Parents are being warned about a case of pertussis – or whooping cough – at a Greater Victoria school.

Claremont Secondary School in Cordova Bay emailed parents Wednesday alerting them that children may have come into contact with the pertussis germ, which is spread by coughing.

The illness begins with children developing a persistent cough, which can be followed by gagging or vomiting.

It can have serious consequences for young children, especially those under one year old.

Anyone who suspects their child may have pertussis is asked to contact their family doctor immediately.

Island Health said it's informed 15 schools about cases of whooping cough since the start of the school year, including two so far in 2018.

For more information on pertussis symptoms and treatments, visit HealthLink BC's website.