First detection of echovirus 18 associated with aseptic meningitis in a child in Niger Republic, 2024: a case report.

BACKGROUND: Viral meningitis is an inflammation of the meninges that cause substantial morbidity and mortality in young children worldwide. Echovirus 18 (E18) has been recognized as an important causative pathogen of aseptic meningitis and recombinant strains have been associated with severe cases. Herein, we report the detection of E18 associated with aseptic meningitis in a child with a sickle cell anemia from Niger Republic in December 2024. CASE PRESENTATION: On November 19th, 2024, a 13-year-old boy returning from travel in a neighboring country was admitted at the National Reference Center for Sickle Cell Anemia (CNRD) in Niamey, following a severe anaemia combined with renal failure and hepatic dysfunction. Despite the efforts of medical care and compensatory treatment, he died six days after the onset of symptoms including a constantly high fever with persistent headaches and febrile convulsions, suggesting an aseptic meningitis. Further laboratory tests on blood sample using whole genome sequencing at Pasteur Institute of Dakar, confirmed the echovirus 18 virus as the etiological agent. CONCLUSION: This is the first reported case of E18-associated with aseptic meningitis in Niger and the patient's death could be associated with the underlying co-morbidity of sickle cell anemia SS form. Our findings point the need for strengthening the surveillance of viral etiologies of meningitis in Niger. More studies are needed to predict and mitigate the re-emergence risk and gain a better insight into the prevalence and molecular epidemiology of E18 over time.