Blackflies as a medical threat to military working dogs: A case study on surveillance, management, and vector potential

Military working dogs (MWDs) perform critical tasks across the US Armed Forces and threats to their health impact military readiness. Joint Base San Antonio (JBSA)-Lackland is the hub of MWD training across U.S. Armed Forces, but the area hosts a diverse array of entomological threats and vectors. In February 2023, multiple Belgium Malinois MWDs presented with unknown bites and allergic reactions. U.S. Army Public Health Command-Central responded to these complaints and identified the cause of the bites as the blackfly Simulium mediovittatum Knab. We implemented a surveillance program to characterize larval and adult abundance. A nearby water treatment facility provides a flow rate for riffles that can support continuous larval generations throughout the year. We collaborated with installation officials to develop a management plan. While S. mediovitattum is known to be mammalophilic, this is the first record of them attacking domestic dogs. This host association raises questions about the possibility that S. mediovittatum could vector Onchocerca lupi, an emerging, zoonotic filaroid nematode. This case study highlights a regional military public health assets’ ability to collaborate across branches to maintain force health protection.