Initial trends of individual donation nucleic acid testing in voluntary & replacement donors from a tertiary care centre in north India

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.

Blood Donation Screening of Transfusion-Transmissible Viral Infection Using Two Different Nucleic Acid Testing (NAT) Platforms: A Single Tertiary Care Oncology Centre Experience

Nucleic acid testing (NAT) is used to screen transfusiontransmittable infections (TTIs) in donated blood samples and provide an additional layer of blood safety. In this study, we describe our experience in screening viral TTIs using two formats of NAT: cobas® MPX2 polymerase chain reaction- based minipool NAT (PCR MP-NAT) and Procleix Utrio Plus transcription-mediated amplificationbased individual donor-NAT (TMA ID-NAT). Data routinely collected as a part of blood bank operations were retrospectively analysed over a period of 70 months for TTIs. Blood samples were initially screened for HIV, HBV, HCV, syphillis by chemiluminescence and malaria by Rapid card test. In addition to serological testing, all samples were further screened by TMA-based ID-NAT (ProcleixUltrio Plus Assay) during Jan 2015-Dec 2016, and by PCR-based MP-NAT (Cobas® TaqScreen MPX2) during Jan 2017-Oct 2020. RESULTS: A total of 48,151 donations were processed over 70 months, of which 16,212 donations were screened by ProcleixUtrio Plus TMA ID-NAT and 31,939 donations by cobas® MPX2 PCR MP-NAT. Replacement donors and male donors outnumbered voluntary donors and female donors respectively. The overall NAT yield rate of MP-NAT was 1:2281 compared to 1:3242 with ID-NAT, during the respective time period. ID-NAT detected 5 HBV infections missed by serology, whereas MP-NAT detected 13 HBV infections and 1 HCV infection missed by serology. The proportion of donations that were both seroreactive and NAT reactive was higher with MP-NAT (59.8%) compared to ID-NAT (34.6%). Cobas® MPX2MP-NAT had higher overall NAT yield rate compared to ProcleixUtrio Plus ID-NAT and confirmed a higher proportion of seroreactive donations. Due to the ease of operation, simple algorithm, cobas® MPX2 PCR based MP-NAT can be an effective solution for blood screening in India.