Introduction: Misclassification errors have been reported in rapid diagnostic HIV tests (RDTs) in sub‐Saharan African countries. These errors can lead to missed opportunities for prevention‐of‐mother‐to‐child‐transmission (PMTCT), early infant diagnosis and adult HIV‐prevention, unnecessary lifelong antiretroviral treatment (ART) and wasted resources. Few national estimates or systematic quantifications of sources of errors have been produced. We conducted a comprehensive assessment of possible sources of misclassification errors in routine HIV testing in Zimbabwe.Methods: RDT‐based HIV test results were extracted from routine PMTCT programme records at 62 sites during national antenatal HIV surveillance in 2017. Positive‐ (PPA) and negative‐percent agreement (NPA) for HIV RDT results and the false‐HIV‐positivity rate for people with previous HIV‐positive results (“known‐positives”) were calculated using results from external quality assurance testing done for HIV surveillance purposes. Data on indicators of quality management systems, RDT kit performance under local climatic conditions and user/clerical errors were collected using HIV surveillance forms, data‐loggers and a Smartphone camera application (7 sites). Proportions of cases with errors were compared for tests done in the presence/absence of potential sources of errors.Results: NPA was 99.9% for both pregnant women (N = 17224) and male partners (N = 2173). PPA was 90.0% (N = 1187) and 93.4% (N = 136) for women and men respectively. 3.5% (N = 1921) of known‐positive individuals on ART were HIV negative. Humidity and temperature exceeding manufacturers’ recommendations, particularly in storerooms (88.6% and 97.3% respectively), and premature readings of RDT output (56.0%) were common. False‐HIV‐negative cases, including interpretation errors, occurred despite staff training and good algorithm compliance, and were not reduced by existing external or internal quality assurance procedures. PPA was lower when testing room humidity exceeded 60% (88.0% vs. 93.3%; p = 0.007).Conclusions: False‐HIV‐negative results were still common in Zimbabwe in 2017 and could be reduced with HIV testing algorithms that use RDTs with higher sensitivity under real‐world conditions and greater practicality under busy clinic conditions, and by strengthening proficiency testing procedures in external quality assurance systems. New false‐HIV‐positive RDT results were infrequent but earlier errors in testing may have resulted in large numbers of uninfected individuals being on ART.

The HIV-1 epidemic continues to challenge global public health, especially in sub-Saharan Africa. The rise in drug-resistant viruses, particularly pan-resistant strains, threatens treatment effectiveness, hindering progress toward UNAIDS viral suppression goals. This is critical in low-to-middle income countries (LMICs) like Zimbabwe, where treatment options and access to drug resistance testing are limited. This cross-sectional study analyzed 102 genotypes from patients with HIV-1 RNA ≥ 1000 copies/mL after at least 6 months on a dolutegravir (DTG)-based ART. HIV-1 genotyping and drug resistance interpretation were performed using the Stanford HIV Drug Resistance Database. Overall, 62% of genotypes harbored at least one drug resistance mutation, with 27% showing integrase strand transfer inhibitor (INSTI)-associated mutations. High-level resistance to DTG and cabotegravir was found in 14% and 23% of integrase sequences, respectively, primarily driven by G118R and E138K/T mutations. Pan-resistance was observed in 18% of complete genotypes, with one case of four class resistance. These results highlight the emergence of INSTI resistance in LMICs. The study underscores the urgent need for enhanced HIV drug resistance testing, continuous surveillance, and strategic optimization of ART regimens in resource-constrained settings to ensure effective HIV management.

Background: Virological failure (VF) on protease inhibitor (PI)-based second-line antiretroviral therapy (ART) remains an important driver of HIV drug resistance (HIVDR) in sub-Saharan Africa. Despite widespread adoption of dolutegravir (DTG)-based first-line ART, many people living with HIV (PLWH) remain on PI-based second-line regimens. Data on major PI drug resistance mutations (DRMs) in Zimbabwe remain limited. Methods: We conducted a retrospective cross-sectional study of archived plasma specimens from PLWH with VF (viral load (VL) ≥ 1,000 copies/mL) receiving PI-based second-line ART in Zimbabwe between January 2021 and June 2025. HIV-1 protease and reverse transcriptase regions were Sanger-sequenced, and resistance was interpreted using the Stanford HIV Drug Resistance Database. Factors associated with major PI DRMs were evaluated using multivariable logistic regression. Results: Among 297 participants, 153 (51.5%, 95% confidence interval [CI] 45.8–57.2%) harboured major PI DRMs. The most frequent mutations were M46I (22.6%), V82A (19.2%), and I54V (17.2%). NRTI- and NNRTI-associated DRMs were present in 70.4% and 79.5% of participants, respectively, while 47.8% exhibited triple-class resistance. Predicted susceptibility to darunavir/ritonavir remained high (78.8%), despite resistance to atazanavir/ritonavir (45.5%) and lopinavir/ritonavir (50.8%). In multivariable analysis, increasing age (adjusted odds ratio [aOR] 1.04, P < 0.001), higher VL (aOR 1.55, P = 0.011) and male sex (aOR 1.59, P = 0.044) were independently associated with major PI DRMs. Conclusions: Major PI DRMs and multiclass HIVDR were common among PLWH with VF on PI-based second-line ART. Routine VL monitoring and early resistance testing are needed to detect and guide second-line ART failure in Zimbabwe.