By Tim Loh

It’s been dubbed flurona: when a person is infected with the influenza virus and the Covid-19 coronavirus, either simultaneously or back-to-back. Cases are being reported around the globe, and experts say they are likely to grow as the more contagious omicron variant becomes more prevalent. The phenomenon, however, isn’t exactly new. Reports of such “co-infections” go back to early 2020.

1. Why is this getting attention now?

At a time when the world is bracing for every new twist in the pandemic, it’s understandable that the prospect of getting Covid and the flu at the same time is causing some people anxiety. And it’s no surprise that examples of this are emerging, given omicron’s remarkable spread and the fact that, with societies a lot more open than a year ago, the flu is staging a comeback after practically disappearing amid last year’s lockdowns and heightened focus on hygiene.

2. Should I be worried?

Not overly. If you do get Covid, you’re certainly better off if you don’t also get the flu, since a simultaneous infection would further tax your immune system, said David Edwards, an aerosol scientist and bioengineering professor at Harvard University. But the odds of that happening aren’t great. The likelihood of catching either virus on any given day is already very low for most people. “The probability of both of those things happening at the same time is sort of like the probability of getting robbed by two people on the same day,” Edwards said. “It happens, but it’s not like people should think, ‘Oh, there’s gonna be this flurona that’s going to overtake omicron.’ That’s not going to happen.”

3. What’s the effect of getting two infections at once?

In a meta-analysis of various studies last May, researchers from the University of Wisconsin found that 19% of people who tested positive for Covid simultaneously tested positive for another pathogen (a so-called “co-infection”) -- be it viral, bacterial or fungal. They found that 24% of patients diagnosed with Covid afterward tested positive for a different pathogen (a so-called “superinfection”). For both categories, the situation was associated with “poor outcomes, including increased mortality,” the authors found. The research underscores the need to test for ailments beyond just Covid so that people can be properly treated, the authors said.

4. Is the flu back in full force?

In many countries, last year’s flu season was the least harmful in more than a decade. In the U.S., for example, hospitalizations from the flu were the lowest on record since data started being collected in 2005, according to the Centers for Disease Control and Prevention. So far this winter, respiratory illnesses with flu-like symptoms are tracking at levels much more comparable to pre-pandemic years, the CDC said. That’s probably a function of there being less social distancing and attention to hygiene, but also because people’s immune systems are less equipped to fight off influenza after being less exposed to it last year, Edwards said.

5. Where is flurona being reported?

Israel confirmed one of the highest-profile cases in late December when a pregnant woman -- who hadn’t received Covid vaccines -- tested positive for both Covid and flu at a hospital, according to reports. She reportedly experienced mild symptoms and has been released. Omicron has caused a surge in new coronavirus cases in Israel, which is also seeing a rise in influenza this winter after being largely spared the pathogen a year ago. Cases of the double infections have also been reported in Spain -- and, as early as February 2020, in the U.S. Three states in Brazil have reported instances.