HOUSTON — Texas health officials have confirmed another case of measles in Denton County, bringing the total number statewide to seven. 

We’ve also learned the five Houston-area victims might be connected. An 18-month-old Galveston boy may be linked to three Harris County cases: Two toddlers and a woman between 25 and 35 years old. 

The Galveston toddler has relatives in Houston and spends a lot of time here. He had the first dose of the MMR vaccine but he's too young for the second. 

The 1-year-old girl in Montgomery County is also connected to at least one of the Harris County patients. 

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. 

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Health officials attribute recent cases around the country  to the growing number of parents in the anti-vaccination movement..

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

Doctors are also advising schools, day care centers and healthcare workers  to be on the out for possible symptoms, which include fever and rash.