Journal Article

The epidemiological signature of influenza B virus and its B/Victoria and B/Yamagata lineages in the 21st century

Peng, Zhibin, Higueros, Rocio, Holubka, Olha, Bresee, Joseph, Arévalo, Brechla Moreno, Araya, Jenny Lara, Wood, Tim, Lee, Vernon Jian Ming, Kusznierz, Gabriela, Donker, Gé A., Chaves, Sandra S., Huang, Q. Sue, Kosasih, Herman, Castrucci, Maria Rita, Meijer, Adam, El Falaki, Fatima, Palekar, Rakhee, Fasce, Rodrigo A., Guiomar, Raquel, Bessonova, Olga, Rivera, Rudevelinda, Cohen, Cheryl, Bella, Antonino, El Guerche-Séblain, Clotilde, Mironenko, Alla, Caini, Saverio, Le, Mai T. Q., Bustos, Patricia, Barakat, Amal, Rodrigues, Ana Paula, Pebody, Richard, Ferreira de Almeida, Walquiria Aparecida, Ang, Li Wei, Emukule, Gideon O., Njouom, Richard, de Paula Júnior, Francisco José, Barahona de Gámez, Mónica Jeannette, Daouda, Coulibaly, Treurnicht, Florette, Makusheva, Ainash, Garate, Verònica Vera, Heraud, Jean-Michel, Zambon, Maria, Thapa, Binay, Brammer, Lynnette, Feng, Luzhao, Kadjo, Hervé A., Razanajatovo, Norosoa H., Hoang, Phuong V. M., Bruno, Alfredo, de Mora, Doménica, Wangchuk, Sonam, Balmaseda, Angel, Paget, John

2019

Overview

We describe the epidemiological characteristics, pattern of circulation, and geographical distribution of influenza B viruses and its lineages using data from the Global Influenza B Study. We included over 1.8 million influenza cases occurred in thirty-one countries during 2000-2018. We calculated the proportion of cases caused by influenza B and its lineages; determined the timing of influenza A and B epidemics; compared the age distribution of B/Victoria and B/Yamagata cases; and evaluated the frequency of lineage-level mismatch for the trivalent vaccine. The median proportion of influenza cases caused by influenza B virus was 23.4%, with a tendency (borderline statistical significance, p = 0.060) to be higher in tropical vs. temperate countries. Influenza B was the dominant virus type in about one every seven seasons. In temperate countries, influenza B epidemics occurred on average three weeks later than influenza A epidemics; no consistent pattern emerged in the tropics. The two B lineages caused a comparable proportion of influenza B cases globally, however the B/Yamagata was more frequent in temperate countries, and the B/Victoria in the tropics (p = 0.048). B/Yamagata patients were significantly older than B/Victoria patients in almost all countries. A lineage-level vaccine mismatch was observed in over 40% of seasons in temperate countries and in 30% of seasons in the tropics. The type B virus caused a substantial proportion of influenza infections globally in the 21st century, and its two virus lineages differed in terms of age and geographical distribution of patients. These findings will help inform health policy decisions aiming to reduce disease burden associated with seasonal influenza.

• Publisher: Public Library of Science,Public Library of Science (PLoS)
• Subject: Biochemistry, Molecular Biology / Biology and life sciences / Earth sciences / Emerging diseases / Epidemics / Epidemics - history / Epidemics - statistics & numerical data / Epidemiological Monitoring / Female / History, 21st Century / Human health and pathology / Humans / Infectious diseases / Influenza A virus / Influenza A virus - immunology / Influenza A Virus, H1N1 Subtype / Influenza A Virus, H1N1 Subtype - immunology / Influenza B virus / Influenza B virus - immunology / Influenza B virus - metabolism / Influenza B virus - pathogenicity / Influenza Vaccines / Influenza Vaccines - immunology / Influenza, Human / Influenza, Human - epidemiology / Influenza, Human - history / Life Sciences / Male / Medicine and Health Sciences / Microbiology and Parasitology / Molecular biology / Population Surveillance / Population Surveillance - methods / Santé publique et épidémiologie / Seasons / Virology