Thank you for your question. I look forward to working with you to provide you the information you are seeking.
HIPAA applies to healthcare providers and insurers. There are exceptions in there when the provider is acting in the capacity of an employer and not provider, since employers need to disclose information as needed to conduct business and thus would not be a HIPAA issue. In your example, if an employee calls into a supervisor with an illness and nature of the illness as required by the employer, then the supervisor has the right to disclose that to those other employees/supervisors as necessary to conduct the business of the employer.
2) Yes, an employer is allowed to ask the employee their expected date of return. The employer can even ask for a medical note documenting the nature of the illness that caused an employee to miss work. This is permissible.
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