Scabies: Application of the Novel Identify-Isolate-Inform Tool for Detection and Management
This article discusses the importance of identifying potential cases of scabies, as it is highly contagious – more specifically in the ED where patients often initially present. As the title suggests, the article discusses the 3I Tool, which stands for Identify-Isolate-Inform. This tool was originally developed for Ebola and modified for use in measles, Middle East Respiratory Syndrome, mumps, Zika, Hepatitis A, pertussis, and interestingly, COVID-19.
It is important to note that signs and symptoms of scabies can differ for each patient depending on time since exposure, degree of infestation, host immunocompetency, and possible co-existence of other skin infections. However, the characteristic presentation is an intense nocturnal pruritic rash with papules and burrows [thin, grey or brown lines about 5mm long], which may be difficult to visualize due to excoriation or secondary infections. Those at highest risk include children, elderly, immunocompromised, and people living in close quarters [i.e. refugee camps] as well as those living in tropical or subtropical climates.
Presumptive diagnosis can be made based on clinical features [nocturnal pruritus, known exposure, or typical appearance and distribution of lesions with burrows]. Though, definitive diagnosis depends on identification of mites, eggs, or fecal matter using light microscopy after skin scraping. The article discuss the burrow ink test where basically a felt tip washable marker or pen is used over the affected area and an alcohol swab is then used to clean the surface ink, and any remaining ink under the skin indicates the presence of scabies burrows. Thus, due to its ease, the test can be helpful in the ED to diagnose scabies. A similar test may also be done where topical tetracycline is applied instead and cleaned with alcohol followed by visualization with a Wood’s lamp.
As mentioned, however, the Identify-Isolate-Inform [3I] Tool has been modified to be used in the ED for patients in whom scabies is suspected. It essentially is an algorithm that begins with identifying suspected cases of scabies based on symptoms, exposure history, and testing as needed, followed by isolating the patient in contact isolation until 8 hours after treatment, and informing the local health authority in cases of outbreak, which is defined as 2 or more consecutive cases of scabies among staff within 4 to 6 weeks, as a means to avoid rapid spread.
