{"doi":"10.1002/jia2.26235","title":"Factors associated with vertical transmission of HIV in the Western Cape, South Africa: a retrospective cohort analysis","abstract":"INTRODUCTION: Monitoring mother-infant pairs with HIV exposure is needed to assess the effectiveness of vertical transmission (VT) prevention programmes and progress towards VT elimination. METHODS: We used routinely collected data on infants with HIV exposure, born May 2018-April 2021 in the Western Cape, South Africa, with follow-up through mid-2022. We assessed the proportion of infants diagnosed with HIV at birth (≤7 days), 10 weeks (>1 to 14 weeks) and >14 weeks as proxies for intrauterine, intrapartum/early breastfeeding and late breastfeeding transmission, respectively. We used mixed-effects Poisson regression to assess factors associated with VT in mothers known with HIV by delivery. RESULTS: We included 50,461 infants born to mothers known with HIV by delivery. HIV was diagnosed in 894 (1.8%) infants. Among mothers, 51% started antiretroviral treatment (ART) before and 27% during pregnancy; 17% restarted during pregnancy after ≥6 months interruption; and 6% had no recorded ART during pregnancy. Most pregnancy ART regimens included non-nucleoside reverse transcriptase inhibitors (83%). Of mothers with available results (90% with viral load [VL]; 70% with CD4), VL nearest delivery was <100 copies/ml in 78% and CD4 count ≥350 cells/μl in 62%. HIV-PCR results were available for 86%, 67% and 48% of eligible infants at birth, 10 weeks and >14 weeks. Among these infants, 0.9%, 0.4% and 1.5% were diagnosed positive at birth, 10 weeks and >14 weeks, respectively. Among infants diagnosed with HIV, 43%, 16% and 41% were diagnosed at these respective time periods. Among mothers with VL<100, 100-999, 1000-99,000 and ≥100,000 copies/ml nearest delivery, infant HIV diagnosis incidence was 0.4%, 2.3%, 6.6% and 18.4%, respectively. Increased VT was strongly associated with recent elevated maternal VL with a seven-fold increased rate with even modestly elevated VL (100-999 vs. <100 copies/ml). VT was also associated with unknown/low maternal CD4, maternal age <20 years, no antenatal ART, later maternal ART start/restart in pregnancy and ART gaps. CONCLUSIONS: Despite high maternal ART coverage and routine postnatal prophylaxis, ongoing VT remains a concern. Timing of infant HIV diagnoses suggests intrapartum and/or breastfeeding transmission in nearly 60%. Interventions to ensure retention on ART and sustained maternal viral suppression are needed to reduce VT.","journal":"Journal of the International AIDS Society","year":2024,"id":433823,"datarank":0.0,"base_score":0.0,"endowment":0.0,"self_citation_contribution":0.0,"citation_network_contribution":0.0,"self_endowment_contribution":0.0,"citer_contribution":0.0,"corpus_percentile":null,"corpus_rank":null,"citation_count":13,"citer_count":0,"citers_with_citation_signal":0,"citers_with_endowment":0,"datacite_reuse_total":0,"is_dataset":false,"is_dataset_confidence":0.8962,"is_data_producer":false,"deposit_databanks":null,"is_oa":true,"file_count":0,"downloads":0,"has_version_chain":false,"published_date":"2024-01-01","fair_score":null,"fair_percentile":null,"algorithm_id":"datarank_citation_only_1hop_v6","ranking_scope":"data_only","authors":[{"id":486277,"name":"Emma Kalk","orcid":"0000-0001-7706-6866","position":1,"is_corresponding":false},{"id":110175,"name":"Alexa Heekes","orcid":"0000-0003-2430-5194","position":2,"is_corresponding":false},{"id":110179,"name":"Florence Phelanyane","orcid":"0000-0003-3586-3829","position":3,"is_corresponding":false},{"id":486275,"name":"Nisha Jacob","orcid":"0000-0002-7028-5772","position":4,"is_corresponding":false},{"id":110156,"name":"Andrew Boulle","orcid":"0000-0002-7713-8062","position":5,"is_corresponding":false},{"id":917429,"name":"Ushma Mehta","orcid":"0000-0002-0032-3171","position":6,"is_corresponding":false},{"id":752001,"name":"Reshma Kassanjee","orcid":"0000-0002-1200-8726","position":7,"is_corresponding":false},{"id":530900,"name":"Gayathri Sridhar","orcid":null,"position":8,"is_corresponding":false},{"id":1240022,"name":"Leigh Ragone","orcid":null,"position":9,"is_corresponding":false},{"id":364607,"name":"Vani Vannappagari","orcid":"0000-0002-0157-9689","position":10,"is_corresponding":false},{"id":110157,"name":"Mary‐Ann Davies","orcid":"0000-0001-8496-6475","position":11,"is_corresponding":false},{"id":917428,"name":"Kim Anderson","orcid":"0000-0002-2453-6219","position":0,"is_corresponding":true}],"reference_count":43,"raw_metadata":null,"created_at":"2026-07-19T01:59:49.434790Z","pmid":"38528395","pmcid":null,"fwci":null,"citation_percentile":null,"influential_citations":0,"oa_status":null,"license":null,"views":0,"total_file_size_bytes":0,"version_count":0,"fair_f":null,"fair_a":null,"fair_i":null,"fair_r":null,"fair_zscore":null,"fair_rationale":null,"fair_model":null,"fair_agent_version":null,"fair_fulltext_source":null,"fair_has_llm":null,"fair_computed_at":null,"clinical_trials":[],"software_tools":[],"db_accessions":[],"linked_datasets":[],"topics":[]}