Concordance between point-of-care nucleic acid tests and conventional DNA-PCR for

Early Infant Diagnosis in HIV-exposed Mozambican infants on enhanced postnatal

antiretroviral prophylaxis

Cacildo Magul (1#), Camille Rich (2#), Hernane Gemusse (1), Abrás Munguambe (3), Raeven Grant (2); Dadirayi Musaka (3); Chishamiso Mudenyanga (3), Osvaldo Loquiha(3,4), Nália Ismael (1*), W. Chris Buck (2*)

1 Instituto Nacional de Saúde, Maputo, Mozambique

2 University of California Los Angeles David Geffen School of Medicine, Los Angeles, USA

3 Clinton Health Access Initiative, Maputo, Mozambique

4 Universidade Eduardo Mondlane, Maputo, Mozambique

# Co-first authors

* Co-last authors

Area of Concentration (Petal): Global Health

Specialty (if any): Pediatrics

Keywords: Early Infant Diagnosis, point-of-care, postnatal prophylaxis

Background: Mozambique guidelines recommend that all HIV-exposed infants (HEI) receive

enhanced postnatal prophylaxis (ePNP) for prevention of vertical transmission (VT) with

Zidovudine and Nevirapine for 6 and 12 weeks, respectively. Birth testing for HEI has not yet

been implemented--the first Early Infant Diagnosis (EID) test is performed at one month of age.

EID has traditionally been DNA-PCR testing performed on conventional platforms in centralized

laboratories using dried blood spot (DBS) samples, but point-of-care nucleic acid testing (POC-

NAT), which is based on RNA-PCR measurement, is also being used at high-volume EID

clinics. There is a need for data on the performance of POC-NAT platforms in HEI receiving

ePNP given theoretical concerns that viral suppression from ePNP could cause false negative

results in infants born with HIV or with early acquisition through breastfeeding.

Objective: To compare results from POC-NAT and DNA PCR EID tests in HEI who

received ePNP.

Methods: This is an ongoing prospective diagnostic study recruiting a target of 871 participants

1-4 months of age at five sites in Maputo from October 2024-May 2025. Participants have an

Abbott m-PIMATM POC-NAT performed, with a second confirmatory test if positive, and a DBS

collected for DNA-PCR and RNA-PCR/viral load (for positives) on the COBAS®6800 platform.

Results: Interim analysis was performed in April 2025 for 587 participants with POC-NAT and

DNA-PCR results available, with 337, 74, 86, and 90 participants of 1-, 2-, 3-, and 4-months of

age included. There were 3 (<0.01%) participants with positive DNA-PCR and POC-NAT

results, 1 participant with discordant POC-NAT results and a negative DNA-PCR, and no other

participants with discordant POC-NAT and DNA-PCR results. The viral load of participants with

positive DNA-PCR tests ranged from 19,550 to >10,000,000 copies/mL.

Conclusions: Preliminary results demonstrate very low early VT with no false-negative POC-

NAT results in HEI receiving ePNP.