I wouldn't worry. As was noted in that topic, a weakened immune system comes first. Then aspergillosis.
Quoting from that topic: "Sources for aspergillus spores: everywhere. It is in the ground outside, therefore there are spores in your air. As with any fungus, it likes moisture. More moist environs especially with damp litter are great homes for fungus. A dirty cage which gets wet from a bird bath is a better home for aspergillus spores to make a home and release even more spores. If your backyard floods often or stays very moist (talking to you over-irrigators here) the fungal load in your yard will be higher and more spores will be in the air for your body to fight against.
Your best bet is prevention when it comes to aspergillosis. Make sure your parrot is healthy and getting enough vitamin A. Avoid creating areas where aspergillus thrives and can overwhelm the system.
Also, roasting has not been shown to reduce aspergillus spores as of yet."
The chances of your bird having a weakened immune system PLUS being exposed to enough spores just from peanuts to create a problem are slim. If you're worried, feed the peanuts in moderation. As Ellie said, nuts meant for human consumption are much less likely to have high amounts of aspergillus spores. They're checked like crazy. If you want to avoid aspergillus, your bird needs to live in a bubble (it's everywhere!).
I do believe the problem with aspergillosis in parrots stems from lack of nutrition, therefore a weak immune system. It's my personal opinion, but has a little bit of science to back it up (particularly when it comes to Vitamin A deficiency). Feed red/orange veggies and dark leafy greens- those are high in beta-Carotene which is the precursor to vitamin A. Vitamin A is a fat soluble vitamin- which means you can have too much when using artificial supplements. Nature's way of giving us vit A through veggies is by providing beta-Carotene which our body can use to form vitamin A as needed without the risk of overdose.
Just as with humans, much can be done for the body with the proper diet.
