- Health Insurers Had Their Best Quarter in Years, Despite the Flu Bloomberg News by Zachary Tracer — U.S. health insurers just posted their best financial results in years, shrugging off worries that the worst flu season in recent history would hurt profits. Aetna Inc., for instance, posted its widest profit margin since 2004. Centene Corp. had its most profitable quarter since 2008. And Cigna Corp., which reported on Thursday, had its biggest margin in about seven years. Analysts at Morgan Stanley, in a research note, said insurers are in the midst of a "hot streak." One big reason for the windfall is the tax cuts passed by Congress last year, which in some cases more than halved what the insurers owe the government. Aetna said its effective tax rate fell to 16.8 percent from 39.6 percent, for example. Many insurers also spent less on medical care than analysts had expected, even taking into account increased spending on flu treatments.