Aetna Inc. will start selling individual insurance plans through Costco, a wholesale club operator, in nine states. The Costco Personal Health Insurance program will include five health plans online, providing major medical benefits, dental and lower copays on prescriptions filled at Costco pharmacies. The plans will sell in Arizona, Connecticut, Georgia, Illinois, Michigan, Nevada, Pennsylvania, Texas and Virginia. Insurers like Aetna that have focused mostly on the larger employer-sponsored coverage market want to grow their individual business so they can remain competitive if more insurance is purchased that was in the future said Morningstar analyst Matt Coffina. Aetna is the third-largest private health insurer. Costco Wholesale Corp. operates 434 club stores in the U.S. and Puerto Rico.