OK, I misunderstood "antiviral" to mean vaccination, not post-exposure medication. That certainly makes a difference. However, I cannot see how the type of infection (swine flu, seasonal flu, etc.) affects the medication-payment decision.
A potential misunderstanding -- the payer (the worker-comp insurance carrier versus the employer versus the employee). For the carrier to pay, the employee must submit a valid claim of injury and show work-relatedness. For the employer to pay, a employee-supporting internal policy or management decision is required. If neither of those pay, then the employee must pay (invoking personal medical insurance if available).
The employee may have difficulty proving that a pandemic infection is work-related if the employee might have been exposed while in the community, or if PPE use was inconsistent. For example, see http://www.heart-intl.net/HEART/OccI...ndex%20m-z.htm
(Disclaimer: I am not an attorney, don't play one on TV, and do not hold out myself as an expert in this area!)
I don't understand your other question about local health policy overriding OSHA. Do you have examples?
We healthcare people are certainly on for a long, hard ride -- years ago it was polio and measles, then later HIV and SARS, and now swine flu. Every one of those, and whatever is to come next, has been scary and confusion-filled at first. I think we continue to learn and improve how we handle mass illness.