Simba allergic to our fall and winter?

I seem to have a little Simba that have a problem with our falls and winters here (where we are). He never gets sick in the spring or summer (so far for 15 ½ years), but display a pattern when it comes to the fall and winter confused_cat ?

Here is his "stats"

2000-08-29 - Gastritis, to ER (but I really believe it was pancreatitis), 4 yrs old

2002-07-31 - Gastritis, to ER (same thought as above), 6 yrs old

2006-10-28 - Diabetes, to ER, 10 yrs old

2007-10-05 - Pancreatitis, fPLI 343,1, to ER, 11 yrs old

2008-09-07 - Pancreatitis fPLI 129, to ER, 12 yrs old

2010-01-08 - Strange seizure, to ER, 14 ½ yrs old

2010-01-18 - Pancreatitis, to ER, 14 ½ yrs old

2011-09-14 - Vomitted with little blood in, Flagyl, 15 yrs old

2011-10-07 - Blood in the stool, 15 yrs old

2011-11-05 - Same strange seizure as above, 15 ½ yrs old.



Are there other cats that gets sick/more sick when the fall and winter comes?

 

Could he have allergies to fall pollens & molds which lower his resistance to other things?

 

I don't know, BJM, but it is truly enigmatic and a mystery that it all seems to happen during the fall and winter. I will take him to the hospital but doubt they have any clues. But imagine if I hadn't been at home that day in fall 1996 and seen this little homeless approx 6 months baby boy in the streets outside my apartment. Perhaps it is trauma in the nerve system and body still and he has Post Traumatic Stress Syndrom, manifesting itself in the body in various forms.