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Arthropod vectors are responsible for a multitude of human and animal diseases affecting poor communities in sub-Saharan Africa. Their control still relies on chemical agents, despite growing evidence of insecticide resistance and environmental health concerns. Biorational agents, such as the entomopathogenic fungus <i>Metarhizium anisopliae</i>, might be an alternative for vector control. Recently, the <i>M. anisopliae</i> isolate ICIPE 7 has been developed into a commercial product in Kenya for control of ticks on cattle. We were interested in assessing the potential of controlling not only ticks but also disease-transmitting mosquitoes and tsetse flies using cattle as blood hosts, with the aim of developing a product for integrated vector management. Laboratory bioassays were carried out with <i>M. anisopliae</i>, isolate ICIPE 7 and isolate ICIPE 30, to compare efficacy against laboratory-reared <i>Anopheles arabiensis</i>. ICIPE 7 was further tested against wild <i>Glossina fuscipes</i> and <i>Rhipicephalus</i> spp. Dose–response tests were implemented, period of mosquito exposure was evaluated for effects on time to death, and the number of spores attached to exposed vectors was assessed. Exposure to 10⁹ spores/mL of ICIPE 7 for 10 min resulted in a similar mortality of <i>An. arabiensis</i> as exposure to ICIPE 30, albeit at a slower rate (12 vs. 8 days). The same ICIPE 7 concentration also resulted in mortalities of tsetse flies (LT₅₀: 16 days), tick nymphs (LT₅₀: 11 days), and adult ticks (LT₅₀: 20 days). Mosquito mortality was dose-dependent, with decreasing LT₅₀ of 8 days at a concentration of 10⁶ spores/mL to 6 days at 10¹⁰ spores/mL. Exposure period did not modulate the outcome, 1 min of exposure still resulted in mortality, and spore attachment to vectors was dose-dependent. The laboratory bioassays confirmed that ICIPE 7 has the potential to infect and cause mortality to the three exposed arthropods, though at slower rate, thus requiring further validation under field conditions.