As congressional Republicans’ efforts to repeal and replace the Affordable Care Act remain in limbo, the Trump administration and some states are taking steps to help insurers cover the cost of their sickest patients, a move that industry analysts say is critical to keeping premiums affordable for plans sold on the law’s online marketplaces in 2018.

This fix is a well-known insurance industry practice called reinsurance. Claims above a certain amount would be paid by the government, reducing insurers’ financial exposure and allowing them to set lower premiums.

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