About 80 more measles cases have been confirmed over the past week, bringing the total for an Ohio outbreak to about 240 cases across six counties.
Ohio's Department of Health reports Knox County has 143 cases of the highly contagious respiratory illness. Six of those involved hospitalizations.
Neighboring Ashland County has 36 cases, and Holmes County has 33. Residents of Coshocton, Richland and Wayne counties also have been infected.
Health officials say the outbreak started among Amish who had traveled to the Philippines, which has had a measles epidemic.
Measles is caused by a virus. Symptoms include fevers, coughs, rashes and pink eye.
Officials encourage vaccination to limit the spread of measles and of mumps, which has caused a separate outbreak in central Ohio. That outbreak has over 400 cases.