A comprehensive systematic review of sarcoptic mange diagnostic methods in wildlife

Sarcoptic mange is a parasitic contagious disease that can lead to significant declines in wildlife populations. To identify the most used methods for diagnosing mange in free-ranging wildlife species, a systematic review was conducted across multiple databases: Scopus, PubMed, Web of Science, ProQuest Central and CABI. Citation screening was performed using the web-based platform, Covidence. A customized data extraction form, developed by the authors, was used to collect relevant information. This information was later exported and analyzed using Microsoft Excel. The objectives of this systematic review were to identify the most used detection methods for sarcoptic mange in wildlife globally over the past 30 years, classify them into invasive and non-invasive categories and provide an updated overview of related adjunct techniques and the broader scientific literature on mange detection and documentation in free-ranging animals. A total of 228 studies were analyzed and categorized into two groups-non-invasive and invasive methods. Non-invasive methods (visual observation, camera trapping, spotlighting, detector dogs and infrared thermography) do not require restraining of animals. Invasive methods (skin scraping, molecular diagnosis using mite isolation and polymerase chain reaction (PCR), serological diagnosis using Enzyme Linked ImmunoSorbent Assay (ELISA), histological analysis and immunohistochemistry) typically require taking samples from the animals and clinical or laboratory infrastructure. Across all diagnostic methods, visual observation was the most widely used technique, followed by skin scraping as the second most frequently applied method for confirming sarcoptic mange. Non-invasive approaches like spotlighting and camera traps provided valuable population-level insights without direct animal contact, though laboratory methods such as PCR, ELISA, and histological analysis offered greater accuracy at higher costs. We recommend a combined approach, starting with non-invasive methods to assess overall population health before using invasive techniques on selected animals for definitive diagnosis, with advanced technologies expected to enhance long-range detection capabilities in the future.