BOULDER, Colo. (CBS4) – The Boulder County Health Department provided more information about an ongoing Pertussis outbreak, also known as whooping cough. They say there have been 78 cases so far this year.

Boulder High School

Boulder High School (credit: CBS)

Officials tell CBS4 May had the highest number of cases at 23. They add the last epidemics in their area happened in 2013 (230 cases) and 2012 (170 cases).

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They warned of an outbreak at Boulder High School, but say five schools have at least one case.

Symptoms usually develop 7-10 days after exposure and include a runny nose, sore throat and severe coughing.  Someone with pertussis may look and feel fine between coughing episodes and may not have a fever.

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The virus is contagious until the patient has had five days of antibiotics. They are contagious for three weeks if not treated.

Pertussis is commonly included in the routine “tetanus booster” vaccination.

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LINK: Boulder County Pertussis Information