Hello Dr Sumit, I m a male, 30 years, 6 4 , 169 pounds. I m an amateur long distance runner and a cyclist and follow a regular exercise regimen. I m very susceptible to sore throat and even if one drop of cold fluid touches my throat I develop laryngitis . How can I develop immunity against cold, cough and flu? I m desperate to get rid of frequent bouts of cold and cough once and for all. -- Take care, Ratan