Exposure of Humans to Attacks by Deer Keds and Consequences of Their Bites—A Case Report with Environmental Background

SIMPLE SUMMARY: Lipoptena species, also named the deer ked or deer fly, are commonly encountered in temperate areas of Europe, northern China, and North America. Although wild animals seem to be the preferred hosts of these parasitic arthropods, it is increasingly being noted that humans are also directly threatened by their bites. Skin lesions evolving after Lipoptena bites are painful and often lead to the development of inflammation of the skin. Lipoptena species also pose a threat to the health of the host by transferring pathogenic factors, e.g., Bartonella schoenbuchensis, Borrelia burgdorferi, and Anaplasma phagocytophilum. For this reason, knowledge of symptoms caused by Lipoptena bites is worth promoting among not only scientists but also the general public. ABSTRACT: Insects of the genus Lipoptena, e.g., Lipoptena cervi and Lipoptena fortisetosa, are hematophagic ectoparasites mainly attacking deer, roe deer, moose, horses, and cattle. Humans may also be incidental hosts for these insects. The species are vectors of numerous pathogens, including Bartonella schoenbuchensis, Borrelia burgdorferi, and Anaplasma phagocytophilum. Due to the short time of feeding on humans, usually painless bites, and an initially small trace at the site of the bite, the symptoms reported by the patient may not be associated with deer ked infestation and infection with pathogens transmitted by these arthropods. The aim of the study was to describe the consequences of L. cervi bites in humans with detailed documentation of the development of skin lesions. The knowledge about skin lesions arising after deer ked bites may be useful in clinical practice for monitoring patients for the presence of pathogens transmitted by the parasites.