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The article discusses quantification of the reporting of avian diseases, particularly those suggesting highly pathogenic avian influenza (HPAI), by poultry owners in Mali. It describes deficiencies in the National Veterinary Epidemiologic Surveillance Network of Mali's domestic and wild bird surveillance that was implemented in response to influenza outbreaks from HPAI throughout western Africa. Major constraints affecting the likelihood of HPAI signs being reported are addressed.

Mali is a country where little information is known about the circulation of avian influenza viruses (AIVs) in poultry. Implementing risk-based surveillance strategies would allow early detection and rapid control of AIVs outbreaks in the country. In this study, we implemented a multi-criteria decision analysis (MCDA) method coupled with geographic information systems (GIS) to identify risk areas for AIVs occurrence in domestic poultry in Mali. Five risk factors associated with AIVs occurrence were identified from the literature, and their relative weights were determined using the analytic hierarchy process (AHP). Spatial data were collected for each risk factor and processed to produce risk maps for AIVs outbreaks using a weighted linear combination (WLC). We identified the southeast regions (Bamako and Sikasso) and the central region (Mopti) as areas with the highest risk of AIVs occurrence. Conversely, northern regions were considered low-risk areas. The risk areas agree with the location of HPAI outbreaks in Mali. This study provides the first risk map using the GIS-MCDA approach to identify risk areas for AIVs occurrence in Mali. It should provide a basis for designing risk-based and more cost-effective surveillance strategies for the early detection of avian influenza outbreaks in Mali.

The geographical distribution and impact on animal and human health of both West Nile and Usutu viruses, two flaviviruses of the Japanese encephalitis complex, have been increasing during the past two decades. Both viruses circulate in Europe and Africa within a natural cycle between wild birds and mosquitoes, mainly from the Culex genus. We retrospectively analyzed sera from domestic and wild birds sampled in 2008 in two wetlands, namely the Inner Niger Delta, Mali, and the Lake Alaotra area, Madagascar. Sera were first tested using a commercial ID Screen West Nile Competition Multi-species ELISA kit. Then, positive sera and sera with insufficient volume for testing with ELISA were tested with a Microneutralization Test. In Mali, the observed seroprevalence in domestic birds was 28.5% [24.5; 32.8] 95%CI , 3.1 % [1.8; 5.2] 95%CI , 6.2% [3.4; 10.2] 95%CI and 9.8 % [7.3; 12.8] 95%CI , for West Nile virus (WNV), Usutu virus (USUV), undetermined flavivirus, and WNV/USUV respectively. Regarding domestic birds of Madagascar, the observed seroprevalence was 4.4 % [2.1; 7.9] 95%CI for WNV, 0.9% [0.1; 3.1] 95%CI for USUV, 1.3% [0.5; 2.8] 95%CI for undetermined flavivirus, and null for WNV/USUV. Among the 150 wild birds sampled in Madagascar, two fulvous whistling-ducks ( Dendrocygna bicolor ) were positive for WNV and two for an undetermined flavivirus. One white-faced whistling-duck ( Dendrocygna viduata ) and one Hottentot teal ( Spatula hottentota ) were tested positive for USUV. African and European wetlands are linked by wild bird migrations. This first detection of USUV-as well as the confirmed circulation of WNV in domestic birds of two wetlands of Mali and Madagascar-emphasizes the need to improve the surveillance, knowledge of epidemiological patterns, and phylogenetic characteristics of flavivirus in Africa, particularly in areas prone to sustained, intense flavivirus transmission such as wetlands.

This study reports the first evidence of circulation of avian influenza viruses (AIV) in domestic poultry in Mali. In the Mopti region, where AIV have already been isolated in migratory water birds, we sampled 223 backyard domestic birds potentially in contact with wild birds and found that 3.6% had tracheal or cloacal swabs positive by real-time reverse transcription PCR (rRT-PCR) for type A influenza viruses (IVA) and that 13.7% had sera positive by commercial ELISA test detecting antibodies against IVA. None of the birds positive by rRT-PCR for IVA was positive by rRT-PCR for H5 and H7 subtypes, and none showed any clinical signs therefore indicating the circulation of low pathogenic avian influenza. Unfortunately, no virus isolation was possible. Further studies are needed to assess the temporal evolution of AIV circulation in the Mopti region and its possible correlation with the presence of wild birds.