Characterising spatial patterns of neglected tropical disease transmission using integrated sero-surveillance in Northern Ghana.

Background: As prevalence decreases in pre-elimination settings, identifying the spatial distribution of remaining infections to target control measures becomes increasingly challenging. By measuring multiple antibody responses indicative of past exposure to different pathogens, integrated serological surveys enable simultaneous characterisation of residual transmission of multiple pathogens. Methodology/Principal findings: Here, we combine integrated serological surveys with geostatistical modelling and remote sensing-derived environmental data to estimate the spatial distribution of exposure to multiple diseases in children in Northern Ghana. The study utilised the trachoma surveillance survey platform (cross-sectional two-stage cluster-sampled surveys) to collect information on additional identified diseases at different stages of elimination with minimal additional cost. Geostatistical modelling of serological data allowed identification of areas with high probabilities of recent exposure to diseases of interest, including areas previously unknown to control programmes. We additionally demonstrate how serological surveys can be used to identify areas with exposure to multiple diseases and to prioritise areas with high uncertainty for future surveys. Modelled estimates of cluster-level prevalence were strongly correlated with more operationally feasible metrics of antibody responses. Conclusions/Significance: This study demonstrates the potential of integrated serological surveillance to characterise spatial distributions of exposure to multiple pathogens in low transmission and elimination settings when the probability of detecting infections is low. Author summary: Following implementation of successful interventions, one of the primary challenges for neglected tropical disease programmes is identifying areas with remaining disease transmission. As disease prevalence decreases, these infections become increasingly rare and hard to detect. Serological assays measure long-lived disease-specific antibody responses indicating past exposure to pathogens and increase the probability of detecting disease transmission. Here, we integrate serological assays with environmental and spatial data to map priority areas for surveillance for multiple neglected tropical diseases in Northern Ghana using the two-stage cluster-based survey platform established for trachoma surveillance. The use of multiplex bead assays measuring exposure to multiple pathogens allows integrated surveillance of diseases of interest to the national control programme. We identify areas with high risks of transmission to selected diseases as well as areas with high uncertainty which are priorities for future control and surveillance efforts. Together, this highlights the utility of multiplex serological platforms as a tool for integrated surveillance and mapping of neglected tropical diseases. [ABSTRACT FROM AUTHOR]