The Delaware Division of Public Health (DPH) is issuing this Health Alert Network (HAN) update to notify health care professionals (HCPs) about considerations around accelerated measles vaccination in Delaware, given the current measles outbreak in Kent County.

Summary

On July 24, 2026, as part of the response to the ongoing outbreak, The Department of Insurance released updated guidance (https://insurance.delaware.gov/wp-content/uploads/sites/15/2026/07/domestic-foreign-insurers-bulletin-no167.pdf) requiring insurance providers to pay for early doses of accelerated measles, mumps, and rubella (MMR) vaccination for infants ages 6 through 11 months.

 

The Centers for Disease Control and Prevention (CDC) provides guidance for vaccination of specific groups against measles (https://www.cdc.gov/measles/hcp/vaccine-considerations/specific-groups.html). One such group is “groups at increased risks during an outbreak,” for whom health departments may provide additional recommendations. 

The measles outbreak in Delaware remains dynamic and continues to evolve. As of July 30, 2026, based on what is currently known about the outbreak, it is DPH’s recommendation that HCPs make decisions on accelerated vaccination of children on a case-by-case basis, using a shared clinical decision-making process with a patient’s parent/guardian. Additional information may arise as time goes on. If and when that happens, DPH will provide updated guidance.

DPH recommends that HCPs be on alert for cases of measles that meet CDC’s case definition (https://ndc.services.cdc.gov/case-definitions/measles-2013/). If an HCP has a high suspicion of measles, this should be discussed with the patient and a strong recommendation should be provided that the patient isolate until laboratory results or other confirmatory evidence is received. DPH also recommends that HCPs should use personal protective equipment (PPE), including respiratory protection (i.e., a respirator) that is at least as protective as a fit-tested, NIOSH-certified disposable N95 filtering facepiece respirator, regardless of presumptive evidence of immunity, upon entry to the room or care area of a patient with known or suspected measles.

Background

DPH is issuing this update in follow up to its prior health alert which was released on July 21, 2026: https://publichealthalerts.delaware.gov/delaware-health-alert-537-dph-confirms-first-positive-measles-case-in-over-a-decade/. This update provides additional information specific to early measles vaccination in select groups. 

 

Deciding Who Should Get Accelerated Vaccination

DPH recommends that in deciding whether to vaccinate a child early (outside of the routine MMR schedule), clinicians should utilize a shared decision-making approach.

This must take into account the child’s individual risk, based on the child and/or family’s known or probable exposure to measles. This includes exposure to individuals known to have measles or suspected to have measles, and based on the presence of people with signs and/or symptoms of measles in community settings with close interaction such as places of worship, vehicles, homes, etc. 

Within this context, accelerated vaccination includes both vaccination of persons aged 6 to 11 months as well as the provision of a second dose of MMR to children between 12 months and 4 years who previously received one dose only.

When a decision is made to give an accelerated dose of MMR, it is important to note the following:

  1. A minimum interval of 28 days must be maintained between doses, and
  2. Children who receive an MMR vaccine dose before their first birthday should still receive two MMR vaccine doses according to the routine schedule at 12 to 15 months and 4 to 6 years of age.

DPH epidemiologists and clinicians are available when needed to help providers determine what situations may or may not constitute an exposure. To contact one, call 302-744-4990 during regular business hours or email reportdisease@delaware.gov with subject line “Determining measles exposure.”

As the situation evolves, DPH will keep our provider community updated.

Clinical Characteristics

Health care professionals (HCPs) are recommended to:

  • Consider measles as a diagnosis in anyone with febrile illness and clinically compatible symptoms (e.g. rash, cough, coryza, or conjunctivitis) who has recently traveled abroad or to outbreak regions.
  • Immediately notify DPH about any suspected case of measles to ensure rapid testing and investigation. Contact the Office of Infectious Disease Epidemiology during regular business hours (302-744-4990) or the state’s 24-hour reporting line at 1-888-295-5156 outside of normal business hours.
  • Recommend MMR vaccine for patients who are unvaccinated or not fully vaccinated.
  • Do not allow patients with suspected measles to remain in the waiting room or other common areas of the health care facility; isolate patients with suspected measles immediately, ideally in a single-patient airborne infection isolation room (AIIR), if available. If an AIIR is not available, isolate patients in a single-patient room with a closed door.
  • Follow CDC’s testing recommendations and collect either a nasopharyngeal swab or urine specimen for Reverse Transcription Polymerase Chain Reaction (RT-PCR) as well as a blood specimen for serology from all patients with clinical features compatible with measles. RT-PCR is available at the Delaware Public Health Laboratory (DPHL) and through the APHL/CDC Vaccine Preventable Disease Reference Centers.
  • Ensure all patients are up to date on MMR vaccine and other recommended vaccines.
  • For people traveling abroad, CDC recommends that all U.S. residents older than 6 months be protected from measles and receive MMR vaccine, if needed, prior to departure.

If you suspect patient exposure, either administer MMR vaccine within 72 hours of initial measles exposure or immunoglobulin (IG) within six days of exposure. The MMR vaccine and IG provide post-exposure prophylaxis (PEP) to prevent measles or modify the clinical course of disease among susceptible people. For vaccine eligible people aged ≥12 months exposed to measles, administration of MMR vaccine is preferable to using IG, if administered within 72 hours of initial exposure. The following patient groups are at risk for severe disease and complications from measles and should receive IG: infants aged <12 months, pregnant women without evidence of measles immunity, and severely immunocompromised people. IG can be administered to other people who do not have evidence of measles immunity, but priority should be given to people exposed in settings with intense, prolonged, close contact (e.g., household, daycare, and classroom). Do not administer MMR vaccine and IG simultaneously, as this practice invalidates the vaccine.

Recommendations for Prevention

The best way to protect against measles is with the measles, mumps, and rubella (MMR) vaccine. MMR is safe and effective — serious reactions are extremely rare. Two doses of MMR vaccine are about 97% effective at preventing measles; one dose is about 93% effective. Talk to your patients about the MMR vaccine, especially if they are planning to travel. 

Laboratory Testing

Real-time RT-PCR (rRT-PCR): Nasopharyngeal swabs for PCR testing are preferred over urine specimens. PCR specimens can be requested to be tested at the Delaware Public Health Laboratory (DPHL). Contact the Office of Infectious Disease Epidemiology during regular business hours (302-744-4990) or the state’s 24-hour reporting line at 1-888-295-5156 outside of normal business hours to request approval for testing at the DPHL.

For serology, collect the first (acute phase) serum specimen (IgM and IgG) as soon as possible upon suspicion of measles disease. If the acute-phase serum specimen collected ≤3 days after rash onset is negative and the case has a negative result for real-time RT-PCR (rRT-PCR), or one was not done, a second serum specimen collected three to 10 days after symptom onset is recommended because the IgM response may not be detectable until 3 days after symptom onset. As of July 2026, serology testing is not currently available at DPHL, but DPHL may be able to facilitate testing through a partner, if needed.  

HCPs should use personal protective equipment (PPE), including respiratory protection (i.e., a respirator) that is at least as protective as a fit-tested, NIOSH-certified disposable N95 filtering facepiece respirator, regardless of presumptive evidence of immunity, upon entry to the room or care area of a patient with known or suspected measles.

DPHL offers nasopharyngeal PCR test for measles. Non-PCR testing is not available at the DPH Laboratory. Serology must be sent to a commercial laboratory. To order a nasopharyngeal PCR test for measles through the DPH Laboratory, an ordering Provider or Infection Preventionist must first contact the DPH Office of Infectious Disease Epidemiology for testing approval at 302-744-4990. Please also fill out the test requisition. Specimens not labeled on the tube, or without two unique identifiers (Name, date-of-birth) will be rejected. After the DPH Office of Infectious Disease Epidemiology approves, testing sample pickup is coordinated between the DPH Laboratory and DPH Office of Infectious Disease Epidemiology. Once sample reaches the laboratory, testing takes four to eight working hours. Processing time may change if the volume of tests continues to increase.

Reporting

Delaware physicians, laboratories, and other health care providers are required by regulations to report patients with measles to the Office of Infectious Disease Epidemiology (OIDE) immediately upon identification. Please do not wait for test results to be available to contact OIDE. Early reporting enables appropriate public health follow-up for your patients, helps identify outbreaks, and provides a better understanding of disease trends in Delaware. Cases can be reported to OIDE by calling 302-744-4990 (normal business hours) or 1-888-295-5156 (outside of normal business hours). Urgent notification by phone is preferred. You may also complete a Notifiable Disease Report PDF Form and fax the form to DPH at 302-622-4149 or email to:  reportdisease@delaware.gov. The form can be found online at: Reportable Diseases in Delaware – Delaware Health and Social Services – State of Delaware – Division of Public Health

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