Health officials say the number of whooping cough cases in Lake County has already surpassed last year's total.
The Lake County Health Department reported Friday that there have been 178 whooping cough cases so far this year. Last year, there were 175 cases.
The Health Department is urging adolescents and adults to receive a booster shot for additional protection against this illness, which is also called pertussis.
Whooping cough is highly contagious and can last for several months.
Symptoms include a long-lasting, severe cough that's usually worse at night. Officials say people who have such symptoms should see a doctor, because over-the-counter medicines don't work.
Illinois now requires children entering sixth and ninth grades to show proof of having a Tdap (TEE'-dap) booster in order to attend school.
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