The Clinton campaign is definitely hiding something and trying to do some major damage control. There have been numerous videos surfacing of her strange symptoms over the last few months. It looks like something neurological, and definitely not just like pneumonia. They are hiding something big, and voters deserve to know that truth.
Pneumonia is a lung infection that can lead to diffferent types of cancer. If diagnosed, it is recommended to retire from any self-involved activities. Indeed, the danger is to spread infection to another person, even if contagion has not been clearly demonstrated in case of pneumonia. Clinton has to be healed prior to run for the office.
Clinton's diagnosis may be no more than it is. I personally think that this health issue is being blown up by the media on purpose to arouse speculations on Clinton being fit for the post. There has been no health issue up till now and it is likely due to stress.
Hillary Clinton and her campaign are not hiding a more serious illness from the public. She was diagnosed with pneumonia by a doctor. It fits with her previous symptoms, such as when she had a coughing fit a couple of weeks ago. Other medical professionals agree with the diagnosis. She looked fine a couple of hours later.