{"doi":"10.1016/j.jinf.2025.106550","title":"Bordetella pertussis infection and antibody dynamics in household cohorts in two South African communities, 2016 – 2018: findings from the PHIRST study","abstract":"INTRODUCTION AND METHODS: In a cohort study, enrolling new households annually during 2016-2018, we estimated the B. pertussis attack rate using serology and PCR, identified factors associated with seroconversion, and described antibody changes over time. Nasopharyngeal swabs were collected biweekly for 6-10 months annually, with cases defined as individuals testing PCR-positive at least once. Seroconversion was defined as a ≥4-fold increase in anti-pertussis toxin IgG concentration between consecutive blood draws. Logistic regression was used to identify factors associated with seroconversion among PCR-positive individuals. RESULTS: Among 1509 participants, the serology attack rate was 5.8% (87/1509), 6.2% (94/1509) by PCR, and 9.6% (145/1509) combining both methods. Among PCR-positive cases, 38.3% (36/94) seroconverted, with a mean time to seroconversion of 2.9 months (range: 3 weeks-5.9 months). Younger participants (5-18 years) (adjusted odds ratio (aOR) 6.8, 95% confidence interval (CI) 1.3-35.1) and those with episode durations of ≥7 days (aOR 13.3, 95% CI 3.4-51.1) were more likely to seroconvert. Among the seroconverted, 75.0% (27/36) maintained antibody concentrations >40 IU/ml for at least 12 months post-infection. DISCUSSION: Almost 10% of participants had B. pertussis infection during follow-up. Less than half of individuals with PCR-confirmed infection seroconverted but maintained elevated antibodies for at least one-year post-infection.","journal":"Journal of Infection","year":2025,"id":570203,"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":0,"citer_count":0,"citers_with_citation_signal":0,"citers_with_endowment":0,"datacite_reuse_total":0,"is_dataset":false,"is_dataset_confidence":0.8579,"is_data_producer":false,"deposit_databanks":null,"is_oa":true,"file_count":0,"downloads":0,"has_version_chain":false,"published_date":"2025-01-01","fair_score":null,"fair_percentile":null,"algorithm_id":"datarank_citation_only_1hop_v6","ranking_scope":"data_only","authors":[{"id":629771,"name":"Jackie Kleynhans","orcid":"0000-0001-7081-6273","position":1,"is_corresponding":false},{"id":1475880,"name":"Lillian Makhathini","orcid":null,"position":2,"is_corresponding":false},{"id":680425,"name":"Mignon du Plessis","orcid":"0000-0001-9186-0679","position":3,"is_corresponding":false},{"id":227083,"name":"Stefano Tempia","orcid":"0000-0003-4395-347X","position":4,"is_corresponding":false},{"id":619231,"name":"Meredith McMorrow","orcid":"0000-0001-6363-4033","position":5,"is_corresponding":false},{"id":629772,"name":"Jocelyn Moyes","orcid":"0000-0001-8040-1717","position":6,"is_corresponding":false},{"id":631212,"name":"Amelia Buys","orcid":null,"position":7,"is_corresponding":false},{"id":631213,"name":"Lorens Maake","orcid":null,"position":8,"is_corresponding":false},{"id":1475881,"name":"Sheilagh Smit","orcid":null,"position":9,"is_corresponding":false},{"id":231934,"name":"Neil Martinson","orcid":"0000-0002-0184-5705","position":10,"is_corresponding":false},{"id":277340,"name":"Kathleen Kahn","orcid":"0000-0003-3339-3931","position":11,"is_corresponding":false},{"id":407346,"name":"Limakatso Lebina","orcid":"0000-0001-6825-0573","position":12,"is_corresponding":false},{"id":227049,"name":"Cheryl Cohen","orcid":"0000-0003-0376-2302","position":13,"is_corresponding":false},{"id":227091,"name":"Anne von Gottberg","orcid":"0000-0002-0243-7455","position":14,"is_corresponding":false},{"id":629773,"name":"Nicole Wolter","orcid":"0000-0002-9526-0133","position":15,"is_corresponding":false},{"id":1092223,"name":"Fahima Moosa","orcid":"0000-0003-0281-3649","position":0,"is_corresponding":true}],"reference_count":28,"raw_metadata":{"citation_network_status":"fetched"},"created_at":"2026-07-19T02:57:07.857542Z","pmid":"40645456","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":[]}