Arizona’s largest measles outbreak in three decades continues to grow.
Arizona has now confirmed 223 measles cases since the current outbreak began, but Arizona Department of Health Services officials say that's likely an undercount.
Most of the state’s current outbreak has been in Mohave County around the small Utah-border town of Colorado City. According to the Department of Health Services, that area has had a steady stream of new cases each week since mid-August.
Coconino and Pima Counties also recently confirmed their first measles cases. Navajo County had reported four measles cases last June.
Dr. Joel Terriquez, ADHS Bureau of Infectious Disease medical director, said Arizona’s outbreak may not end anytime soon.
“When this infection is affecting a community that may not have optimal vaccination rates, we’re going to see the number of cases spreading,” Terriquez said during a call with reporters Tuesday.
Colorado City is a town of about 2,500 people. Many residents of the area are members of the Mormon-offshoot polygamist sect known as FLDS. The community has very low vaccination rates.
One Colorado City elementary school last year reported a kindergarten MMR vaccination rate of just 7% – the lowest rate reported by any school in the state, records from the state Department of Health Services show. The other school in the town reported a 40% kindergarten MMR vaccination rate last year.
Terriquez said vaccination is the best protection against the extremely contagious virus, and 97% of the state’s cases have been among people who are unvaccinated.
“The way for us to stop this would be for us to continue promoting vaccination,” Terriquez said.
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