Recrudescence of yellow fever in Chad: Case report of the last confirmed case in the health district of Lai-Chad

Yellow fever (YF) is a viral haemorrhagic fever caused by yellow fever virus transmitted by Aedes mosquitoes. Since 2013, in Chad, four cases of yellow fever have been detected and confirmed as part of the national fever surveillance program. We here report the last clinical case confirmed in the health district of Lai. The patient was a 57-year-old man with no significant medical and surgical history and unknown immunisation status. He consulted on April 21st, 2020 for fever, moderate to low abundance jaundice and epistaxis (nosebleed) and painful hepatomegaly. Paraclinical examinations, such as RT-PCR, objectified yellow fever virus in post-mortem tissue sample. Thus, confirmed yellow fever cases in this district, the low level of vaccination coverage, the circulation of the virus and the presence of vector in the country should warn of a real threat of reemergence of yellow fever in Chad.