Hi Sheridan,
You asked two really important questions. But your second question might be important. It is true that severity of CF can vary according to mutation combinations and environment. I was perfectly normal until age 21, until I became horribly symptomatic. Increasing exacerbations with more frequent hospitalizations; Pseudomonas, staph, bronchectasis, MAC, etc. with declining lung function, reaching as low as Fev1 32%. Plus almost total drug resistance. Typical C.F manifestations. So I know where you are coming from.
My condition changed when I started going to a doctor that treated me in an entirely different manner. I haven't been on IV meds in 11 years (knock wood!) My last several cultures aren't even picking up anything - which means the bacteria is reduced at any rate. My Fev1 started going steadily back up. And drug sensitivities returned, by being off antibiotics.
So here is what I've learned from my doctor. You can take whatever advice you see fit for you: Living in a hot, humid climate is very detrimental for respiratory patients. These climates have high levels of molds and funguses, and allergies are more likely to be triggered. I have noticed that many people on this site start having much more serious problems when they move to these climates. They start having sinus issues, fungal infections like Aspergellis. I feel so bad when I see people start the endless cycle of IV meds, bronchs, sinus surgeries. I always wonder if I should pass this information along, but how can I tell people to move? But since you are asking...
The next thing is your home. You are worried about germs. Germs are everywhere. They live on us. Frequent handwashing helps. After an exposure to something a shower or a nasal rinse can help.
But the bigger problem is allergies and irritants. One of the reasons that people get recurrent exacerbations is because something or things are causing their airways to become inflamed. When the airways swell, they trap mucus that holds the bacteria with no way to get coughed out.
This is the asthma component of CF that is almost never addressed by doctors . Everyone is on asthma meds, but the doctors tell them asthma is not their probem. I heard this from more than one doctor...as I got worse and worse. So they'd say asthma wasn't my problem, yet they had nothing to offer me. The asthma component of CF due to inflammation is the part of CF that can be controlled. And by controlling the asthma, I started to improve.
And just so you know, asthma sometimes has NO visible symptonms.
The same type of swelling of tissue happens in the sinuses. They too swell, and trap mucus. You get sinusitis and worse - the mucus drips down into the lungs causes exacerbations.
What to do? Avoid allergens, irritants, and chemicals. My doctor advises her patients to use vinegar, baking soda and water -- to be put into a spray bottle. I also use a few commercial products "Planet" and "Seventh Generation" bought at Whole Foods. Ideally you should remove all carpets, use fragrant free products whether it is your shampoo, soaps, or cleaning products. Put a filter in your shower head, use a great vacuum that doesn't spew back dust and exhaust, and buy a superior air filter.
Encase your mattress and pillowcases in allergy protective cases. Avoid furniture that has particle board (formaldehyde). Furniture that is leather or tightly woven is preferred. Keep your windows closed and the air conditioning going. If your child has a new mattress or sits on new furniture that has fire retardant, that can be a real trigger. Get rid of houseplants. Keep animals out of the bedroom. Don't wear any frangrance.
Yes, moving to a hot, humid climate can totally contribute to a dramatic increase in symptoms. My doctor tells her patients who are suffering like your son to move. If you hadn't moved I would have told you to look around your house and see if anything at all has been introduced into your child's life that is new. I think you do know what the problem is. Parents really do often seem to know.
There is a lot more. But here is a start.