A cough is generally a result of an irritant such as stomach acid
(gastric reflux), mucus (asthma), hair spray, perfume, dust, pollen, mold, even spicy food, post nasal drip, or infection. It could also be due to infection such as pneumonia or bronchitis. Chronic sore throats can be allergic, viral or bacterial in origin. Many viral conditions like EBV (glandular fever) behave in this way with recurrent respiratory infections.