The infectious disease forecast for Thanksgiving is looking dicey

As Americans prepare for the Thanksgiving holiday this week, respiratory viruses are ramping up, creating hazardously infectious conditions for mass travel and multi-generational family gatherings.

Flu is on the rise in most of the country, with six Southern states and the District of Columbia already seeing high levels of influenza-like illnesses (ILI) activity. Louisiana has reached "very high" ILI activity, the Centers for Disease Control and Prevention reported in the latest flu surveillance update. The percentage of flu tests coming back positive is also increasing nationwide, with only one region, the Mid-Atlantic region, showing a stable week-over-week positivity rate. But the CDC noted that its rate overall is trending upward.

This year's flu season is again starting early; the current flu activity levels are about four to six weeks ahead of when we usually see them. And with activity already at highs in many states, there's a good chance that we'll once again see extremely high levels in some places—moving from red to the dreaded deep purple on CDC's scale, which we saw last year.