HARRIS COUNTY, Texas — A fourth measles case in Harris County has been confirmed, according to the Harris County Health Department.

The department said the patient, age 15 to 24 years old, was not vaccinated for measles and is from southeast Harris County.

The latest case brings the total number of persons with measles in the Houston area to six. That total includes four in Harris County, one in Montgomery County and one in Galveston County.

The latest Harris County case could be part of a pattern to come as measles has a two-week incubation period.

“So that says to me that maybe we are seeing the second wave of this measles outbreak,” explained Dr. Peter Hotez, professor of pediatrics and a dean of the National School of Tropical Medicine at Baylor College of Medicine. “People tend to blow it off as kind of a rash or a benign illness...but I have a very different take as a vaccine scientist and pediatrician. In 1980s, 1990s, measles was the single-leading killer of children globally.”

The measles virus spreads quickly and is especially dangerous for those who are unvaccinated.

Infants carry some of their mother’s immunity up until 6 months old, so they are partially protected. The first vaccine isn’t offered until 12 months of age, putting babies between 6 to 12 months old at high risk of contracting measles.

“It is the single-most contagious virus we know about," Dr. Hotez said. "If you are a parent now with an infant, especially between the ages of 6 months and 12 months, you have to be concerned about bringing your baby out into public spaces. Unfortunately, Texas had the single largest number of kids not getting vaccinated of any state in the country.”

About 60,000 kids aren’t vaccinated in Texas which does not include the roughly 300,000 home-schooled children who are required to report whether they have vaccines.

“We are clearly pressing our luck and it’s only a matter of time until the big one comes...the big measles outbreak," Dr. Hotez said.

Earlier this month, health officials said four of the patients are children under the age of 2. The other is a Harris County woman who is approximately 30 years old.

The 1-year-old girl in Montgomery County is connected to one of the Harris County patients. We don't know which patient or how they are connected.

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At least three of the children had received the first dose of the MMR (measles, mumps and rubella) vaccine, but aren't old enough to receive the second dose. 

Measles is highly contagious, and if one person has it, 9 out of 10 people around that person will also become infected if they’re not yet vaccinated. About 1 out of 4 people who get measles will be hospitalized.

"It takes 2-3 weeks for the full incubation period. If we start to see more cases then, I think we have some real concerns." said Dr. Philip Keiser, an Infectious Disease Specialist with the Galveston County Local Health Authority.

He says the toddler in Galveston County who contracted measles had received the first dose of the vaccine, but is too young to receive the second, which is recommended starting at 4 years old.

Dr. Keiser says everyone should be vaccinated against the highly contagious air-borne illness.

"Over someone's life-time, it's 97 percent effective. 3 percent failure rate, so it's pretty good odds." said Dr. Keiser.

Measles is caused by a virus which spreads to others through coughing and sneezing.

“However, it is easily preventable. Parents and caregivers have the power to protect their children and themselves from this disease by getting vaccinated,” said Umair A. Shah, MD, MPH, Executive Director for HCPH.

Measles can be dangerous, especially for babies and young children. Measles is an airborne virus that lives in the nose and throat mucus of an infected person. It can spread to others through coughing and sneezing. Symptoms of measles are a high fever, runny nose, cough, red-watery eyes and sore throat that is followed by a rash breakout 3-5 days after symptoms begin.

Measles is prevented through the combination MMR vaccine.

The Centers for Disease Control and Prevention (CDC) recommends that children get two doses in order to be fully protected:

  • The first dose at 12 through 15 months of age
  • The second dose at 4 through 6 years of age

The best way to protect yourself and your family against measles and other vaccine-preventable  diseases is by immunization. HCPH encourages individuals to contact their health care provider if they show signs and symptoms of measles. 

For a list of recommended vaccines, please visit the Centers for Disease Control and Prevention or speak to your health care provider.

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