‘Flurona’ Cases Raise Concerns Of Severe Double-Infections

Topline

Israel reported a rare case of simultaneous infection with Covid-19 and flu Thursday, raising concerns that seasonal flu outbreaks could leave large swathes of the public vulnerable to severe Covid infections.

A throat swab sample is placed inside a container to be tested for coronavirus on August 24, 2020 in … [+] Bonn, Germany.

Andreas Rentz/Getty Images

Key Facts

The dual infection, apparently Israel’s first, was found in an unvaccinated pregnant woman who showed mild symptoms, Petah Tikva’s Beilinson Hospital told the Times of Israel.

Paradoxically, a season with little flu transmission can leave people more vulnerable the following year because they have not been exposed to the virus, which has now led to widespread outbreaks of both Covid and the flu in Israel, Ben-Gurion University School of Public Health Director Nadav Davidovitch told CNN Tuesday.

Masking and lockdowns intended to curb Covid helped push infections of flu and other respiratory diseases to record lows in the U.S. last winter, raising the possibility of greater vulnerability to flu outbreaks this year.

Overall vaccine coverage for the 2021-2022 flu season is similar to or lower than the previous season, with vaccination among children aged 6 months to 17 years down 5.9 percentage points in December 2021 compared to the previous December, the Centers for Disease Control and Prevention reported.

Nearly 30% of people 18 and over in the U.S. do not plan to receive a flu shot, according to CDC survey data collected in December 2021.

Additionally, current vaccination rates may paint an overly optimistic picture—a study led by University of Pennsylvania microbiologist Scott Hensley found that recent mutations in the most common flu strain may have rendered vaccines partially ineffective against it, CNN reported.

Key Background

Flu infections often surge in the winter due to favorable temperature and humidity conditions. Flu and Covid share symptoms including fever, headache, cough, muscle aches and fatigue. Though the “flurona” patient identified in Israel was discharged “in good general condition,” doctors warned that contracting both viruses at once could have severe health consequences, the New York Times reported. Though there have been few confirmed cases of double-infection with Covid and flu, as many as 70% of patients hospitalized with flu symptoms may test positive for more than one virus, according to a 2019 study published by the National Center for Biotechnology Information.

Big Number

199. That’s how many children died of flu in the U.S. during the 2019-2020 flu season, the CDC reported. Compare that to just one death during the 2020-2021 season, when flu vaccines were distributed in record numbers. Vaccine coverage during the 2020-2021 season was 52.1% among the general population and 58.6% among children.

Contra

Thanks in part to harsh travel restrictions, Australia’s May-August flu season dropped from 219,329 infections in 2019 to 771 cases in 2020, according to figures published by the Australian Broadcasting Corporation. However, contrary to predictions that an unusually mild flu season will be followed by an unusually harsh one, infection numbers fell again in May-August 2021 to 201 cases. Even more confounding is the fact that this drop in flu infection coincided with a drop in flu vaccination rates from 2020 to 2021, according to Australian Department of Health data. One explanation is that Australia’s travel restrictions “likely disrupted external and local seeding” of the virus, World Health Organization spokesperson Margaret Harris told the Washington Post.

Surprising Fact

Though some outlets referred to Israel’s recently identified “flurona” case as the world’s first such double-infection, the Atlantic reported the case of a New York man who tested positive for both viruses in February 2020.