Yellow fever (YF) is a serious infectious hemorrhagic disease without treatment due to the Amaril virus transmitted to humans by infected mosquitoes. There is an inexpensive and effective YF vaccine. Urban populations living in areas with high concentrations and low YF immunization coverage are most at risk. Niger is one of the countries at high risk of an YF epidemic. It is a reportable disease monitored on a &quot;case by case&quot; basis. Niamey is the largest city in Niger, with 88.8% AAV coverage in 2021.The objective was to evaluate the YF surveillance system in this region.