The Immuno Act is legislation in the United States that provides liability protections for manufacturers of vaccines and other medical countermeasures during public health emergencies. Here are some key details about the Immuno Act:

• Full name: Public Readiness and Emergency Preparedness Act (PREP Act)
• Passed in 2005 to encourage rapid development of vaccines and treatments during public health crises.
• Provides immunity from liability claims to manufacturers and distributors of medical countermeasures like vaccines, except in cases of willful misconduct.
• Covers countermeasures administered and used according to public health authorities during declared emergencies.
• Established the Countermeasures Injury Compensation Program to provide benefits to those seriously injured by covered countermeasures.
• Invoked by the Secretary of Health and Human Services during public health emergencies to provide liability protections.
• Was invoked in 2020 to extend liability shield to COVID-19 vaccines and therapeutics authorized for emergency use.
• Proponents argue it is necessary to protect manufacturers from frivolous lawsuits during crises. Critics contend it removes accountability.

So in summary, the Immuno Act provides legal immunity for vaccine makers to encourage development of medical countermeasures vital during public health emergencies like the COVID-19 pandemic.