A longitudinal cohort study of malaria exposure and changing serostatus in a malaria endemic area of rural Tanzania

Malaria Journal

Research

Elizabeth L. Turner¹  Ryan A. Simmons¹  Alison Morris²  Gillian Stresman²  Chris Drakeley²  Marie Lynn Miranda³  Randall Kramer⁴  Wendy P. O’Meara⁴  Leonard Mboera⁵ 

[1] Department of Biostatistics and Bioinformatics, Duke University Medical Center, 2721, 27701, Durham, NC, USA;Duke Global Health Institute, Duke University, 310 Trent Drive, 27701, Durham, NC, USA;Department of Immunology and Infection, London School of Hygiene and Tropical Medicine, Keppel Street, WC1E 7HT, London, UK;Department of Statistics, Rice University, Houston, TX, USA;Duke Global Health Institute, Duke University, 310 Trent Drive, 27701, Durham, NC, USA;National Institute for Medical Research, P.O. Box 9653, 3 Barack Obama Drive, 11101, Dar es Salaam, United Republic of Tanzania;

关键词: Serology;    AMA-1;    MSP-1;    Malaria;   

DOI  :  10.1186/s12936-017-1945-2

 received in 2017-04-13, accepted in 2017-07-18,  发布年份 2017

来源: Springer

【 摘 要 】

BackgroundMeasurements of anti-malarial antibodies are increasingly used as a proxy of transmission intensity. Most serological surveys are based on the use of cross-sectional data that, when age-stratified, approximates historical patterns of transmission within a population. Comparatively few studies leverage longitudinal data to explicitly relate individual infection events with subsequent antibody responses.MethodsThe occurrence of seroconversion and seroreversion events for two Plasmodium falciparum asexual stage antigens (MSP-1 and AMA-1) was examined using three annual measurements of 691 individuals from a cohort of individuals in a malaria-endemic area of rural east-central Tanzania. Mixed-effect logistic regression models were employed to determine factors associated with changes in serostatus over time.ResultsWhile the expected population-level relationship between seroprevalence and disease incidence was observed, on an individual level the relationship between individual infections and the antibody response was complex. MSP-1 antibody responses were more dynamic in response to the occurrence and resolution of infection events than AMA-1, while the latter was more correlated with consecutive infections. The MSP-1 antibody response to an observed infection seemed to decay faster over time than the corresponding AMA-1 response. Surprisingly, there was no evidence of an age effect on the occurrence of a conversion or reversion event.ConclusionsWhile the population-level results concur with previously published sero-epidemiological surveys, the individual-level results highlight the more complex relationship between detected infections and antibody dynamics than can be analysed using cross-sectional data. The longitudinal analysis of serological data may provide a powerful tool for teasing apart the complex relationship between infection events and the corresponding immune response, thereby improving the ability to rapidly assess the success or failure of malaria control programmes.

【 授权许可】

CC BY   
© The Author(s) 2017