below is a list of both common and often seen diseases the we all get.
This diseases is caused by often other diseases like Epstien-Barr Virus (EBV), or outer things such as salt cured fish high on nitrosamines and so forth. the syptoms of Nasopharynx Cancer are few at fisrt then get pretty bad, mostly tumors, once the tumor has expanded from its site of origin in the lateral wall of the nasopharynx, it may obstruct the nasal passages and cause nasal discharge or nosebleed. Obstruction of the auditory tubes may cause chronic ear infections, and patients may experience refferd pain to the ear. the one thing that make this an incredably bad diseaes is the infected cells "leaks" into other areas of the body.
Asthma is probably the most common disease for the Respretory System. The thing that makes asthma so bad is that people with the disease often have attacks wich the airways constrict, become inflamed, and is lined with exesive mucus. The causes for asthma let alone asthma attacks are so large that no one has the atentionspan to read all of them so well leave it at enviermental, genetic ,and Gene-environment Interactions. Asthma also has the negative feature of weezing, shortness of breath, chest tightness, and cough. asthma, even today, has no cure and the only way to avoid attakcs is to avoid causes for them like smoke, and car exausts.
The RSV is a very, very, VERY common disease found in people of all ages. The symptoms of RSV are almost exactly like the common cold, the only diffrence is that RSV causes the Oropharynx to swell up, and its even more contagious. But like the common cold we don't have a cure of it but wait it out and hope you don't recatch it.(It is possible with this disease) other wise you should look at the common cold for other information.
Bacterial Pneumonia is the infection of the lungs by bacterium. There isn't any symptoms known other than lak of energy. The treatments however differ based on wich organisum it is (Gram possitives and negatives) and all are diffrent types of anti bactreal substance (no two bacteria is alike, and in your lungs, requiring diffrent treatments)
Lung cancer is the single worst killer among all the cancers known . It involves the mutation of cells in the lungs and lung passage ways to grow ,and grow ,and grow with no end making "tumors" these tumors block out air and stop the functioning of all cells near by it, and just like Nasopharynx Cancer, it "leaks" into other parts of the body making other cancers and tumors. Lung cancer is diagnosed depending on how the infected cells look. today theres only small cell lung cancer and non-small cell lung cancer, each with diffrent treatments. the really sure fire way to get lung cancer is by SMOKING! Other wise its the sterio-typical radiation causes for nearly all cancers known.