The holiday season often means traveling and spending time in close quarters with family and friends. However, this festive period also brings a surge in winter illnesses, including the flu, RSV, and norovirus, as indicated by federal statistics.

This year, an especially concerning strain known as the ‘super flu,’ specifically the H3N2 subclade K, is causing an unusual spike in flu cases much earlier than usual.

In early December, the U.S. recorded its first flu-related pediatric fatality for the 2025-26 season. Reports from both the CDC and Colorado health officials have confirmed this. Although it remains unclear if the child in Colorado is the same as the one in the CDC’s report, state authorities revealed that an elementary school-aged child passed away last week.

While Colorado reported the first fatality, other areas might not be far behind. The CDC’s latest data indicates that individuals residing in or visiting New York City face the highest flu risk this holiday season, as the city has reported ‘very high’ flu activity as of December 6.

With the subclade K strain proliferating nationwide, actual infection rates could be much higher. Meanwhile, respiratory syncytial virus (RSV), which poses significant risks to infants and the elderly, continues to climb alongside Covid cases.

And with subclade K strain climbing nationwide, actual figures could be significantly higher. Respiratory syncytial virus (RSV), which is particularly dangerous for young babies and the elderly, is also rising alongside Covid.

CDC epidemic trends data shows, too, that the surges are going to worsen in nearly 36 states in the coming weeks.

In many cases of these viruses, people will recover with little more than over-the-counter flu and cold medicine.

The latest CDC data shows states where COVID, the flu and RSV are on the rise this holiday season (stock image)

However, Dr Neal Shipley, medical director of Northwell Health-GoHealth Urgent Care, told Daily Mail it is important to recognize the symptoms that ring alarm bells so you know when to seek expert help.

‘If your symptoms worsen quickly, or you have trouble breathing, weakness, dehydration or symptoms that don’t improve after a few days, you should find your nearest urgent care,’ he said.

Now, based on laboratory tests and federal wastewater data, which tracks larger community spread, the Daily Mail can reveal where you have the highest risk of getting sick this winter.

The latest CDC data, which was updated on December 6, shows virtually no corner of the US is safe from infection with one of the viruses.

Flu

New York City is recording the highest levels of the flu, and those headed to the Big Apple might feel sick after their trip. 

The greater New York state, New Jersey, Colorado and Louisiana all recorded ‘high’ flu activity. 

Idaho, Texas, Georgia, South Carolina, Michigan and Massachusetts reported ‘moderate’ influenza A activity, while the rest of the country had ‘low’ or ‘minimal’ activity. 

Influenza A makes up three in four flu cases in the US. It is also on the rise, largely due to the increased prevalence of H3N2 subclade K. 

CDC data released on December 12 shows an eight percent increase in Americans testing positive for the flu virus compared to the week prior, and about 3 million have contracted it so far. There have been 1,200 recorded deaths from the flu this season. 

Typical flu symptoms usually come on abruptly and include fever, fatigue, chills, headache, cough, body aches, congestion, runny nose and coughing. Experts have noted that while H3N2 subclade K’s symptoms are not different from other flu variants, they may be more severe. 

Shipley told the Daily Mail that in children, the flu comes on suddenly and may also cause vomiting and diarrhea. He also said people over the age of 65 are at the highest risk of complications, including hospitalization and death.

Influenza A can best be prevented with the seasonal flu vaccine, which tends to be about 30 to 75 percent effective.

RSV

For RSV, wastewater data shows ‘very high’ activity levels in Wyoming and Louisiana, and ‘high’ levels in Kentucky. 

Alabama and Florida each had ‘moderate’ activity. California, Nevada, Texas, Arkansas, Tennessee, Georgia, Maryland and Connecticut all reported ‘low’ RSV activity, while the rest of the country had ‘very low’ levels.

There was no data available for Montana, North Dakota or Arizona. 

RSV is a particularly dangerous infection for young children because it can cause inflammation that may block their small airways, potentially leading to death.

About 58,000 to 80,000 children younger than five years old are hospitalized every year due to RSV, and 100 to 500 children die from the infection.

It spreads via respiratory droplets often from coughs and sneezes, and causes symptoms including a sore throat, runny or stuffy nose and exhaustion. In severe cases, patients can start wheezing.

The disease can also be fatal for older adults who are more prone to complications such as pneumonia. 

RSV can be prevented with a single-dose vaccine given to pregnant mothers, newborn babies and adults over age 65. Experts estimate the vaccine is 80 percent effective.

COVID-19

Connecticut, Nebraska and Vermont all reported ‘high’ levels of COVID-19, which are likely fueled by the rise of the XFG ‘stratus’ variant that patients claim feels like ‘razor blades’ in their throats.

Indiana was the only state to report ‘very high’ COVID activity levels in wastewater based on reporting from 27 sites.

Kansas, Minnesota, Oklahoma, Alabama, Tennessee, Kentucky, Ohio, Pennsylvania, New York, New Hampshire and Maine all had ‘moderate’ COVID activity. 

The remainder of the US reported ‘very low’ levels except for New Mexico, which had ‘low’ activity. 

There was no COVID wastewater data for Montana or North Dakota.  

CDC data suggests the dominant COVID variant right now is XFG. Patients report this variant has caused a painful sore throat that feels like it is being cut with a razor blade, which has been dubbed a symptom of this new mutant strain.

Other symptoms are similar to previous variants and include fever, chills, cough, shortness of breath, sore throat, congestion, runny nose, loss of taste or smell, fatigue, body aches, headache, nausea, vomiting and diarrhea.  

Like other winter illnesses, COVID tends to peak in late December and January. The CDC has not tracked COVID test positivity, deaths or hospitalizations since September 27.