All the elderly cases of pneumonia I hear about are during winter and 'flu/cold season, or in spring in the height of hayfever.
That's a good illustration of the dangers of going by assumptions and impressions. Our impressions of what we've heard or seen are often wrong, especially if it's our impression of something we weren't especially focused on at the time so weren't making any type of careful and systematic study.
I'm not particularly knowledgeable about pneumonia either. I haven't known that many people who had it (as far as I was aware) so have very little personal knowledge of what times of year one is most likely or unlikely to get it.
So when I read your post I got curious and looked it up. Here's what a quick search of summer pneumonia turned up:
Walking pneumonia is a non-medical term to describe a mild case of pneumonia. It can also be called atypical pneumonia because the disease is different from more serious cases of pneumonia caused by typical bacteria...
Lots of things can cause pneumonia, including:
Bacteria, including mycoplasma
Viruses
Fungi
Other infectious agents
Chemicals
Inhaled food
...
People who have walking pneumonia are seldom confined to bed or need to be hospitalized. Some may even feel well enough go to work and carry on with other regular routines, just as they might with a cold...
Anyone at any age can get walking pneumonia...
People who live and work in crowded places, such as schools, homeless shelters, and prisons have a higher risk of contracting the disease...
Cases of walking pneumonia are most common in the late summer and fall.
