PITTSBURGH (KDKA) — The superintendent of Frazier School District, William R. Henderson III, sent out a letter to parents and guardians yesterday informing them of a whooping cough case in the district.

A first grader was diagnosed with Pertussis, better known as whooping cough, according to the Pennsylvania Department of Health. The letter said that a number of students may have come into contact with the infected student.

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Pertussis is a highly contagious illness, spread airborne. It is also potentially fatal, mostly in infants under a year old.

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The letter said the state department of health advised that children expressing symptoms of whooping cough should see their doctor.

Pediatricians should be notified if a child has come into contact with someone infected if they are either around infants and/or someone pregnant or have pre-existing conditions that could be exacerbated by whooping cough. Doctors can give children an antibiotic to lower chances of getting ill, and they will be able to attend school while taking the antibiotic.

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The Pennsylvania Department of Health can be reached for questions about whooping cough at 1-877-PA-HEALTH.