I. INTRODUCTION

 

I. INTRODUCTION
The scabies mite, Sarcoptes scabiei, is an ectoparasite that burrows into the upper layer of the skin and deposits eggs which form adults in 10-17 days.8 On a person, scabies mites can live for as long as 1-2 months. Off a person, scabies mites usually do not survive more than 48-72 hours. An exposed individual can be infectious to others, even in the absence of symptoms which may not appear until 4-6 weeks after exposure. Scabies can spread rapidly under crowded conditions where close body contact is frequent.10

Scabies outbreaks have occurred among patients, visitors, and staff in healthcare settings, particularly in facilities that provide residential or overnight care such as nursing homes, assisted living facilities, and hospitals. Outbreaks frequently are the result of delayed diagnosis and treatment.1 Because it is so highly transmissible, crusted scabies requires rapid and aggressive detection, diagnosis, infection control, and treatment measures to prevent and control spread.11

 

 

 

II. OUTBREAK DETECTION & REPORTING

 

 

 

 

a. Thresholds

  • What is the threshold for additional investigation by a facility?
    1. Single case of scabies (non-crusted or crusted) identified in patients or staff (not applicable to outpatient settings)
  • What is the threshold for reporting to public health? (Check with your local & state public health departments to confirm their reporting requirements.)
    1. Single case of crusted scabies
    2. Two cases of non-crusted scabies identified in patients or staff within the facility in a 2-month period of time
    3. Outpatient or emergency department settings: Single case of crusted or non-crusted scabies in a patient from another facility or other congregate setting
  • What is the outbreak definition?
    1. Two cases of non-crusted or crusted scabies identified in patients or staff on the same unit, or within the facility if an epidemiologic link is identified, within a 2-month period of time. (not applicable to outpatient settings)

 

b. How can detection and reporting be improved?

  • Maintain a high index of suspicion that scabies may be the cause of undiagnosed skin rash; suspected cases should be evaluated and confirmed by obtaining skin scrapings.4

 

 

 

III. INVESTIGATION & CONTROL

 

 

a. Key points for consideration

  • Diagnosis of a scabies infestation usually is made based upon the customary appearance and distribution of the rash and the presence of burrows.12
  • Skin scrapings can be performed and used for microscopic identification of the mite or its products. However, a negative skin scraping from a person with typical non-crusted scabies does not rule out scabies infestation.8
  • If clinical suspicion for scabies infestation is high, but lab confirmation cannot be obtained, investigation should continue and a decision to proceed with treatment should be considered.9
  • Treatment, prophylaxis, and environmental cleaning should all be accomplished within the same 24 hour period to prevent re-infestation of treated or prophylaxed individuals.8
  • During an outbreak, daily patient skin assessments should be performed on the affected unit and documented in the patient’s medical record.8
  • Scabies outbreak management should include planning for personal protective equipment (PPE) including disposable, long sleeve gowns and gloves, and pharmacy supplies.8
  • Appropriate application of scabicide medication is essential. Control measures will be compromised if:
    • scabicide application directions are not followed;
    • scabicide is not applied to the entire body;
    • scabicide is not reapplied after it has been removed from the body during the treatment period; or
    • topical steroids are used during the treatment period.9

 

b. Resources for Investigation and Control Clearinghouse

  • CORHA has identified the following resources and indexed their content based on the subject areas below. The bottom of the table contains hyperlinks to the resources in addition to comments from CORHA that should be reviewed prior to using the resource. Please be sure to check with your health department when investigating this condition to see if any updated guidance is available.
  • CORHA Disclaimer : The CORHA Clearinghouse is a repository of available resources to help public health practitioners. Tools are produced by local, state, and federal agencies, as well as academic institutions and other stakeholders. The contents of this Toolbox are solely the responsibility of the authors and do not necessarily reflect any official recommendations of CIFOR or its partner organizations. CIFOR makes no express or implied warranty with respect to the contents and disclaims liability for any damages arising from or connected to the use of the material in this Toolbox.