The Texas measles outbreak that began in Gaines County has grown to 683 cases, officials said on Friday. Ten of the impacted counties in Texas have “ongoing measles transmission,” although the state public health department estimates there are currently fewer than 10 confirmed cases still infectious.

The new cases in an unvaccinated adult and child come amid a statewide outbreak that has sickened almost 700 people since January, according to the Texas Department of State Health Services.