Reporting & Investigation of Measles

Table of Contents

A.  Purpose of Surveillance and Reporting

  • To identify all cases and susceptible exposed people rapidly and to prevent additional cases and further transmission of this highly contagious disease.

  • To identify the source of infection so as to better understand how and why the case(s) occurred.

  • To help in the international effort to eliminate indigenous transmission of measles from the Western Hemisphere.

B.  Laboratory and Healthcare Provider Reporting Requirements 

Iowa Administrative Code 641-1.3(139) stipulates that the laboratory and the healthcare provider immediately report any suspected or confirmed case. The reporting number for IDPH Center for Acute Disease Epidemiology (CADE) is (800) 362-2736. After business hours, call the Iowa State Patrol Office at (515) 323-4360 and they will page a member of the on-call CADE staff.

What to Report to the Iowa Department of Public Health

  • A suspect case of measles, as diagnosed by a healthcare provider, or

  • Positive IgM serologic test or PCR test for measles

Case Investigation

Iowa Administrative Code 641-1.3(139) stipulates that the laboratory and the healthcare provider report. Measles is an immediately reportable disease. Call the reporting number for IDPH Center for Acute Disease Epidemiology (CADE) at (800) 362-2736 immediately upon identifying a suspect measles case.

After completing the investigation and gathering case information, enter the information into the Iowa Disease Surveillance System (IDSS), or FAX the report form with supporting laboratory documentation to (515) 281-5698 or mail (in an envelope marked “Confidential”) to the IDPH/CADE, mailing address:

Iowa Department of Public Health, CADE
Lucas State Office Building, 5th Floor
321 E. 12th St.
Des Moines, IA 50319-0075

Laboratory Testing Services Available

Suspect measles cases should be reported immediately to the Iowa Department of Public Health, Center for Acute Disease Epidemiology (CADE) at (800) 362-2736 or after hours, 515-323-4360. Atthat time, CADE will consult on appropriate testing to be ordered and specimen transport to the State Hygienic Laboratory (SHL). Public health response should not be delayed pending the return of laboratory results.

By using the Iowa SHL, transport time is significantly less, and results can be obtained more quickly.

When submitting specimens to SHL, check the box in the demographics section of the order form, directly below the clinician’s phone number and signature. This indicates the testing is being completed because of an imminent public health threat and the test will be performed without charge to the patient. CADE Epidemiologists will provide a test request form.  

Blood Specimen for SHL IgG Testing

  • Prefer serum (min 500ul)  or can send 4-6ml whole blood in a red top or serum separator tube, for infants 2-3ml acceptable and fill out Serology test request form

Throat Swab for PCR

Specimens for measles PCR should ideally be obtained within five days of rash onset.  A throat swab should not be collected any more than 9 days from rash onset.

Viral RNA is more likely to be detected when the specimen is collected as soon as possible after rash onset.

Specimen Types Vary:

  • On day 0-5 of rash, collect a throat swab*

* If a throat swab cannot be collected, a nasopharyngeal specimen can be sent instead; however, a throat swab is the preferred specimen.  

**If date of specimen collection is already more than nine days past rash onset, PCR is not valid.

Collection instructions for PCR

A throat swab is preferred. Nasal/NP swabs or washes are acceptable but not preferred.

Throat swab: Swab tonsillar areas and posterior nasopharynx. Use tongue blade to depress tongue to prevent contamination of swab with saliva. Place swab into 2-3 ml of transport media.

Appropriate swabs and media:

  • Dacron swabs, flocked swabs

  • Viral transport medium (VTM)

Inappropriate swabs:

  • Wood-tipped applicators, Cotton-tipped swabs, Calcium-alginate tipped swabs, Charcoal swabs, Gel swabs

  • Dry swabs are not acceptable

Shipment of specimens

Store/ship specimens at refrigeration temperature (2-8͒ C).  IDPH will arrange specimen transport from your facility to SHL.

C.  Initial Questions to Ask Healthcare Provider and Patient

Public health investigating suspect cases should ask about:

  1. symptoms (rash onset, rash characteristics, rash progression, other clinical findings cough, coryza, conjunctivitis and fever),
  2. measles immunization history,
  3. country of origin and length of residence in the US,
  4. recent history of travel (date and location of travel),
  5. recent out-of-town visitors (from where and visit dates), and
  6. recent contact with anyone with similar symptoms (who and date of contact).