The number of people killed by devastating California wildfires has risen to 79, with more than 1000 still missing.

The death toll is the worst the state has experienced, and insured losses are also expected to set records.

The Camp Fire, northeast of San Francisco, is still only 60% contained. It has wiped out the town of Paradise in Butte County, killing 76 people and destroying more than 12,000 buildings.

To the south, the Woolsey Fire, which is 40% contained, has killed at least three people and damaged exclusive beachfront areas including Malibu, while the Hill Fire ripped through Ventura County, north of Los Angeles.

A briefing from AM Best says all-year fire seasons are “the new normal” for California, forcing insurers to reassess and reprice their exposures.

“Urbanisation and growing population density in heavily wooded areas, as well as hotter, drier conditions resulting from rising temperatures and declining precipitation, are contributing to wildfires becoming an increasingly frequent peril for insurers and citizens of California,” the ratings agency’s briefing says.

“As this year has progressed, so have the wildfires that continue to engulf numerous areas of the state.”

AM Best says loss figures are not yet available, but this year will set new records.

Losses from the Carr Fire earlier this year are expected to hit $US2 billion ($2.78 billion), and Moody’s estimates losses of up to $US6 billion ($8.31 billion) from the present fires.

AM Best says the potential for historic losses “was already likely before the Woolsey Fire ripped through the wealthier area of Malibu, which has a median home value of about $US2.9 million ($4.02 million)”.

The number of hectares burned this year is already nearly double last year’s total – which was itself a bad year. Last year’s losses hit $US16 billion ($22.16 billion).

Bushfire and Natural Hazards Co-operative Research Centre CEO Richard Thornton told insuranceNEWS.com.au that while what happens in California is not a precursor to what will happen in Australia, there are lessons to learn.

“We need to change where people live and how they live,” he says.

The centre’s bushfire outlook, released earlier this year, shows many areas face above-normal risk this year, particularly along the drought-affected east coast.

“It will be a challenging season,” Dr Thornton says. “The demographic issues are just as bad here as they are in the US, and in many ways we have dodged a bullet in the past.

“Even Black Saturday in 2009 could have been so much worse. We have certainly not seen the worst possible outcome yet.”