Thanks for posting your query here. I can appreciate that you are worried about your result showing heavy mixed respiratory flora. I can reassure that this is not dangerous. We all carry lots of bacteria and viruses in our body, on skin, in nose, throat and gut. They are symbiotic - living with us but not causing any medical problems to us unless we have very weak immunity. Mixed respiratory flora usually means they have identified some bacterias, however they are also known to be carried by healthy individuals. I would visit the doctor again since you have a cough ongoing for a period of 4 weeks, longer than most other conditions causing cough. It could be allergy. Do you get infections easily? Have you had any travel/visit recently abroad or tropical area? Apart from feeling fatigued, are there any other symptoms? Do you smoke? Your doctor may wish to get a chest x-ray, after clinical examination. I hope I have been helpful to guide you further. Regards Dr Tejas Shah