{"doi":"10.1186/s12879-021-05808-2","title":"Point-of-care p24 antigen detection for early infant diagnosis of HIV infection: cross-sectional and longitudinal studies in Zambia","abstract":"BACKGROUND: Early infant diagnosis of HIV infection is challenging in sub-Saharan Africa, particularly in rural areas, leading to delays in diagnosis and treatment. Use of a point-of-care test would overcome many challenges. This study evaluated the validity of a novel point-of-care p24 antigen detection test (LYNX) in rural and urban settings in southern Zambia. METHODS: Two studies were conducted: a cross-sectional study from 2014 to 2015 at Macha Hospital (LYNX Hospital study) and a longitudinal study from 2016 to 2018 at 12 health facilities in Southern Province, Zambia (NSEBA study). In both studies, children attending the facilities for early infant diagnosis were enrolled and a blood sample was collected for routine testing at the central lab and immediate on-site testing with the LYNX test. The performance of the LYNX test was measured in comparison to nucleic acid-based testing at the central lab. RESULTS: In the LYNX Hospital study, 210 tests were performed at a median age of 23.5 weeks (IQR: 8.9, 29.0). The sensitivity and specificity of the test were 70.0 and 100.0%, respectively. In the NSEBA study, 2608 tests were performed, including 1305 at birth and 1222 on children ≥4 weeks of age. For samples tested at birth, sensitivity was 13.6% (95% CI: 2.9, 34.9) and specificity was 99.6% (95% CI: 99.1, 99.9). While specificity was high for all ages, sensitivity increased with age and was higher for participants tested at ≥4 weeks of age (80.6%; 95% CI: 67.4, 93.7). Children with positive nucleic acid tests were more likely to be negative by the LYNX test if their mother received antiretroviral therapy during pregnancy (60.7% vs. 24.2%; p = 004). CONCLUSIONS: Considering the high specificity and moderate sensitivity that increased with age, the LYNX test could be of value for early infant diagnosis for infants ≥4 weeks of age, particularly in rural areas where centralized testing leads to long delays. Point-of-care tests with moderate sensitivity and high specificity that are affordable, easy-to-use, and easily implemented and maintained should be developed to expand access to testing and deliver same-day results to infants in areas where it is not feasible to implement nucleic acid-based point-of-care assays.","journal":"BMC Infectious Diseases","year":2021,"id":199706,"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":8,"citer_count":0,"citers_with_citation_signal":0,"citers_with_endowment":0,"datacite_reuse_total":0,"is_dataset":false,"is_dataset_confidence":0.9449,"is_data_producer":false,"deposit_databanks":null,"is_oa":true,"file_count":0,"downloads":0,"has_version_chain":false,"published_date":"2021-01-01","fair_score":null,"fair_percentile":null,"algorithm_id":"datarank_citation_only_1hop_v6","ranking_scope":"data_only","authors":[{"id":371977,"name":"Jane N. Mutanga","orcid":"0000-0002-1951-3565","position":1,"is_corresponding":false},{"id":373025,"name":"Nkumbula Moyo","orcid":null,"position":2,"is_corresponding":false},{"id":776264,"name":"Abhishek Agarwal","orcid":"0000-0002-5881-7182","position":3,"is_corresponding":false},{"id":371978,"name":"Jessica L. Schue","orcid":"0000-0002-5188-5692","position":4,"is_corresponding":false},{"id":371979,"name":"Mutinta Hamahuwa","orcid":"0009-0006-6301-5148","position":5,"is_corresponding":false},{"id":579303,"name":"Kara Palamountain","orcid":"0000-0002-8055-9706","position":6,"is_corresponding":false},{"id":420872,"name":"Mark Fisher","orcid":"0000-0001-9802-8826","position":7,"is_corresponding":false},{"id":776762,"name":"Robert Elghanian","orcid":null,"position":8,"is_corresponding":false},{"id":269844,"name":"Philip E. Thuma","orcid":"0000-0002-1508-4409","position":9,"is_corresponding":false},{"id":270628,"name":"William J. Moss","orcid":"0000-0001-6579-3513","position":10,"is_corresponding":false},{"id":371976,"name":"Catherine G. Sutcliffe","orcid":"0000-0001-8512-8326","position":0,"is_corresponding":true}],"reference_count":19,"raw_metadata":null,"created_at":"2026-07-18T23:50:40.558460Z","pmid":"33499820","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":[]}