The U.S.’s Winter Virus Season Stays Unpredicable: Update for January 30, 2026

COVID, influenza A, and RSV are generally falling in the U.S., but levels range from very high to very low in different states, and some regions are seeing rising risks in the past week. Meanwhile, measles cases are accelerating, and the U.S. may soon lose its status as having eliminated the disease.

This week’s update:

COVID, Flu, and RSV Activity Varies Widely; Measles Growing

Although the wastewater data from the past week is preliminary, the latest trends are unusual, with COVID rising in three of four U.S. regions. COVID still managed a decline nationally, due to a significant fall in the Northeast, but it is odd for COVID to rise in most of the U.S. this late in January.

Meanwhile, influenza A rose in half of the four regions. And RSV fell in two regions, was steady in a third, and rose in the fourth region. The time-varying reproductive number (Rt) estimated by the CDC indicates all three viruses are growing. The Rt of COVID is estimated at 1.10, influenza A is 1.10, and RSV is 1.20.

The wastewater data is varied by virus and region:

• Nationally: COVID is moderate; influenza A and RSV viral activity is low; and all three declined in wastewater in aggregate across the U.S. in the past week.
• Midwest: COVID is very high and increased in the past week. Meanwhile, influenza A and RSV are low and declining.
• Northeast: COVID and influenza A viral activity is moderate and on a rapid decline. RSV is also moderate, but the trend is uncertain at present.
• South: COVID and influenza A activity is low but rose in the past week. RSV activity is moderate and declining.
• West: COVID is low and rose this past week. (Since October, the West has experienced a long period of low or very low COVID viral activity.) Influenza A activity is moderate and rising, and RSV is low and rising.

At present, COVID is high or very high in 15 states and moderate in another dozen. With COVID, flu, and RSV risks at varying levels and with a curious diversity of falling and rising trends, it remains a good time to take some care. This winter’s virus season seems like it will be extended and variable into February.

Current Wastewater Viral Activity Levels for COVID, per the NWSS

Adding to the U.S.'s viral woes is an aggressively increasing level of measles infections. The US has already had as many measles cases in January as we experienced in all of 2023 and 2024 combined. The insanity of the current administration’s anti-vax policies and rhetoric is beginning to cause a needless increase in suffering and risks.

If you are 37 to 69 years old, you may need a measles vaccine. If you were born before 1957, it is assumed you are immune because the infection was so prevalent before the vaccine became available. People born after 1989 probably were vaccinated on the current schedule of two doses, which was recommended starting in 1989. So, it’s folks born between 1957 and 1989 who may only have a single dose and may wish to consider getting vaccinated.

COVID and flu and RSV and measles, oh my! Stay safe, friends.