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Introduction: Mosquitoes and ticks are arthropods and are considered to be the main vectors of human and animal diseases worldwide. The aim of this study was to use of matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) to identify ticks and mosquitoes in Côte d’Ivoire. Methods: Ticks were collected from sheep reared at the Institut Pasteur and mosquitoes from the institute's courtyard. Specimens were then identified using morphological and molecular techniques, before MALDI- TOF identification was attempted by testing the obtained spectra against those from an in-house MS arthropod spectra database. Tick-associated bacteria were also identified using molecular tools. Results: 16 and 47 mosquito and tick specimens were used, respectively. Morphologically, mosquitoes were identified to the Culex genus only and ticks were identified as Amblyomma variegatum (n=36; 76.60%) and Rhipicephalus (Boophilus) microplus (n=11; 23.43%) species. MALDI-TOF MS combined with molecular biology showed that 14 of the mosquitoes were Culex quinquefasciatus and the 36 tick specimens were confirmed to be A. variegatum and nine R. (B.) microplus. Tick screening showed the presence of DNA of Rickettsia africae in A. variegatum, and of Ehrlichia canis and Ehrlichia ruminantium in R. (B.) microplus. Conclusion: MALDI-TOF MS is a fast and efficient tool for identifying arthropods. The transfer of MALDI-TOF MS technology and staff training should be encouraged in African countries for use in medical entomology and microbiology. The detection of pathogen DNA in ticks is evidence of the existence and circulation of tick-borne diseases in humans and animals.

Keywords: mosquitoes; ticks; MALDI-TOF MS; Rickettsia sp.; Ehrlichia sp.; Côte d'Ivoire