Characterization of Bacteria on Aerosols From Dust Events in Dakar, Senegal, West Africa

We identify bacteria types on collected dust samples in Dakar Senegal, a region that experiences frequent Saharan dust events. We use classical techniques to identify bacteria types from dust samples. Seventy‐seven bacteria types are identified from samples collected by spatula and the QuickTake® 30 air sampling pump. The dominant groups in the first batch of 51 bacteria (collected via deposition) are Micrococcus (33.33%), Bacillus (13.73%), Kytococcus (11.76%), Pseudomonas (9.80%), and Burkholderia (7.84%) and dominants in the second batch of 26 bacteria (collected with aerosol sampling vacuum pump): Pseudomonas (38.61%), Burkholderia (26.92%), Micrococcus (11.54%), and Brucella spp (7.69%). These bacteria are found in earlier studies from desert sources and can potentially cause respiratory diseases to exposed populations. Future work will use molecular methods is necessary to search for additional pathogens, including viruses on dust aerosols. Plain Language Summary Bacteria on the surfaces of Saharan dust samples collected from 2013–2016 were analyzed using traditional techniques at Dakar, Senegal. The samples were collected using a spatula and the QuickTake® 30 air sampling pump. The analysis finds some bacteria that are linked to respiratory disease, including Micrococcus, Burkholderia, and Pseudomonas. We believe that the spatula technique may include bacteria such as Bacillus from soils, which was not present in airborne samples. Additional analysis using genomic techniques will assist in better identifying bacteria and potential pathogens, which can impacts West African populations and are transported downstream over long distances to the Caribbean, Southeastern United States, South America, and Europe. Key Points Samples of Saharan dust were collected and analyzed using two sampling techniques for bacteria between 2013 and 2016 in Dakar, Senegal The dominant groups include Micrococcus, Bacillus, Pseudomonas, and Burkholderia, using the two sampling techniques The bacteria can promote respiratory disease and pose a threat to populations in West Africa and downstream across Western Atlantic