Cambodia has been validated for eliminating LF since 2016 and for eliminating both measles and maternal and neonatal tetanus since 2015. These are tremendous achievements; however, recent drops in coverage for vaccine preventable diseases threatens some these gains and there is a need to conduct surveillance to ensure that gains are sustained and that there is no recrudescence in the high risk areas. Integrated serosurveillance in Cambodia would provide substantial cost savings over disease-specific surveys, is logistically easier, and is less disruptive for communities. Serosurveys can provide rich information on exposure patterns for NTDs as well as a measure of population-level immunity to VPDs (and hence may serve as a validation of coverage). In this study, the team in Cambodia will revisit 2 historically high risk provinces in the north. This study builds on the work of a 2012 national serosurvey, which found that this northern region had the highest LF antibody response and is consequently considered to be at highest risk for re-emergence of LF. This study will be an integrated assessment of tetanus and other VPDs (measles, rubella, diphtheria), as well as malaria.