The spread of the flu is also driving more patients to see their doctors. The Centers for Disease Control and Prevention said flu activity was at moderate to high levels in two-thirds of the nation at year's end, when flu-related hospitalization increased. That has analysts wondering whether fourth-quarter results for health insurers will be hurt by flu-related medical costs.
"While flu costs are seasonal and not indicative of underlying cost trends, they can have marginal impact on health plan medical costs and hospital volumes and can be challenging to disentangle from underlying trend estimates," wrote Brian Wright, health-care analyst at Sterne Agee.
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Wright estimated Medicaid players Centene and Wellcare Health Plans have the biggest exposure to states that reported the highest levels of severe flu activity at year-end, followed by Molina Healthcare.
For hospitals severe flu seasons result in higher volumes. Those with the greatest exposure to the hardest-hit flu regions include HCA Holdings, Community Health and Tenet Health Care, according to Wright.