Everything we know about the measles outbreak's 'patient zero'

Dr. Christ says with little exception for individuals who can't get vaccinated, vaccinations are key to preventing and outbreak of infectious diseases like measles.

As they bring awareness locally to the community, Espinoza said, her public health counterparts in southeast Texas are trying to pinpoint the reason behind the cases there.

Galveston County Health District also confirmed a case involving a boy whose age ranges from 12 to 24 months old, according to KTRK-TV in Houston. An additional case was confirmed in King County, which includes Seattle, and in Multnomah County, Oregon, which includes Portland and lies across the Columbia River from Clark County. The outbreak in Clark County has been concentrated mostly among unvaccinated children.

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"We know there's a link between two of the Houston-area cases, and public health is investigating to determine whether the others are linked or whether they occurred independently", Texas Department of State Health Services spokesman Chris Van Deusen said.

"While this is a relatively small number of cases, it's a good time to make sure you and your children have gotten the recommended two doses of measles vaccine", Van Deusen said.

According to the Centers for Disease Control and Prevention (CDC), there were 349 cases of measles in the U.S.in all of 2018, whereas the European Centre for Disease Prevention and Control reported that in just the month of November 2018, there were 385 cases reported in 16 countries in the European Union. If anyone suspects that they or their child has symptoms of measles, they are urged to call their GP first before visiting. Forty-two patients were not immunized against the virus, while health officials had not verified the immunization status of six patients.

Espinoza said the measles, mumps, and rubella vaccine, or MMR vaccine, is 97 percent effective.

The health department is encouraging anyone who may have symptoms of measles to contact your doctor.