Both me and my wife were diagnosed with hyperthyroid conditions within a years time, I had a radiation treatment, which worked for me, but the same treatment did not work for my wife. Why?
So my question would be here is --- how stressed out are both you and your wife - Has there been any trama in your relationship or outside that could bring on a huge amount of stress in your lives. Was there an accident?
It not a disease that is "catchable" but if you both live exhausting mental or physical lifestyles - you both can have too stressful lives and develop some conditions.
It is an "individual disease" which means each body reacts differently to treatment and recovery.
You don't catch thyroid conditions but you probably have similar life conditions. My dr. said each decade older we get our chances of having thyroid problems increases. Within a year of my being diagnosed with thyroid cancer my husband had to go on synthroid. I joked that he didn't want me getting all the thyroid attention. It is the only medication either of us take.