Background
Seasonal influenza is a crucial public health concern. Recent populationalstudies, confirmed the involvement of several signaling proteins on the outcome of theinfection. The IFITM3 and IFNAR2 variants, play acritical role in the host’sinnate immune response.The current study aims to evaluate the association between the IFITM3 rs12252 and IFNAR2rs2236757 variants with the risk of developing Severe Acute Respiratory Infection (SARI) orInfluenza-Like Illness (ILI) in Moroccan patients infected with influenza virus.

Methods
A comparative case-control study was conducted based on an existing sentinel system forvirological surveillance of influenza respiratory viruses. From August 25, 2023, to April 17,2024, a total of 1,925 nasopharyngeal swabs were collected from patients who met the World Health Organization case definitions for SARI and ILI. A group of healthy individuals were included as a control group. Influenza infection was diagnosed using qRT-PCR in accordance with the US-CDC protocol. Genotyping of the IFITM3 rs12252 and IFNAR2 rs2236757 variant was carried-out using TaqMan SNP Genotyping Assays.did not find it Statistical data analysis was performed using SNPStats and MedCalc software.

Results
Genetic analysis revealed a significant association between the IFITM3 rs12252 variants and the severe syndrome (SARI). Carriers of the AG/GG genotypes had a significantly higher risk of hospitalization for SARI patients compared to those with other genotypes; the adjusted odds ratio (OR) ranged from 2.66 to 12.66 (p-value?
Conclusions
A strong association of the IFITM3 rs12252 variant was confirmed among SARI patients, but not among ILI ones. The IFNAR2 rs2236757, however, did not show any association between flu infection and the clinical outcome.