Is It Safe to Get Your COVID and Flu Shots Together?

Many patients hesitate to receive their COVID-19 and influenza vaccines on the same day because of safety concerns. However, a landmark study has provided robust evidence supporting same-day vaccine safety for coadministered immunizations. Consequently, healthcare providers can confidently recommend coadministration to streamline clinical visits.

Evaluating Same-Day Vaccine Safety Across Formulations

The study evaluated more than 2.5 million participants within the U.S. Department of Veterans Affairs database. Specifically, researchers compared patients receiving both COVID-19 and flu shots with those receiving the flu shot alone. Furthermore, they tracked these individuals across three distinct vaccine eras involving bivalent, XBB-adapted, and KP-adapted formulations.

Importantly, the investigators measured 90-day risks for 46 prespecified adverse events. They grouped these events into three composite severity tiers to simplify analysis. Ultimately, the results showed no significant difference in risk between the two groups for any of the composite tiers.

Key Clinical Findings and Minor Risks

The research team found that serious or clinically significant events did not increase with coadministration. For instance, severe conditions like myocarditis remained extremely rare in both groups. In addition, the confidence bounds for all major safety tiers included the value of 1.0, signifying no added risk.

Meanwhile, the analysis revealed nominal statistical significance for only two less severe events. Specifically, patients receiving both vaccines had a slightly higher rate of syncope. Conversely, the coadministered group showed a slightly lower risk of tinnitus. Nevertheless, neither of these findings remained statistically significant after the team applied multiple-comparison corrections. Therefore, clinicians can assure patients that combining these updated formulations is highly secure.

Frequently Asked Questions

Q1: Does getting the COVID-19 and flu vaccines on the same day increase the risk of serious side effects?

No, the latest clinical data show that coadministration does not increase the risk of serious or clinically significant adverse events. Indeed, the safety profile is equivalent to receiving the influenza vaccine alone.

Q2: Were there any minor side effects associated with same-day vaccination?

The study observed nominal increases in syncope and minor decreases in tinnitus. However, these small differences were not statistically significant after adjusting for multiple comparisons, meaning they likely occurred by chance.

Q3: How does this study apply to newer, updated vaccine formulations?

Importantly, this target trial emulation specifically analyzed newer bivalent, XBB-adapted, and KP-adapted formulations. Thus, the reassuring safety findings are highly relevant to the latest immunizations used today.

References

1. Xie Y et al. Adverse Events After Same-Day COVID-19 and Influenza Vaccination Versus Influenza Vaccination Alone : A Target Trial Emulation. Ann Intern Med. 2026 Jun 30. doi: 10.7326/ANNALS-26-00217. PMID: 42372279.
2. Neale T. May as Well Get COVID and Flu Shots on the Same Day, Study Says. MedPage Today. 2026 Jun 29.