Flu activity is picking up across the country, indicating an earlier start to this year's flu season, particularly in the South and in the West, according to the Centers for Disease Control and Prevention.

The uptick doesn't necessarily mean it's going to be a bad season — flu is notoriously unpredictable — but some clues from earlier this year point to a potentially harsh season, NBC News reports. The flu season in Australia, which can be a sign of what's to come in the Northern Hemisphere, arrived early and with a vengeance.

Friday, the CDC reported widespread flu in five states: Alabama, California, Louisiana, Nevada and South Carolina. This time last year, no states showed widespread activity.

In addition, high levels of flu were reported in seven states — Alabama, Arkansas, Georgia, Mississippi, Nevada, South Carolina and Texas — plus Puerto Rico. Last year, only one state reported high levels of flu at this time.

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