Molecular characterization of peste des petits ruminants virus and Mycoplasma capricolum subsp. capripneumoniae in small ruminants in northern Mauritania, 2023.

Global eradication of peste des petits ruminants (PPR) is planned for 2030 by international animal health organizations in collaboration with national partners. As the deadline approaches, it is fundamental that the PPR status in each country is determined. In addition, the identification of other pathogens of small ruminants that share common geographical locations and can produce similar clinical signs is also important for differential diagnosis. With this in mind, 37 samples collected from goats and sheep presenting respiratory symptoms in Mauritania in 2023 were screened for the presence of PPR virus, Capripoxvirus, Pasteurella multocida and Mycoplasma capricolum subspecies capripneumoniae (Mccp) using a one-step multiplex RT-qPCR assay. None of the samples were positive for Capripoxvirus or P. multocida. Nine of them were positive for PPRV and sequence analysis of a segment of the PPRV nucleoprotein revealed that they belonged to lineage IV and were similar to viruses recently identified in Côte D'Ivoire, Guinea, and Niger indicating transboundary movement. The full genome of one representative virus was also generated. Mccp was identified in eight samples and multi-locus sequence analysis (MLSA) identified them as belonging to MLSA Group 3 together with Mccps identified in China, Tajikistan, Turkey and the United Arab Emirates. This is the first time that such a study has been undertaken in Mauritania and the data generated should be of interest to those involved in the management of goat diseases in Mauritania and neighbouring countries.

Avian influenza H5N1 in a great white pelican (Pelecanus onocrotalus), Mauritania 2022.

In February 2022, mortalities among great white pelicans (Pelecanus onocrotalus) were reported in the Parc National de Diawling, southwestern Mauritania. Samples were collected and processed, indicating the presence of high pathogenicity avian influenza subtype H5N1. A nearly complete genome was generated for one sample, revealing a high similarity [> 99.5% (H5) nucleotide sequence identity] with Clade 2.3.4.4b H5N1 identified in Europe in 2022.

Mosquito survey in Mauritania: Detection of Rift Valley fever virus and dengue virus and the determination of feeding patterns.

In Mauritania, several mosquito-borne viruses have been reported that can cause devastating diseases in animals and humans. However, monitoring data on their occurrence and local distribution are limited. Rift Valley fever virus (RVFV) is an arthropod-borne virus that causes major outbreaks throughout the African continent and the Arabian Peninsula. The first Rift Valley fever (RVF) epidemic in Mauritania occurred in 1987 and since then the country has been affected by recurrent outbreaks of the disease. To gain information on the occurrence of RVFV as well as other mosquito-borne viruses and their vectors in Mauritania, we collected and examined 4,950 mosquitoes, belonging to four genera and 14 species. The mosquitoes were captured during 2018 in the capital Nouakchott and in southern parts of Mauritania. Evidence of RVFV was found in a mosquito pool of female Anopheles pharoensis mosquitoes collected in December on a farm near the Senegal River. At that time, 37.5% of 16 tested Montbéliarde cattle on the farm showed RVFV-specific IgM antibodies. Additionally, we detected IgM antibodies in 10.7% of 28 indigenous cattle that had been sampled on the same farm one month earlier. To obtain information on potential RVFV reservoir hosts, blood meals of captured engorged mosquitoes were analyzed. The mosquitoes mainly fed on humans (urban areas) and cattle (rural areas), but also on small ruminants, donkeys, cats, dogs and straw-colored fruit bats. Results of this study demonstrate the circulation of RVFV in Mauritania and thus the need for further research to investigate the distribution of the virus and its vectors. Furthermore, factors that may contribute to its maintenance should be analyzed more closely. In addition, two mosquito pools containing Aedes aegypti and Culex quinquefasciatus mosquitoes showed evidence of dengue virus (DENV) 2 circulation in the city of Rosso. Further studies are therefore needed to also examine DENV circulation in Mauritania.