Breakthrough infection by hepatitis B virus in a vaccinated blood donor: An emerging threat for transfusion safety in low-endemic countries?

We present the case of a breakthrough infection by hepatitis B virus (HBV), intending to warn about the challenge that HBV represents for transfusion safety. Virological markers for HBV infection were assayed during a blood donor screening by detection of HBsAg, anti-HBc, and viral nucleic acid (HBV DNA) by a nucleic acid test (NAT). Additionally, samples were analyzed for detection of immunoglobulin M anti-HBc, HBeAg, anti-HBe, and anti-HBs. A first-time donor repeatedly tested positive for HBV DNA by NAT and nonreactive for HBV-serological markers of infection. He stated having completed the anti-HBV vaccination schedule; thus, study of anti-Hbs resulted in reactive at protective level (18 mIU/mL). The donor denied clinical symptoms of hepatitis and remained healthy during the follow-up period. 95 days postdonation, NAT was negative, seroconversion of anti-HBc ab was detected, and a significant increase in anti-HBs concentration was measured (>1000 mIU/mL). This is the first case of HBV-breakthrough infection reported in Argentina and to our knowledge, this potential threat to transfusion safety is novel in an HBV low-endemic region with high coverage of HBV vaccination. The occurrence of breakthrough infections challenges the current protocols for the identification of HBV-infected subjects, could be a source of silent HBV transmission.

NAT yield in blood donors: An observational study

Introduction

Individual donation nucleic acid testing (ID-NAT) is considered as highly sensitive technology for viral transfusion-transmissible infections (TTIs) in blood donors. The present study was aimed to analyze the results of ID-NAT with special reference to different types of donors, their age, gender, blood group ranges in a tertiary care center in north India.

Methodology

The present study was done from 24th June 2019 to 31st December 2021 in Blood Center, Department of Immunohematology and Blood Transfusion, SMS Hospital, Jaipur. A total of 18313 apparently healthy adult donors were included in present study.

Result

In 2019 Combined NAT yield was 1 in 754, in 2020 it was 1 in 2368 and in 2021 it was 1 in 741. With Total NAT yield was 1 in 1017 (0.09 %) over a period of study. NAT yield in HBV is 1 in 1077, in HCV 1 in 18313 and no NAT Yield in HIV.

Conclusion

NAT testing for hepatitis B provides additional safety because ELISA does not pick up occult hepatitis. The non-seroconverting or delayed seroconverting disease is missed by ELISA alone and can be picked up by NAT.

Re-examine the transfusion transmitted risk of SARS-CoV-2 virus during a major COVID-19 outbreak in 2022

INTRODUCTION

Although no case of COVID-19 transmission through transfusion has been reported, blood transfusion service (BTS) continues to implement pre-donation and post-donation measures to minimise the risk. In year 2022, when local healthcare system was badly impacted by a major outbreak, it opened an opportunity to re-examine the viraemia risk in these asymptomatic donors.

MATERIALS AND METHODS

Records were retrieved from blood donors who reported COVID-19 after donation and follow-up was also made for recipients who received their blood. Blood samples at donation were tested for SARS-CoV-2 viraemia by single-tube nested real-time RT-PCR assay designed to detect most SARS-CoV-2 variants including the prevailing delta and omicron variants.

RESULTS

From 1 January to 15 August 2022, the city with 7.4 M inhabitants recorded 1 187 844 COVID-19 positive cases and 125 936 successful blood donations were received. 781 donors reported to the BTS after donation with 701 being COVID-19 related (including close contact and symptoms respiratory tract infection). 525 COVID-19 were positive at the time of call back or follow-up. Of the 701 donations, they were processed into 1480 components with 1073 discarded upon donors' call back. For remaining 407 components, no recipient was found to have adverse event or COVID-19 positive. 510 samples from the above 525 COVID-19 positive donors were available and all tested negative for SARS-CoV-2 RNA.

DISCUSSION

With the negative SARS-CoV-2 RNA in blood donation samples and follow up data in transfusion recipients, the risk of transfusion transmitted COVID-19 appears negligible. However, current measures remains important in securing blood safety with ongoing surveillance of their effectiveness.

Low rates of transfusion-transmitted infection screening in chronically transfused adults with sickle cell disease

BACKGROUND

Adults with sickle cell disease (SCD) on chronic transfusion therapy are exposed to a large volume of blood products, thus increasing their risk of transfusion-associated human immunodeficiency virus (HIV), hepatitis C (HCV), and hepatitis B (HBV).

METHODS

We performed a systematic chart review of chronically transfused SCD subjects at the Johns Hopkins Sickle Cell Center for Adults between October 2014 and September 2019 to determine our Center's adherence to the 2014 National Heart, Lung and Blood Institute (NHLBI) SCD guidelines for annual screening for Transfusion Transmitted infections (TTI) and assessed HBV immunity and HBV vaccination rates.

RESULTS

The study included 85 subjects with a median age of 34 years (23-63); 52% were female. No subject received annual screening; 68 subjects (80%) were screened for HIV, 60 subjects (71%) for HCV and 53 subjects (62%) for HBV infections at least once in the study period. Of those screened, one patient was newly diagnosed with HCV infection, and none with HIV or HBV infection. Among 31 subjects tested for anti-Hepatitis B surface antibody, 16 subjects (52%) tested negative. Nineteen (20%) subjects had HBV vaccination documented.

CONCLUSIONS

Low adherence to the NHLBI TTI screening guidelines, especially for HBV, highlights the resource intensiveness of this patient population. The low rates of anti-Hepatitis B surface antibody positivity highlight the need to confirm vaccination, provide boosters as indicated, and investigate the adults with SCD's immune response to HBV vaccination.

Frequency of Hepatitis B, C and HIV Infections among Transfusion-Dependent Beta Thalassemia Patients in Dhaka

Transfusion transmitted infections have remained a major deterrent to public health, particularly among the patients with transfusion-dependent Beta thalassemia in developing countries. Although proper donor selection through adoption of WHO-advised infection panel has lowered the rate of infections, the multi-transfused patients are not free of risk. In this study, we screened 148 transfusion-dependent Beta thalassemia patients to determine the frequency of Hepatitis C Virus (HCV), Hepatitis B Virus (HBV) and Human Immunodeficiency Virus (HIV) using the ELISA method. Among them, infected cases with HCV, HBV and HIV were 13.51%, 3.37% and 0%, respectively. Moreover, 2% of the patients were found to be co-infected with both HBV and HCV. The percentage of infections in the patients with frequent transfusion interval (≤30 days) was significantly higher (p < 0.0005) than that in the patients with less frequent transfusion intervals (>30 days). Immunochromatography (ICT)-based rapid test kits are usually used to screen and confirm these infections in the blood of the patients. However, ICT-based tests are not sensitive enough to detect the infections. So, a combination of both Nucleic Acid testing (NAT) and serological testing are suggested to significantly reduce the risk of viral infections during blood transfusion.

Prevalence of Hepatitis B Virus and Hepatitis C Virus Among Blood Donors in Nekemte Blood Bank, Western Oromia, Ethiopia: Retrospective 5 Years Study

Background

Hepatitis B virus and hepatitis C virus are the greatest threats to blood safety for the recipient. This study aimed to determine the seroprevalence and trends of HBV and HCV infections among blood donors over a period of 5 years at Nekemte blood bank, Ethiopia.

Methods

A retrospective study was conducted from January 2015 to December 2019 at Nekemte blood bank. The recorded blood donors' history and laboratory tests were reviewed by data collectors analyzed with Statistical Package for the Social Sciences version 20 software. A p-value of less than 0.005 was considered statistically significant.

Results

A total of 17,810 consecutive blood donors were screened between January 2015 and December 2019. The seroprevalence of HBV and HCV was 3.06% and 0.64%, respectively. The prevalence of HBV was significantly associated with male (AOR: 2.51; 95% CI: 1.17, 2.91), unmarried (AOR: 2.81; 95% CI: 1.79, 2.51) and rural (AOR: 2.11; 95% CI: 1.17, 3.05) blood donors. The prevalence of HCV was significantly associated with blood donor those were male (AOR: 3.01; 95% CI: 1.17, 3.91), within 45-65 years of age (AOR: 3.56: 95% CI: 1.14, 3.99) and unmarried (AOR: 3.14; 95% CI: 1.65, 3.96).

Conclusion

The current study shows the prevalence of hepatitis B virus was higher among study participants. However, the prevalence of HCV was low compared to the study conducted in other countries in Africa, a substantial percentage of the blood donors harbor HCV infections. Therefore, it is recommended to increase awareness of people (particularly on unmarried, male and rural resident) on modes of transmission and prevention of infection could help in reducing the burden of both HBV and HCV.

Human T-cell lymphotropic virus type I and II seroprevalence among volunteer blood donors in Thailand

Human T-cell lymphotrophic virus type I and II (HTLV-I/II) are closely related but distinct retroviruses that can infect humans. Both the viruses can be transmitted via transfusion of contaminated blood components. HTLV pre-transfusion screening is not mandatory in Thailand until now. Current epidemiological data for HTLV prevalence is still lacking since the past surveys were done more than a decade ago. The main objective of this study was to determine the seroprevalence of HTLV-I/II among voluntary blood donors in Thailand. 11,057 volunteer blood donors were screened for HTLV-I/II antibodies using the ARCHITECT rHTLV-I/II chemiluminescent immunoassay (CLIA). Initial-reactive (IR)  samples were subjected to repeat duplicate testing and were also sent for confirmatory testing at Korean Red Cross Society (KRC), Seoul or National Serology Reference Laboratories (NRL), Australia using alternate HTLV serological assays and immunoblot and/or specific nucleic acid testing respectively. Out of 11,057 plasma samples, 10,080 were low-risk seronegative donors and 977 were first-time/high-risk donors. Twenty of 24 IR samples were repeatedly reactive (RR) in low-risk seronegative donors group. On confirmatory testing of these 24 IR by immunoblot, 13 indeterminate and 11 negative results were observed. One out of 977 samples from first-time/high-risk donors was RR for anti-HTLV-I/II antibodies. This sample was co-reactive for HBsAg, but negative for HTLV by EIA or in-house HTLV-I qPCR. The ARCHITECT rHTLV-I/II assay exhibited a specificity of 99.93% in low-risk donors and 99.90% among high-risk donors. This study concluded that HTLV-I/II prevalence is low among blood donors in Thailand. But periodic surveillance should be continually conducted to ensure high blood safety standards in the country.

Impact of grey zone sample testing by enzyme-linked immunosorbent assay in enhancing blood safety: Experience at a tertiary care hospital in North India

BACKGROUND

Enzyme-linked immunosorbent assay (ELISA) used for screening blood donors for transfusion transmitted infections (TTIs) can sometimes fail to detect blood donors who are recently infected or possessing the low strength of pathogen. Estimation of a grey zone in ELISA testing and repeat testing of grey zone samples can further help in reducing the risks of TTI in countries where nucleic acid amplification testing for TTIs is not feasible.

MATERIALS AND METHODS

Grey zone samples with optical density (OD) lying between cut-off OD and 10% below the cut-off OD (cut-off OD × 0.9) were identified during routine ELISA testing. On performing repeat ELISA testing on grey zone samples in duplicate, the samples showing both OD value below grey zone were marked nonreactive, and samples showing one or both OD value in the grey zone were marked indeterminate. The samples on repeat testing showing one or both OD above cut-off value were marked positive.

RESULTS

About 119 samples (77 for hepatitis B virus [HBV], 23 for human immunodeficiency virus [HIV], and 19 for hepatitis C virus [HCV]) were found to be in grey zone. On repeat testing of these samples in duplicate, 70 (58.8%) samples (45 for HBV, 12 for HIV, and 13 for HCV) were found to be reactive. Six (5%) samples (four for HBV, one for HIV, and one for HCV) were found to be indeterminate.

CONCLUSION

Seventy donors initially screened negative, were found out to be potentially infectious on repeat grey zone testing. Thus, estimation of grey zone samples with repeat testing can further enhance the safety of blood transfusion.