In most (western, don't know otherwise) countries, you stay home when you're sick, and get paid because it's outside of your control. No matter if that is day 1 this year or day 20.
It's illegal to discriminate against someone because of their medical background or disability unless it's critical for the job. For medical background they wouldn't be able to get the information anyway.
Sickness is just part of the cost of doing business with people, not robots.