LANSING, Mich. (Michigan News Source) – Health leaders in Michigan are on “high alert” as immunization rates among toddlers for the primary childhood vaccine series fell yet again in June to 67.1%.

The vaccines in that series include polio, measles, tetanus, whooping cough, hepatitis and pneumonia.

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The rates show a dip of about 6.9 percentage points since July 2019, and it leaves roughly one-third of Michigan children vulnerable to one or more vaccine-preventable diseases, according to new data released Thursday from the Michigan Care Improvement Registry.