Epidemiology and Molecular Analyses of Influenza B Viruses in Senegal from 2010 to 2019

Cheikh Talibouya Touré (1, 2) , Amary Fall (1) , Soa Fy Andriamandimby (3) , Mamadou Malado Jallow (1, 2) , Deborah Goudiaby (1) , Davy Kiori (1) , Sara Sy (1) , Yague Diaw (1) , Koba Ndiende Ndiaye (1) , Fatimata Mbaye (2) , Mbayang Ndiaye Niang (1) , Jean‐michel Heraud (1) , Ndongo Dia (1)

1 Institut Pasteur de Dakar
2 UCAD - Université Cheikh Anta Diop de Dakar [Sénégal]
3 Institut Pasteur de Madagascar

Influenza virus types A and B are responsible for acute viral infections that affect annually 1 billion people, with 290,000 to 650,000 deaths worldwide. In this study, we investigated the circulation of influenza B viruses over a 10-year period (2010–2019). Specimens from patients suspected of influenza infection were collected. Influenza detection was performed following RNA extraction and real-time RT-PCR. Genes coding for hemagglutinin (HA) and neuraminidase (NA) of influenza B viruses were partially sequenced, and phylogenetic analyses were carried out subsequently. During the study period, we received and tested a total of 15,156 specimens. Influenza B virus was detected in 1322 (8.7%) specimens. The mean age of influenza B positive patients was 10.9 years. When compared to reference viruses, HA genes from Senegalese circulating viruses showed deletions in the HA1 region. Phylogenetic analysis highlighted the co-circulation of B/Victoria and B/Yamagata lineage viruses with reassortant viruses. We also noted a clear seasonal pattern of circulation of influenza B viruses in Senegal.

Mots clés: influenza B; surveillance; epidemiology; phylogenetic analyses; reassorting viruses; Senegal; Africa; influenza B

Domaines: Virologie; Systématique, phylogénie et taxonomie; Maladies infectieuses; Maladies émergentes; Santé publique et épidémiologie

Cheikh Talibouya Touré, Amary Fall, Soa Fy Andriamandimby, Mamadou Malado Jallow, Deborah Goudiaby, et al.. Epidemiology and Molecular Analyses of Influenza B Viruses in Senegal from 2010 to 2019. Viruses, 2022, 14 (5), pp.1063. ⟨10.3390/v14051063⟩. ⟨hal-03691695⟩