UnitedHealthcare has filed rates to continue selling individual market coverage in Nevada and New York next year, meaning the nation's largest health insurer might maintain a small presence on new government-run exchanges in 2018.

New York regulators announced this week that UnitedHealthcare and 15 other health insurers have filed paperwork to return to the individual market, which in many states is suffering from a lack of competition as insurance companies announce exits for next year.

On Friday, the Chicago-based company that operates Blue Cross and Blue Shield plans in five states said it's started the process of returning to the individual exchanges in Illinois, Montana, New Mexico, Oklahoma and Texas.

None of the announcements is a guarantee that insurers will compete next year, but "it's a sign that there's still interest in participating in the market," said Cynthia Cox, a researcher with the California-based Kaiser Family Foundation.

The moves are confined to the individual market, where self-employed people and those who don't get coverage through work or the government buy health insurance. The individual market has undergone sweeping change with the federal Affordable Care Act (ACA), which prevents insurers from denying coverage to pre-existing conditions.

Health insurers have found it difficult to make money since ACA rules took effect in 2014, and several carriers have either hiked rates or dropped out of the market as a result. The health law provides subsidies to people who buy individual coverage through government-run "exchanges," but the ACA didn't create an alternate means for providing subsidized coverage if private insurers don't compete.

In recent weeks, several health insurers have announced plans to drop exchange markets during 2018 amid financial losses and uncertainty about future implementation of the health law. Connecticut-based Aetna, which is one of the nation's largest health insurers, announced in May that it would not compete next year on health insurance exchanges in any state.

Currently, UnitedHealthcare sells individual coverage through exchanges in just three states — New York, Nevada and Virginia — down from more than 30 in 2016. In New York, filing documents show the insurer is seeking an average rate increase of 38 percent for 2018 that would impact about 6,000 people with individual coverage.

"We have filed rates for 2018 exchange plans that will enable us to offer valuable benefits at sustainable premium rates," said Maria Gordon Shydlo, a UnitedHealthcare spokeswoman, in a statement. "Our decision is not final until we receive approval regarding rates and plan designs."

New York's governor announced that insurers that withdraw from the state's exchange could be banned from serving as managed care organizations within certain state public insurance programs including Medicaid. The company is not commenting on the governor's announcement, Gordon Shydlo said, but UnitedHealthcare does have a contract for Medicaid business in New York.

UnitedHealthcare has filed rates to continue selling exchange coverage next year in Nevada, Gordon Shydlo said, but isn't returning to Virginia.

Chicago-based Health Care Service Corp., which operates the Blue Cross insurers in Illinois, Texas and three other states, said Friday the health plan is submitting products and rates for individual coverage in 2018, but hasn't made final decisions.

Earlier this week, the Star Tribune reported that Minnesota's four primary health insurers in the individual market all have started the process of submitting rates for 2018, although details aren't yet available. It's too soon to say whether the health plans actually will compete next year, since carriers here still have time to withdraw.

Because of recently announced exits by health insurers, there are 45 counties across Missouri, Ohio and Washington state where individuals won't have a way to buy exchange coverage in 2018 unless other carriers enter the markets, Cox said.

The counties tend to be rural, she said, adding that they all provided majority support for President Donald Trump in the 2016 election. Trump is pushing to repeal and replace the ACA. As Congress works on the plan, the president hasn't committed to providing certain consumer subsidies that health insurers say are key to the sustainability of the exchange markets.

Twitter: @chrissnowbeck