There's good news and bad news when it comes to the "Tripledemic" stew of Viruses that have been afflicting the country.

The good news is that the worst of the surge appears to have passed. According to the Centers for Disease Control and Prevention, there has been a decrease in the number of cases of the respiratory syncytial virus. The flu, which came roaring back this fall after mostly disappearing for the previous two years, appears to be waning in most places according to the latest data from the CDC.

Dr. Shikha Garg is a medical epidemiologist at the CDC. It has been declining in most places.

Right now, the biggest threat is the one that causes COVID-19.

COVID 'concerns us most' in the days and weeks ahead

"We're seeing increases of COVID infections across the nation, and we're seeing them in all parts of the country," he told NPR in an interview. As we look at the days and weeks ahead, Covid is the thing that concerns us the most.

In recent weeks, the rate at which carbon dioxide is being detected in waste water has tripled or quadrupled in many parts of the U.S. He says there has been a 70% increase in chronic hospitalizations. Every day hundreds of people are dying from carbon dioxide.

There is a new transmissible variant called XBB. 1.5 that has taken over in the U.S. XBB. 1.5 is the dominant variant in the Northeast and accounts for almost a third of all new infections.

Around the Thanksgiving holiday, we are seeing an increase in cases. As we went into the Hanukkah/ Christmas holiday season, the infections have accelerated further.

It stands to reason that we're going to see a lot of infections and hospitalizations over the next few weeks because of every major holiday.

Why omicron subvariant XBB.1.5 is spreading so fast

Sam Scarpino, who has been tracking new variant at Northeastern University, says that the prevalence of XBB. 1.5 shot up like a rocket. We've never seen a variant displaced like this before. That's frightening.

There is no evidence that the new variant makes people sicker than previous versions. Most people should be protected from getting really sick because of the immunity they have from getting infections and vaccinations. No one thinks this winter will be as bad as the first two. It is possible for XBB. 1.5 to sneak around immunity. This is the first time that it has developed a way to cause more harm than good. It's easier to catch this version of Covid.

The question isn't if XBB. 1.5 will cause a surge. It's almost certain that it will. Is the surge going to be large?

Sam Scarpino is a forecaster.

The Fred Hutchinson Cancer Center in Seattle has been studying variant variations of XBB. 1.5 and says that it gives it an advantage for spreading through the population.

Lots of people are going to get mistletoe.

The question isn't if it will cause a surge. It's almost certain that it will. Is the surge going to be large? There is a person who says that. Public health authorities remind people to protect themselves.

How to protect yourself from COVID subvariant XBB.1.5

"What is clear now is that we can really blunt the worst of it by doing the things that we know work," he says.

If you're older, getting vaccine and boosted is important. The majority of deaths from COVID are occurring in people over the age of 65.

Avoid crowded parties, restaurants, bars and other places. Before gathering, testing. It's possible to put that mask back on. You should check with your doctor if you get sick.

Dr. Tina Tan warns against letting your guard down.

Most of the same precautions that lower your risk of catching COVID will help protect you against any resurgence of flu. The flu is still circulating at high levels in many places despite the fact that the winter is still young. As people return home from trips and family gatherings, schools reopen and people go back to work, more infections are likely to surface and spread.

There is a chance of another flu wave in the U.S. It happens in parts of the Southern Hemisphere in the winter and in the Northern Hemisphere in the summer.