Dr Spur's mystery case : the case of the chicken or is it the egg?

Abstract

Re: Advice on recurrent airway infections in a three-year-old patient. I am writing to ask your advice on Michael, a three-year-old patient, whose mother is concerned about the possibility of an underlying immune deficiency. She reports that he is frequently unwell, presenting with airway infections almost every month since she discontinued breastfeeding him at nine months so that she could return to work. He started attending daycare at that point.