The United States started the new year awash in respiratory illness, with high levels of flu, Covid-19 and RSV across most of the country. The latest data from the US Centers for Disease Control and Prevention notes that some measures of flu activity dipped in early January, but the single week of decrease is not a trend – and experts warn that more increases are likely to come.
“It’s actually pretty common that we see a little bit of a dip around the holidays, but we typically see an increase after that – because people will delay seeking care, and lots of people get exposed to different things through holiday travel,” said Janet Hamilton, executive director of the Council of State and Territorial Epidemiologists. “I think we should definitely expect a lot more respiratory virus activity.”
Respiratory virus activity was high or very high in all but 15 states during the week ending January 6, according to the CDC.
In the latest update this week, and consistently through the season, the agency’s Center for Forecasting and Outbreak Analytics has suggested that this respiratory disease season will probably result in a similar number of hospitalizations as last season. And while current hospital capacity is considered stable overall, the CDC says that hospitals in some parts of the country have reported strains on their resources due, in part, to increases in respiratory illness.
“There’s still a substantial amount of respiratory virus season to go. These viruses, to one degree or another, will be with us through the end of this month and well into February,” said Dr. William Schaffner, an infectious disease expert at Vanderbilt University.
Last month, flu surpassed Covid-19 to become the leading respiratory virus driving emergency room visits. The CDC estimates that flu has caused at least 14 million illnesses, 150,000 hospitalizations and 9,400 deaths this season.
Covid-19 hospitalizations have also been on the rise for weeks, more than doubling since the beginning of November. There were nearly 36,000 new Covid-19 hospitalizations during the week ending January 6, CDC data shows.
Covid-19 infections are less likely to cause severe disease now than they were earlier in the pandemic, thanks to greater immune protection in the population from vaccination and prior infection. But wastewater surveillance suggests that viral activity is very high in the US, and experts caution that it’s not a time to get complacent.
“We might be tired of it being respiratory virus season in the winter, but it shouldn’t surprise us. Just because you’ve experienced flu or Covid or RSV and been fine before doesn’t mean that’s what’s going to happen the next time,” Hamilton said. “We’re dealing with things that we feel more familiar and comfortable with, but being ready for yourself and your family is the most important thing that you can do.”
There are still benefits to getting a flu shot this season if you haven’t already, the CDC says. It’s recommended as long as viruses are spreading, and there’s evidence that this year’s shot is particularly helpful.
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Early data from Canada found the flu vaccine to offer strong protection this season, supporting earlier evidence from South America. Overall, the vaccine has been more than 60% effective against the prominent influenza A strain circulating in the US, and it’s been even more effective at protecting children under 10. Last season, overall effectiveness was less than 50%.
Still, less than half of the US population has gotten the flu shot this season, according to the CDC. Only about 1 in 5 adults and fewer than 1 in 10 children have gotten the latest Covid-19 vaccine.
“If you haven’t been vaccinated, yes, it’s very late, but it’s not too late. Don’t linger – get the vaccines this afternoon,” Schaffner said.
“Get that mask out of your bureau drawer and put it on when you go to a basketball game or religious services, when you go to the supermarket and things such as that. Exert a bit of caution, because these are very contagious viruses.”