Highly pathogenic avian influenza H5N8 Clade 2.3.4.4B virus in Uganda, 2017

Disentangling the role of Africa in the global spread of H5 highly pathogenic avian influenza

“…Although the three epi-based datasets were built to be fairly balanced in terms of sampling location, collection date and host (Supplementary Methods), the number of sequences from wild birds turned out to be very heterogeneous per region. To overcame this host skewed data for certain geographic areas, such as West and East-Central Africa, South Asia and the Middle East, for which the available sequences from wild birds ranged from 5% (West Africa) to 24% (the Middle East), we repeated the analyses by allowing only host species transitions from wild to domestic birds, as to consider the abundant evidence that during and after 2005, Gs/GD lineage introduction in poultry in multiple regions was associated with wild bird migration 12,13,15,[25][26][27][28][29][30][31][32][33][34][35][36] . Using such enforcement, our estimates reveal a significantly higher rate of viral spread in wild birds compared to domestic ones (Fig.…”

“…The key role of long-distance migrants in the dispersal of HPAI H5 viruses has been suggested by several authors based on phylogenetic analyses, epidemiological investigations and on the timing and direction of the intercontinental spreads, which coincided with fall bird migrations 25,[28][29][30][31][32][33][34][35][36] . Moreover, HPAI H5-infected wild species have been reported in a variety of countries before or simultaneously with poultry outbreaks, and direct or indirect contacts with wild birds have been frequently identified as the most probable cause of virus introduction into poultry 12,13,15,26,27,29,35 . In some African countries, illegal poaching of wild birds, which are kept in rural communities and then sold at markets, is not uncommon and may represent a possible bridge between wild and domestic birds 59 .…”

“…The last incursion of the Gs/GD lineage, clade 2.3.4.4 -group B (2.3.4.4-B), into Africa occurred in November 2016, and for the first time the epidemic spread to several countries in northern, western, eastern, central and southern Africa. Egypt, Tunisia and Nigeria were the first countries reporting the disease [8][9][10] , followed by Niger, Cameroon and Uganda [11][12][13] . In spring 2017, the virus reached the Democratic Republic of the Congo (DR Congo) 14 , Zimbabwe and South Africa 11,15 and in February 2019 new cases were reported in Namibia 16 .…”

Systematic Review of Important Viral Diseases in Africa in Light of the ‘One Health’ Concept

“…To summarize, a high percent positivity has been reported for avian influenza virus, mamastrovirus, Nipah virus, Ntwetwe virus, and WNV from Uganda ( Figure 6). identified a high similarity (99.5%) of Ugandan H5N8 virus sequences with the H5N8 sequences reported from the Democratic Republic of Congo and a relatively lower identity (98.8-99.1%) with the H5N8 virus sequences reported in 2017 from Egypt and South Africa [78]. This observation suggested a bird migration-related spread of H5N8 virus in the African continent.…”

Avian influenza overview August – November 2018

“…The first genetic description of A(H5N8) viruses detected in wild and domestic birds in Uganda in early 2017 was provided by Ndumu et al (2018). The spectrum of affected wild bird species included whitewinged black terns, egrets and grey-headed gulls.…”