Measles Outbreak in Clark County, WA (Vancouver / Portland Metro Area)

Posted Jan. 17, 2018. Past health advisories and alerts are archived for historical purposes and are not maintained or updated.

Clark County Exposure Sites

A measles outbreak is occurring in the Vancouver, WA/Portland, OR metropolitan area. As of January 16, 14 confirmed cases have been confirmed with additional suspect cases being tested. At least one confirmed case has been hospitalized. All cases are in children (12 cases are aged 10 and under). The initial case had a rash onset in late December. The most recent rash onset was January 13. The number of exposed individuals is expected to be in the thousands. A complete list of exposure sites for Vancouver and Portland is maintained here: clark.wa.gov/public-health/measles-investigation. At this time, we do not know whether any Spokane residents have been exposed.

Spokane Regional Health District (SRHD) asks that you consider measles in patients with the symptoms listed below and a history of travel in the 21 days prior to rash onset, particularly travel to the Vancouver, WA metropolitan area. A measles evaluation check list is attached to this advisory and is available on our website.

Symptoms & Incubation: 

Measles is characterized by a generalized maculopapular rash, fever, and one or more of the following: cough, coryza, or conjunctivitis. Measles has a distinct prodrome that begins with fever and malaise. Additional

symptoms can be conjunctivitis, coryza, cough, photophobia, and Koplik’s spots (which are pathognomonic but uncommonly observed). These spots are bluish-white specks on a rose-red background appearing on the buccal and labial mucosa usually opposite the molars. Temperatures may exceed 104⁰F, and usually fall two to three days after rash onset.  

The prodrome generally lasts two to four days before the rash occurs. The rash is maculopapular and begins on the head often along the hairline and spreads downward reaching the hands and feet. After about five days, the rash fades in the same order in which it appeared. Measles is highly contagious, can cause pneumonia and encephalitis, and can be fatal.  

Measles symptoms begin seven to 21 days after exposure and a person ill with measles is contagious for about four days before rash appears until four days afterward.  

More information on the clinical features of measles can be found here: cdc.gov/measles/hcp/index.html.

Vaccination Recommendations:

Most people in our state are immune to measles, so the public risk is low except for people who are unvaccinated, pregnant women, infants, and those with compromised immune systems. Children should be vaccinated with two doses of MMR vaccine, with the first dose between 12 and 15 months and the second at four to six years. Adults should have at least one measles vaccination. One dose of MMR is 93% effective at preventing measles; two doses is 97% effective. Those born prior to 1957 are considered immune. For more information, see cdc.gov/vaccines/vpd/mmr/public/index.html.

Evaluation of Persons with Suspected Measles:

Have patient enter through a separate entrance to the facility (e.g., dedicated isolation entrance), if available, to avoid the reception and registration area. If possible, the patient may also be scheduled at the end of the day to limit exposure to other patients/staff. 

  • Place the patient immediately in a negative pressure or airborne infection isolation room (AIIR).
  • If an AIIR is not available:
    • Provide a facemask (e.g., procedure or surgical mask) to the patient and place the patient immediately in an exam room with a closed door.
    • Instruct the patient to keep the facemask on while in the exam room, if possible, and to change the mask if it becomes wet.
  • Only staff with documented immunity to measles (two valid, documented doses of MMR vaccine or a positive IgG titer) should be allowed to be in the exam room with the patient.
  • PPE use:
    • Wear a fit-tested N-95 (or higher level) disposable respirator if available when caring for the patient; the respirator should be donned prior to room entry and removed after exiting room.
  • Instruct patient to wear a facemask when exiting the exam room, avoid coming into close contact with other patients, and practice respiratory hygiene and cough etiquette
  • Instruct patients suspected of having measles to isolate for four full days after the onset of the rash.

o    Once the patient leaves, the exam room should remain vacant for two hours before anyone enters. If staff must enter the room during this time, they are required to use respiratory protection. 

Laboratory Diagnosis of Measles: 

The diagnosis of measles can be made by isolation of measles virus from a clinical specimen. Urine and respiratory samples are both good clinical specimens for viral isolation. Measles virus isolation is most successful when samples are collected within three days of rash onset. However, virus may still be present in specimens seven days following rash onset. WA State Public Health Lab can perform expedited RT-PCR on nasopharyngeal and urine specimens of measles on suspect cases; pre-approval from Spokane Regional Health District is required prior to submission.

The laboratory diagnosis of measles can also be made by detection of measles IgM antibody in a single serum specimen. Approximately 80% of measles cases in unvaccinated people have detectable IgM antibody by IgM capture EIA within 72 hours of rash onset. In most instances, a serum sample should be collected for measles IgM at the first clinical encounter. However, if a negative result is obtained from a specimen drawn less than 72 hours after rash onset, another specimen will be required. Additionally, persons vaccinated against measles may have a blunted or transient production of IgM; therefore, a negative IgM in vaccinated persons suspected of having measles should not be used to rule out the case. 

All specimens for suspect measles cases must go to Washington Public Health Laboratory (WAPHL) using the form found here: doh.wa.gov/Portals/1/Documents/5230/302-017-SerVirHIV.pdf. Please take care when coordinating with your clinical laboratory to ensure they forward the specimens appropriately, or significant delays will occur. Please do not send specimens to a commercial laboratory.  

SRHD Epidemiologists are available 24/7 for consultation on laboratory diagnosis of measles at 509-869-3133.

Suspected or confirmed cases of measles are immediately notifiable and should be reported to Spokane Regional Health District Epidemiology at 509-869-3133.