# High false hepatitis C antibody positivity rate in a regionally-inclusive population of non-renumerated blood donors in Uganda

## TL;DR

A study in Uganda found that many blood donors testing positive for hepatitis C antibodies were false positives, suggesting the need for more accurate testing methods.

## Contribution

The study reveals a high false positivity rate of the CMIA platform for anti-HCV testing in Uganda, advocating for improved diagnostic protocols.

## Key findings

- 92.2% of CMIA-positive samples were false positives when tested with ELISA.
- Only 8.0% of samples showed active HCV infection via NAT.
- Three samples indicated resolved infection based on ELISA and NAT results.

## Abstract

Successful elimination of hepatitis as a public health threat by 2030 will partly rely on the availability and accessibility of affordable accurate disease testing platforms. In the past, testing of hepatitis C virus (HCV) in low resource settings of sub-Saharan Africa (SSA) has relied on anti-HCV testing using rapid diagnostic tests, chemiluminescent microparticle immunoassay (CMIA) and Enzyme-linked Immunosorbent Assays (ELISA) whose diagnostic accuracy has been sub-optimal. We determined the false positivity rate of a CMIA platform that is routinely used to screen donor blood for anti-HCV in Uganda.

1,216 CMIA-screened anti-HCV-positive blood donor samples at four regional Ugandan blood banks, were subjected to a third generation ELISA and subsequently to nucleic acid testing (NAT).

Of the above 1,216 samples, 1,122 (92.2%) were negative on ELISA and thus deemed false positives. Active infection (NAT positive) was detected in 98 (8.0%). Presumed resolved infection was recorded among 3 (3.2%) of participants that remained positive on the ELISA platform but negative on NAT.

The Architect CMIA assay exhibited very low specificity for anti-HCV testing. In this context, this finding may suggest need to employ testing protocols that include NAT or a combination of tests with higher validity.