Texas public health officials on Tuesday reported an additional 20 measles cases in the ongoing outbreak, for a total of 561 measles cases reported in the past two and a half months.
Four percent of the total Texas cases — or less than 25 cases — are “actively infectious,” according to the latest update from the Texas Department of State Health Services.
The state has designated 10 counties as having active spread of the illness. Those counties are Cochran, Dallam, Dawson, Gaines, Garza, Lynn, Lamar, Lubbock, Terry and Yoakum.
The measles outbreak began in Gaines County in late January. It has now spread across 23 counties in Texas, plus the states of New Mexico and Oklahoma.
A total of 58 people in Texas have been hospitalized, according to official data. Two children in the state have died, both of them school-aged and unvaccinated.
As of Friday, New Mexico had reported 58 measles cases and Oklahoma had reported 12 measles cases.
Cases across the U.S.
There have been other, unrelated measles cases reported in the U.S. this year. The vast majority of the total cases, though, of the measles cases reported this year are connected to the outbreak that began in Gaines County.
The U.S. Centers for Disease Control and Prevention reported 712 confirmed measles cases across the country as of April 10.
On April 11, the three states involved in the West Texas outbreak reported a total of 611 cases. It’s not clear if all of those had been reported to the CDC as of its April 10 update.
Measles is a highly contagious virus that spreads mostly among unvaccinated people. The two-dose measles-mumps-rubella vaccine is 97% effective at preventing illness.
Before a vaccine became available in the 1960s, nearly everyone in the U.S. contracted the virus by their teenage years.
In the decade before the vaccine became available in the U.S., millions of people were infected with measles each year, an estimated 48,000 people were hospitalized each year and an estimated 400 to 500 people died each year, according to the CDC.
Due to widespread vaccination, measles was declared eliminated in the U.S. in 2000.
Since then, there have continued to be outbreaks in communities with low vaccination rates. Public health experts have said that, if an outbreak last for longer than a year, the U.S. would lose its elimination status.
The current outbreak that began in West Texas could be a threat to that elimination status.
The best defense against measles is the vaccine. The vaccine is recommended for nearly everyone, beginning at about 12 months of age. The vaccine is not recommended for people who are pregnant or immunocompromised.
