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The Idaho Department of Health and Welfare is reporting an abnormal increase in cases of a highly contagious bacterial infection that is targeting infants in the southwestern portion of the state.

Pertussis, also known as whooping cough, has sickened more than 120 people in southwest Idaho, according to an update shared today on the department's Facebook page. The infection is highly contagious, with runny nose, persistent coughing and fever being the major symptoms.

Canyon County has reported over 90 cases alone, with July being the worst month so far. The health department is urging parents to get their children vaccinated sooner than later, as it takes several months for the vaccine to become effective.

There have been over 250 cases statewide so far in 2018, compared to 32 for all of 2017.