Here comes the 2018-19 US flu season

Fig. 1. CDC influenza-like illness activity, Dec. 22.

Officially, according to a CDC statement on Dec. 21, “It’s too soon to make any assessment about this season’s severity.” The public health agency’s plot (Fig. 1) of “influenza-like activity,” which is a based on outpatient visits to a national network of healthcare providers, shows that activity was ramping up rapidly toward the end of 2018; how far up the plotline goes will determine the severity overall. (Of course, only when it reaches epidemic proportions will consumers scramble to get their vaccinations, which then take days to take effect).

Retail drugstore giant Walgreens provides its own Flu Index, based on store activity for flu shots and remedies. Its data (Fig. 2) show that flu-related consumer purchasing is elevated in Nebraska, Texas, Alabama and Georgia. CDC provides similar national maps, but based on other criteria (Fig. 3). Both sources note that data are preliminary and subject to week-by-week change.

Fig. 2 Walgreens' Flu Index, Dec. 22.

In a manner of speaking, the pharma industry is banking on a severe flu season: the volume of dosages distributed is at a historic high of 166.6 million. In recent years, the supply has varied from 114 million (2009-10) to 155.3 million (2017-18). Making these dosages available represents some heavy lifting by wholesalers and distributors beginning around September, which follows a production season that begins in spring and continues for most of the rest of the year.

Fig. 3. CDC's map of flu activity, Dec. 22.