Flu activity is on the rise worldwide amid a surge of COVID-19 cases driven by the omicron variant. A news outlet in Israel reported on Jan. 2, 2022, that the country saw its first case of a patient who contracted COVID-19 and flu at the same time. Since then, reports have surfaced of people infected with both flu and coronavirus in the United States and other countries.
A viral TikTok video about the double infection of COVID-19 and influenza in Israel, which some people have dubbed “flurona,” has been shared hundreds of thousands of times and received more than one million likes.
Viewer Mary emailed the VERIFY team, asking if COVID-19 and the flu have merged into a new strain.
Have COVID-19 and the flu virus merged into a new strain?
- Centers for Disease Control and Prevention (CDC)
- World Health Organization (WHO)
- Study published in Frontiers of Medicine journal
- Dr. Payal Kohli, assistant clinical professor of medicine at University of Colorado’s Anschutz Medical Campus
No, COVID-19 and flu have not merged into a new strain or variant because that isn’t possible. A person can be infected with both viruses at the same time, which is called a co-infection.
WHAT WE FOUND
The Centers for Disease Control and Prevention (CDC) says on its website it is possible to have flu and another respiratory virus such as COVID-19 at the same time.
Some social media users have expressed concerns that the flu and COVID-19 viruses have combined into a new strain. However, this isn’t the case. The World Health Organization (WHO) said in an emailed statement that it recommends use of the term “co-infection” of flu and COVID-19, which means a person is infected with both viruses at the same time rather than a new strain.
Dr. Payal Kohli, assistant clinical professor of medicine at University of Colorado’s Anschutz Medical Campus, further clarified that COVID-19 belongs to the coronavirus family of viruses, which is a separate family of viruses than the flu.
“A co-infection with two viruses means that you simultaneously are infected with the coronavirus and the flu virus, which are both separate viruses. You just happen to get infected at the same time,” Kohli said. “On the other hand, having a new strain or a new virus that can cause both illnesses at the same time is an entirely different process. So that is actually having a genetic virus that is a flu virus and a coronavirus, which is impossible, occurring at and causing both infections to occur simultaneously.”
The WHO said in its statement people are “often infected with multiple pathogens that co-circulate in the community; and as more people are getting tested, multiple pathogens may be detected.”
“This does not, however, necessarily lead to the emergence of a new disease entity (‘flurona’, as reported) when influenza and SARS-CoV-2 co-infect the same individual,” the WHO wrote.
Contrary to some news reports, the case of flu and COVID-19 co-infection out of Israel is not the world’s first. Case reports and studies documenting influenza and COVID-19 co-infection were published as early as April 2020, according to the WHO.
The prevalence of COVID-19 and flu co-infection remains “relatively low” based on recent studies, the WHO said. A study published in the journal Frontiers of Medicine also concluded that a “low proportion” of COVID-19 patients had flu co-infection.
Kohli said people who are immunocompromised and those who have not received their COVID-19 and flu vaccines are among the groups who are at higher risk of having both infections at the same time.
COVID-19 and flu vaccines remain the best defenses against both viruses. According to the CDC, a person can get a COVID-19 vaccine and other vaccines, like the seasonal flu shot, during the same visit to the doctor or pharmacy. The public health agency also says on its website that people no longer need to wait 14 days between vaccinations as they previously recommended.