Measles case confirmed in Santa Clara County with public exposures

A case of measles with rash onset on May 25, 2025 has been confirmed in Santa Clara County. This is the first confirmed measles case reported in Santa Clara County since 2019 and the 12th case in California in 2025. The person tested positive after returning from international travel. The person was not hospitalized and is now isolating at home. Contact tracing to date has identified potential exposures at private locations including healthcare facilities where the individual sought care and testing, and several public locations detailed here. At this time, no further cases have been reported.

Recommendations for Healthcare Providers

1. Refer exposed individuals who are unvaccinated to Public Health. 

Individuals exposed at the locations above who are unvaccinated, pregnant, a parent of an infant, or immunocompromised have been directed to contact their healthcare provider immediately as they may require post exposure prophylaxis. Please contact the Public Health Department for additional guidance for exposed individuals who fall into one of these categories as they may also need to quarantine. Public Health can be reached by calling (408) 885-4214 and select option 3. After hours, call (408) 998-3438 and ask for the Health Officer on call.

2. Suspect measles in any patient with fever and rash.

High risk features include:

• Clinical symptoms consistent with measles including a prodrome of fever, malaise, and any of the “3 Cs” – cough, coryza (runny nose), or conjunctivitis followed by a maculopapular rash.
• Epidemiological risk factors for measles including any of the following:
  • International travel exposures including travel outside of North America, transit through U.S. international airports, or interaction with international visitors (including at U.S. tourist attractions) in the last 21 days.
  • Domestic travel to an area with known measles transmission in the last 21 days.
  • Known exposure to measles.

Ask about measles vaccination status, onset and duration of fever and rash, exposure to other persons with febrile rash illness, travel history, and contact with international visitors or visitors from areas with recent measles outbreaks in the three weeks prior to illness.

3. Mask and isolate any suspect measles case.

If you suspect measles in your patient, mask and isolate the patient immediately. Do not allow patients with suspected measles to remain in the waiting room or other common areas of the healthcare facility. Isolate patients in a single-patient airborne infection isolation room (AIIR) if available, or in a private room with a closed door until an AIIR is available.

Healthcare providers should be adequately vaccinated against measles and should adhere to standard and airborne precautions when evaluating suspect cases regardless of their vaccination status. All healthcare personnel entering the patient room, regardless of immune status, should use respiratory protection at least as effective as an N95 respirator per Cal/OSHA requirements. 

4. Report suspect measles cases immediately to Public Health.

Healthcare providers are required to notify the Public Health Department immediately via phone of any suspected case of measles. Call Public Health immediately, while the patient is still in your office, at (408) 885-4214 and select option 3. After hours, call (408) 998-3438 and ask for the Health Officer on call. Be prepared to provide (1) a detailed description of fever and rash onset and evolution, (2) a photo of the rash, and (3) complete vaccination and travel history.

5. Collect specimens for testing suspect measles cases.

Collect a throat swab and urine sample for measles PCR testing. Collect specimens in-office rather than sending the patient to a laboratory.

• Throat swab: Use a sterile synthetic swab. Place swab into viral or universal transport media.
• Urine sample: Collect 10-50 mL urine in a sterile container.

Storage and transport: Store all specimens at 4°C. Transport all specimens on cold pack within 24 to 72 hours.

6. Ensure suspect case isolates while awaiting testing results.

If discharged home: Provide patient with instructions to isolate at home until test results return. They may not attend work or school or otherwise leave their home except to obtain emergency medical care.

If transferred to a higher level of medical care: Directly inform EMS and the accepting facility so that appropriate precautions can be put in place.

Resources

1. County of Santa Clara: https://publichealthproviders.santaclaracounty.gov/health-care-providers/diseases/measles
2. California Department of Public Health (CDPH): https://www.cdph.ca.gov/Programs/CID/DCDC/Pages/Immunization/measles.aspx
3. Centers for Disease Control and Prevention (CDC): https://www.cdc.gov/measles/index.html