Health Alert: Measles Outbreak in Montgomery County, Texas

Summary

The Texas Department of State Health Services (DSHS) is reporting an outbreak of measles in Montgomery County. Last week, four cases were confirmed in unvaccinated residents of Montgomery County following exposure to a person with measles who traveled to Texas from another state.

Due to the highly contagious nature of this disease, additional cases may occur. DSHS advises clinicians to follow the measles immunization recommendations below and immediately report any suspected cases to the local health department, preferably while the patient is in their presence. Members of the public can protect themselves by ensuring they have been vaccinated against measles.

Background

The week of July 20, 2026, the Montgomery County Public Health District reported four cases of measles among Montgomery County residents associated with exposure to a person with measles who traveled from out of state. These cases prompted a local Health Alert on July 23.

Measles is a highly contagious respiratory illness. The virus is transmitted by infectious respiratory droplets or airborne spread when an infected person breathes, coughs, or sneezes. Measles virus can remain infectious in the air for up to two hours after an infected person leaves an area. Illness onset (high fever, cough, runny nose, and red, watery eyes) begins 7 to 21 days after someone is exposed. A few days later, the telltale rash breaks out as flat, red spots on the face and then typically spreads down the neck and trunk to the rest of the body. A person is contagious about four days before the rash appears to four days after. People with measles should stay home during that period.

The best way to prevent getting measles is to be immunized with two doses of a vaccine protecting against measles, which is primarily administered as the combination measles-mumps-rubella (MMR) vaccine. DSHS and Centers for Disease Control and Prevention (CDC) Advisory Committee on Immunization Practices (ACIP) recommend children receive one dose of MMR vaccine at 12 to 15 months of age and another at 4 to 6 years. Two doses of the MMR vaccine are highly effective at preventing measles. Some vaccinated people can occasionally develop measles; however, they generally experience milder symptoms and are less likely to spread the disease to other people. Children too young to be vaccinated are more likely to get infected and more likely to have severe complications if they do get sick.

Recommendations for Health Care Professionals:

Healthcare providers should consider measles in patients presenting with the following symptoms:

• Fever ≥101°F (38.3°C) AND
• Generalized maculopapular rash lasting ≥3 days that typically begins at the hairline/scalp and progresses down the body AND
• Cough, runny nose, or conjunctivitis OR Koplik spots (bluish-white specks on a red-rose background appearing on the buccal and labial mucosa usually opposite the molars).

Immediately isolate anyone with suspected measles. If possible, isolate the person in a negative air pressure room.

Immediately report any suspected measles cases to your local health department (contacts by county at Disease Reporting Contacts). If possible, please report while the patient is present to facilitate testing and the public health investigation, including follow-up of potential exposures.

Diagnostic Testing

Testing for measles should be done for all suspected measles cases at the time of the initial medical visit:

https://www.dshs.texas.gov/idps-investigation-forms/disease-reporting-contacts

• DSHS strongly encourages providers to submit specimens for PCR testing to the DSHS Laboratory because genotyping will be performed on positive PCR specimens, which can help link cases during outbreaks.
• The DSHS Laboratory can perform PCR testing on throat swabs (preferred) or nasopharyngeal swabs placed in viral transport media and serology on serum specimens.
• Measles PCR and serology (IgM and IgG) testing is available at both the DSHS Laboratory and at commercial laboratories.
• Providers should work with their local health department or DSHS regional office to coordinate testing to ensure specimens are submitted correctly and meet testing requirements.
• Unless coordinated in advance, specimens may only be received by the DSHS Laboratory during normal business hours Monday through Friday.

Recommendations for Prophylaxis

• Post-Exposure Prophylaxis (PEP)
  • MMR vaccine, if administered within 72 hours of initial measles exposure, may provide some protection, or modify the clinical course of disease among susceptible persons who otherwise have no contraindications to MMR vaccination (e.g., severe immunocompromise, age <6 months, pregnancy). (CDC: Measles). Providing MMR vaccine within 72 hours should be focused on people unvaccinated and people with one dose of MMR vaccine.
  • Susceptible persons who receive a dose of MMR vaccine as PEP within 72 hours of initial measles exposure may return to childcare, school, or work.
  • For people who are fully vaccinated, with two doses of MMR vaccine or have measles infection documentation, an additional dose of MMR vaccine is not recommended.
• Immune globulin (IG)
  • IG, if administered within six days of initial measles exposure, may provide some protection against measles or modify the clinical course of disease among susceptible persons (CDC: Measles).
  • IG is the only option for PEP for populations which cannot receive MMR (infants less than six months of age, severely immunocompromised people, and pregnant women).
  • Priority should be given to persons exposed in settings with intense, prolonged, and close contact (e.g., household, daycare, classroom) and for those at high risk of severe disease. IG PEP should be provided to severely immunocompromised contacts regardless of prior measles vaccination status due to the risk for severe disease.
  • IG PEP can be given to susceptible infants aged 6-12 months, although MMR vaccine is preferred per American Academy of Pediatrics (AAP) guidance if received within 72 hours of exposure.

Recommendations for the Public

Measles is extremely contagious and can cause illness and sometimes life-threatening complications to anyone who is not protected against the virus. If you think you have measles or have been exposed to someone with measles, isolate yourself from others. Before arriving at a healthcare facility, call and inform the facility of your symptoms and recent measles exposure so they can prepare for your arrival without exposing other people to the virus. Review your and your child's vaccination history to see if you are up to date on your measles vaccines. Additionally, discuss with your provider your vaccination history and any questions about these vaccines.

People with confirmed or suspected measles should stay home for four full days after rash onset. During an outbreak, people without documented immunity through vaccination or a history of previous measles infection should avoid anyone with measles to protect themselves and help prevent the spread of measles in the community.

Recommendations for Parents of School-aged Children

Back-to-school means a long to-do list in a short time, including annual health checks with your child's pediatrician and receiving immunizations needed for school entry and according to immunization schedules.

• To get vaccinated, people can go to their health care provider or a pharmacy.
• Vaccines are also available through the Texas Vaccines for Children (TVFC) and Adult Safety Net (ASN) Programs.
• To review eligibility, enrollment, cost, and locations of a TVFC or ASN provider, visit the DSHS Immunization Program's Frequently Asked Questions webpage.
• Pharmacists may vaccinate children aged 13 years and under with a prescription from their doctor. They can vaccinate children 14 and up without a prescription.
• Students with measles must be excluded from school for 4 full days after rash onset. Additional information on school exclusion and readmission can be found at School Communicable Disease Chart.
• According to the Texas Administrative Code (TAC) Rule §97.7, schools and childcare settings shall exclude unimmunized children for at least 21 days after the last date the unimmunized child was exposed to a measles case.

For More Information:

• For Healthcare Professionals - Clinical Overview of Measles
• Acceptable Presumptive Evidence of Immunity to Measles | MMWR
• Measles Vaccination | Measles (Rubeola) | CDC
• Laboratory Testing for Measles | CDC
• CDC Measles Resources
• DSHS Measles Information
• DSHS Immunization Program - Frequently Asked Questions
• DSHS Immunization Program - Information for Parents