Valley chickenpox rates static even as Texas cases jump

Although the number of chicken pox cases in Texas spiked sharply two years ago, rates in the Rio Grande Valley have only fluctuated slightly.

The Texas Department of State Health Services reports that the combined number of chicken pox cases in the four Valley counties dropped 14 percent from 2004 to 2005, then increased 8 percent from 2005 to 2006.

Almost 800 cases were reported in 2006, the latest local data available from the state.

These changes are small compared to the large fluctuations in statewide cases of chicken pox, known medically as varicella. In Texas, the number of chickenpox cases increased by 41 percent from 2005 to 2006, despite a requirement that all children be vaccinated against the disease before they enter kindergarten.

However, the number of cases dropped 21 percent from 2006 to 2007, contrary to recent media reports, said Doug McBride, spokesman for the state’s health department.

Locally, chicken pox rates have stayed fairly constant, said Dr. Brian Smith, regional director for Texas Department of State Health Services’ Region 11, which includes the Valley. A slight drop three years ago occurred because more children were getting the vaccine, and the later increase occurred because one dose of the vaccine didn’t fully protect them, he said.

“When we started using the vaccine, it wasn’t known that two doses were needed,” Smith said. “So we started seeing an increase (in chicken pox) in people who had received only one dose.”

Since the 2000-2001 school year, Texas has required that children receive one dose of varicella vaccine before starting school, but the state hasn’t yet mandated that children receive a booster.

In 2006, the Advisory Committee on Immunization Practices recommended that children receive two doses of the vaccine — one at ages 12 to 15 months and another at age 4 to 6 years.

Children who receive one dose of the vaccine can still get chickenpox, but the illness is less severe, Smith said.

Many reported cases of chicken pox in the Valley seem to be “breakthrough” cases, meaning the child had one vaccine dose but still got sick, said Danyta Delagall, epidemiologist for the Hidalgo County Health Department. As more Valley children receive the second dose, the number of cases is likely to decrease, Delagall said.

The varicella vaccine is provided under the state’s Vaccines for Children program, meaning that most low-income children can receive it for free, officials said. Many doctor’s offices and clinics offer the vaccine, they said.

Local health departments said they have plenty of the vaccine in stock and have never experienced a shortage.

Although chickenpox is not generally considered a serious illness, some children develop complications. The vaccine’s availability has cut down on those complications, said Herb Tolentino, director of nursing for the Cameron County Department of Health and Human Services.

“In the past, we would have a couple of deaths each year (from varicella),” he said. “That hasn’t happened since we started offering the vaccine.”

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Melissa McEver covers health and environment issues for Valley Freedom Newspapers. She is based in Harlingen and you can reach her at (956) 430-6252.