WASHINGTON — The official leading the Centers for Disease Control and Prevention’s response to the West Texas measles outbreak said the number of confirmed cases is likely under-reported. This, as the highly contagious virus continues to spread, with more than two dozen new cases reported this past week in Texas alone. 

If you ask U.S. Health and Human Services Sec. Robert F. Kennedy, the growth rate for news measles cases is flattening.

“Our numbers in this country have now plateaued,” Kennedy said earlier this month.

So far, 800 cases have been reported in the U.S. this year. But some public health experts say the full scope of the outbreak still is not yet known.

“There’s no basis to say that this is plateauing, because what we know is that the number of cases that are reported probably don’t represent the full extent of the outbreak,” Dr. Amesh Adalja, a senior scholar at Johns Hopkins Center for Health Security, said.

“We’re still seeing ongoing transmission. There may be lines of transmission that are not even coming to light because they’re not presenting for diagnostic testing. They’re not presenting for care. So I don’t think we have a real idea of how big this might be,” Adalja continued.

In a meeting of the Centers for Disease Control and Prevention vaccine advisory committee, the senior scientist leading the CDC’s measles response said there are likely a large number of cases not being reported.

“In talking with families, they may mention prior cases that have recovered and never received testing, other families that may have cases and never had sought treatment. So we do think that there is under testing and therefore under diagnosis,” said Dr. David Sugerman of the CDC.  

Sugerman acknowledged the transmission is driven by close-knit, under-vaccinated communities.

Public health experts say historically, two or three deaths may occur for every 1,000 reported measles cases.

This year, two school-aged children have died in Texas, as well as an adult in New Mexico.  

“There’s a concern that when you don’t have full capture of the cases occurring, that transmission chains are going to land on people who eventually are going to end up in the hospital or end up with serious consequences, and the longer we don’t have control of the outbreak, the longer it’s going to spread, the more likely we are to see severe cases,” Adalja said.

To help get the measles outbreak under control, the CDC has deployed response teams to West Texas. It has also made additional doses of the measles-mumps-rubella vaccine available to local health departments.

Sugerman said it could cost $30,000 to $50,000 in public health spending to respond to each case.

“We are scraping to find the resources and personnel needed to provide support to Texas and other jurisdictions,” he said.

Prior to the deaths this year, the U.S. had not seen a measles fatality in a decade.