 This research project aims to assess the level of immunity against vaccine-preventable diseases in Timor-Lechte. The study will use a combination of serological surveillance and community-based sampling to collect serum samples from 5,600 people aged one year and older. The results will provide valuable information on the current levels of immunity in the country, which could help inform public health policies and decisions regarding vaccinations. This article was authored by Michael David, Jennifer Yang, Christine McCartney, and others.