Circulation and seasonality of influenza viruses in different transmission zones in Africa.

Autor: Belizaire MRD; School of Medicine, University of Alcalá, Madrid, Spain. darnyckabelizaire@gmail.com., N'gattia AK; National Institute of Public Hygiene, Ministry of Health, Abidjan, Côte d'Ivoire., Wassonguema B; Inserm, ECEVE, Université Paris Cité, 75010, Paris, France., Simaleko MM; Faculty of Medical Sciences, University of Bangui, Bangui, Central African Republic., Nakoune E; Laboratory for Arboviruses, Viral Hemorrhagic Fevers Viral Hemorrhagic Fevers, Emerging Viruses and Zoonoses, Institut Pasteur de Bangui, Bangui, Central African Republic., Rafaï C; National Laboratory and Clinical Analysis, Ministry of Public Health and Population, Bangui, Central African Republic., Lô B; Faculty of Medicine, University of Nouakchott Al Assriya, Nouakchott, Mauritania., Bolumar F; School of Medicine, University of Alcalá, Madrid, Spain.; Department of Epidemiology and Biostatistics, Graduate School of Public Health, City University of New York, New York, USA.
Jazyk: angličtina
Zdroj: BMC infectious diseases [BMC Infect Dis] 2022 Nov 07; Vol. 22 (1), pp. 820. Date of Electronic Publication: 2022 Nov 07.
DOI: 10.1186/s12879-022-07727-2
Abstrakt: Background: Influenza is responsible for more than 5 million severe cases and 290,000 to 650,000 deaths every year worldwide. Developing countries account for 99% of influenza deaths in children under 5 years of age. This paper aimed to determine the dynamics of influenza viruses in African transmission areas to identify regional seasonality for appropriate decision-making and the development of regional preparedness and response strategies.
Methods: We used data from the WHO FluMart website collected by National Influenza Centers for seven transmission periods (2013-2019). We calculated weekly proportions of positive influenza cases and determined transmission trends in African countries to determine the seasonality.
Results: From 2013 to 2019, influenza A(H1N1)pdm2009, A(H3N2), and A(H5N1) viruses, as well as influenza B Victoria and Yamagata lineages, circulated in African regions. Influenza A(H1N1)pdm2009 and A(H3N2) highly circulated in northern and southern Africa regions. Influenza activity followed annual and regional variations. In the tropical zone, from eastern to western via the middle regions, influenza activities were marked by the predominance of influenza A subtypes despite the circulation of B lineages. One season was identified for both the southern and northern regions of Africa. In the eastern zone, four influenza seasons were differentiated, and three were differentiated in the western zone.
Conclusion: Circulation dynamics determined five intense influenza activity zones in Africa. In the tropics, influenza virus circulation waves move from the east to the west, while alternative seasons have been identified in northern and southern temperate zones. Health authorities from countries with the same transmission zone, even in the absence of local data based on an established surveillance system, should implement concerted preparedness and control activities, such as vaccination.
(© 2022. The Author(s).)
Databáze: MEDLINE
Externí odkaz:
Nepřihlášeným uživatelům se plný text nezobrazuje