Effects of Accounting for Interval-Censored Antibody Titer Decay on Seroincidence in a Longitudinal Cohort Study of Leptospirosis
| Autor: | Katharine A Owers Bonner, Jaqueline S. Cruz, James E. Childs, Mayara Carvalho, Federico Costa, Daiana de Oliveira, Albert I. Ko, Peter J. Diggle, Nivison Nery, Gielson Almeida do Sacramento |
|---|---|
| Jazyk: | angličtina |
| Rok vydání: | 2020 |
| Předmět: |
Epidemiology
030231 tropical medicine Accounting 03 medical and health sciences 0302 clinical medicine Risk Factors Seroepidemiologic Studies Direct agglutination test Medicine Humans Leptospirosis Longitudinal Studies Seroconversion 030304 developmental biology 0303 health sciences business.industry Incidence Antibody titer Original Contribution medicine.disease Confidence interval Titer Italy Sample size determination Cohort business Brazil |
| Zdroj: | Am J Epidemiol |
| Popis: | Accurate measurements of seroincidence are critical for infections undercounted by reported cases, such as influenza, arboviral diseases, and leptospirosis. However, conventional methods of interpreting paired serological samples do not account for antibody titer decay, resulting in underestimated seroincidence rates. To improve interpretation of paired sera, we modeled exponential decay of interval-censored microscopic agglutination test titers using a historical data set of leptospirosis cases traced to a point source exposure in Italy in 1984. We then applied that decay rate to a longitudinal cohort study conducted in a high-transmission setting in Salvador, Brazil (2013–2015). We estimated a decay constant of 0.926 (95% confidence interval: 0.918, 0.934) titer dilutions per month. Accounting for decay in the cohort increased the mean infection rate to 1.21 times the conventionally defined rate over 6-month intervals (range, 1.10–1.36) and 1.82 times that rate over 12-month intervals (range, 1.65–2.07). Improved estimates of infection in longitudinal data have broad epidemiologic implications, including comparing studies with different sampling intervals, improving sample size estimation, and determining risk factors for infection and the role of acquired immunity. Our method of estimating and accounting for titer decay is generalizable to other infections defined using interval-censored serological assays. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|