Alaska's state epidemiologist says it is facing “one of the sharpest surges” in Covid-19 in the US, adding that it’s not clear when the situation might stabilise.

“A lot of it’s going to depend on vaccination coverage rates” and measures such as masking, distancing and avoiding crowds, Dr Joe McLaughlin told reporters.

Health officials said hospitals are stressed, with staffing and capacity issues. The state health department reported about 20 per cent of patients hospitalised in Alaska have Covid-19.

McLaughlin said Covid-19 cases “really started to go up in early July, and we’re still on the upward trajectory”. He said Alaska has one of the highest case rates in the nation right now.

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