My 3 year old daughter has got whooping cough, despite being vaccinated against it. She's been given clarithromycin. In worried about my 6 month old baby catching it. She's also been vaccinated but that hasn't made any difference to my older one. Does anyone have any experience of whooping cough in vaccinated kids- do they get a milder version of it? Is it pointless hoping that my baby won't catch it? How long does it go one for....? Thanks