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Children with pertussis have decreased ability to cough up respiratory secretions and develop thick, glue-like mucus in the windpipe. This causes severe coughing spells that make it difficult for them to eat, drink, or breathe. The child may suffer from coughing spells for two to three weeks or longer. Sometimes the child coughs several times before breathing in; when the child finally does breathe in there is often a loud gasp or “whooping” sound. The disease is most severe when it occurs early in life; it often requires hospitalization.