It is safe and effective to get a flu shot at the same time as a Covid-19 vaccine, according to a new U.K. study, lending support to U.S. health officials as they roll out coronavirus boosters while urging people to protect themselves from the dangers of flu.
The trial, which monitored the side-effects and immune responses of 679 people across the U.K. after vaccination with both shots, raised “no safety concerns” about administering shots for flu and Covid-19 together, the researchers said.
Reported side effects—including fatigue, injection site pain and headache—were mostly “mild or moderate” and in line with what is expected from either vaccine individually, the preprint study found, which has not yet been peer-reviewed or published in a scientific journal.
Blood tests on the volunteers, who had already received one dose of AstraZeneca or Pfizer’s Covid-19 vaccine and were tested receiving their second Covid-19 dose alongside a placebo or one of three different flu vaccines, indicated no negative effect on immunity for either vaccine.
Given the novelty of the technology used to build the Pfizer and AstraZeneca shots, the researchers warned the study’s findings may not apply to other Covid-19 vaccines in the same class (like the Moderna vaccine).
Combining Covid-19 vaccines with flu shots should help “reduce the burden on healthcare services,” the researchers said, as well as allow vaccines to reach those who need them most more efficiently.
What To Watch For
The full results of the study are due to be published in the Lancet medical journal.
Throughout the first year of the pandemic, experts warned of an impending “twindemic,” a devastating mixture of Covid-19 and influenza, or flu. This did not happen. The public health measures put in place to control Covid-19 helped to practically wipe out the flu in the U.S., as well as a number of other common respiratory illnesses. Now that restrictions have eased, however, experts are divided as to what happens when, not if, it returns. It could be less dangerous having not had much chance to evolve or it could meet a more vulnerable population that haven’t been exposed to the virus. Experts are advising everyone to get vaccinated against both diseases and warn outbreaks of flu could stretch already overwhelmed hospital systems.
650,000. That’s about how many people worldwide are killed by the flu every year, according to the World Health Organization. It causes around 5 million cases of severe illness.
The Safety and Immunogenicity of Concomitant Administration of COVID-19 Vaccines (ChAdOx1 or BNT162b2) with Seasonal Influenza Vaccines in Adults: A Phase IV, Multicentre Randomised Controlled Trial with Blinding (ComFluCOV) (Lancet Preprint)
Pfizer Tests First mRNA Flu Shot In Patients As Firm Builds On Covid Vaccine Success (Forbes)
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