Earlier quoted context omitted.
> My wife is, after 3 weeks, still really ill. Probably because she's working full time In my opinion it’s high time to call in sick. She is neither helping herself nor her coworkers by going to work.
If that's an option. I lot of people cannot call in sick. Being sick means being unpaid, and many people cannot afford to go unpaid.
In Germany being sick means full payment by the employer for 6 weeks, after that you'll receive around 90% of your last net income by your healh insurance company for 72 weeks, after that slightly lower unemployment payments for another 12 month. So around 2.5 years of being sick are required until you're actually unpaid.