventy-eight continuous serum samples obtained from asymptomatic blood donors during the monsoon season were subjected to ELISA for Dengue NS1 antigen and dengue immunoglobulin M (IgM) antibodies.Results:Dengue IgM antibodies were positive in 20 (11.23%) donors and NS1 antigen was positive in 1 (0.56%) donor. The presence of these markers in asymptomatic blood donors showed that they may have had active or subclinical dengue infection at the time of donation or in the recent past. The presence of NS1 in particular raises the possibility that the donor may have been viremic at the time of donation.Conclusion:The findings of this study suggest the risk of transfusion transmission of dengue during the monsoon in Kerala and strengthen the case for dengue screening among blood donors during this period of high incidence.

Management of the process of blood and blood components supply in a pandemic situation in the Northeast region

The main challenge facing the team of the Regional Center for Transfusion Hematology Varna (RCTH Varna) during the pandemic COVID-19 stems from the need to quickly adapt the processes of blood donation and supply of blood and blood components to hospitals. Most similar to the current COVID-19 pandemic is the SARS-CoV epidemic in 2003, for which the WHO noted that no cases of SARS-CoV infection due to transfusion of blood and blood components, the risk of transfusion transmission of this new virus, although theoretical, cannot be ignored at this stage. The most significant impact that the pandemic has had on blood donation is the reduction of donors, the reduction of the demand for blood and blood components and the economic consequences for the blood centers. Aim: The aim of the present study is to present and assess the socio-economic nature of the impact of the pandemic on the activities of the RCTH Varna and on the basis of the obtained results to propose measures to overcome the crisis. Material and methods: For the period March-July 2020, an analysis was made of the data on the attendance of donors in the blood center, the blood and blood components provided to the medical establishments and the impact on the economic results of the COVID-19 center. Data were processed using SPSS, version 20.0, using comparative and correlation analyzes. Results: There was a significant decline in blood donation by 22.7% over the period compared to the same period in 2019, as well as a decline in demand for blood and blood components due to the suspension of planned surgical interventions in hospitals. All this leads to significant damage, most of which are organizational, technological and financial in nature for the blood center. Conclusion: The transition to the usual mode of operation will most likely depend on the severity and duration of the pandemic and the timely and adequate adaptation of the structures of RCTH Varna to the new reality and the organizational and qualification competencies of the employees.

Zika virus RNA detection in blood donors in São Paulo, Brazil

Introduction: The Zika Virus (ZIKV) is a single-stranded RNA genome virus, belonging to the family Flaviviridae, genus Flavivirus. Outbreaks around the world have demonstrated that the presence of asymptomatic viremic blood donors provides an increase in the risk of transfusion transmission (TT) and nucleic acid test (NAT) screening has been proposed to ensure the blood safety. This study implemented an “in-house” method to detect ZIKV RNA in blood sample donations.Methods: Primary plasma tubes are submitted to nucleic acid extraction on an automated platform. After extraction, the NAT set-up is performed in the robotic pipettor, in which an amplification mixture containing primers and probes for ZIKV and Polio vaccine virus (PV) are added in duplex as an internal control. The real-time polymerase chain reaction is then performed in a thermocycler, using the protocol established by the supplier.Results: From May 2016 to May 2018, 3,369 samples were collected from 3,221 blood donors (confidence coefficient 95%), of which 31 were considered false positive (0.92%), as they did not confirm initial reactivity when repeated in duplicates and 14 (0.42%) had their results invalid due to repeat failure in the internal control, 4 (0.12%), due to insufficient sample volume and 2 (0.05%), due to automatic pipettor failures. No Zika RNA reactive sample was identified.Conclusion: The test showed feasible to be incorporated into the blood screening routine. Our data do not indicate the need to screen for ZIKV RNA in São Paulo during the evaluated period. However, a generic NAT system covering a group of flaviviruses which are circulating in the region, such as DENV and YFV, among others, could be a useful tool.

Low risk of SARS-CoV-2 in blood transfusion.

BackgroundThe novel coronavirus disease (COVID-19) pandemic, caused by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), continues to remain a global challenge. There is emerging evidence of SARS-CoV-2 virus found in the blood of patients from China and some developed countries. However, there is inadequate data reported in Ghana and other parts of Africa, where blood transfusion service heavily relies on voluntary and replacement blood donors. This study aimed to investigate whether plasma of infected individuals could pose significant transfusion transmitted risk of COVID-19 in Ghanaian populations.MethodsThis cross-sectional retrospective study was conducted at the Kumasi Centre for Collaborative Research into Tropical Medicine (KCCR), KNUST, Ghana. Study subjects comprised contacts of COVID-19 individuals, those with classical symptoms of COVID-19 and individuals who had recovered based on the new Ghana discharge criteria. Whole blood, sputum or deep coughed saliva samples were collected and transported to KCCR for SARS-CoV-2 testing. Viral nucleic acid was extracted from sputum/nasopharyngeal samples using Da An Gene column based kit and from plasma using LBP nucleic acid extraction kit. Real-Time PCR was performed specifically targeting the ORF1ab and Nucleocapsid (N) genomic regions of the virus.ResultsA total of 97 individuals were recruited into the study, with more than half being males (58; 59.7%). The mean age of all subjects was 33 years (SD = 7.7) with minimum being 22 years and maximum 56 years. Majority (76; 78.4%) of all the subjects were asymptomatic, and among the few symptomatic subjects, cough (10; 10.3%) was the most predominant symptom. Of the 97 sputum samples tested, 79 (81.4%) were positive for SARS-CoV-2. We identified SARS-CoV-2 viral RNA in the plasma of 1 (1.03%) subject who had clinically recovered.ConclusionThis study reports the identification of SARS-CoV-2 viral RNA in a convalescent individual in Ghana. Due to the low prevalence observed and the marginal cycling thresholds associated, the risk of transfusion transmission of SARS-CoV-2 is negligible. Well-powered studies and advanced diagnostics to determine infectious viremia is recommended to further evaluate the potential risk of hematogenous transmission among recovered patients.

Filariasis and transfusion-associated risk: a literature review.

Filariae are parasitic worms that include the pathogens Loa loa, Onchocerca volvulus, Wuchereria bancrofti, Brugia spp. and Mansonella spp. which are endemic in parts of Africa, Asia, Asia-Pacific, South and Central America. Filariae have a wide clinical spectrum spanning asymptomatic infection to chronic debilitating disease including blindness and lymphedema. Despite successful eradication programmes, filarial infections remain an important -albeit neglected - source of morbidity. We sought to characterize the risk of transfusion transmission of microfilaria with a view to guide mitigation practices in both endemic and non-endemic countries. A scoping review of scientific publications as well as grey literature was carried out by a group of domain experts in microbiology, transfusion medicine and infectious diseases, representing the parasite subgroup of the International Society of Blood Transfusion. Cases of transfusion-transmitted filariasis are rare and confined to case reports of variable quality. Transfusion-associated adverse events related to microfilariae are confined to isolated reports of transfusion reactions. Serious outcomes have not been reported. No known strategies have been implemented, specifically, to mitigate transfusion-transmitted filariasis yet routine blood donor screening for other transfusion-transmissible infections (e.g. hepatitis B, malaria) may indirectly defer donors with microfilaremia in endemic areas. Rare examples of transfusion-transmitted filariasis, without serious clinical effect, suggest that filariasis poses low transfusion risk. Dedicated mitigation strategies against filarial transfusion transmission are not recommended. Given endemicity in low-resource regions, priority should be on the control of filariasis with public health measures.