Fact Check: Is Hantavirus infection a side effect of Pfizer COVID-19 vaccine?
WASHINGTON, DC: Social media platforms were flooded with claims alleging Hantavirus infection is a side effect of Pfizer’s COVID-19 vaccine, triggering confusion and renewed debate around vaccine safety misinformation.
The claim gained traction after users circulated excerpts from Pfizer submissions to US regulators, suggesting that hantavirus pulmonary infection was listed among possible vaccine-related adverse events. The posts spread widely across Facebook and X, with some users misrepresenting regulatory safety documents as proof of causation.
Claim: Hantavirus infection is linked to Pfizer COVID-19 vaccine side effects
According to viral posts, hantavirus pulmonary infection is allegedly caused by the Pfizer-BioNTech COVID-19 vaccine. A Facebook post dated May 7 shared a screenshot of Pfizer documents submitted to the US Food and Drug Administration in 2021, pointing to a section titled “List of Adverse Events of Special Interest.”
The post claimed that hantavirus pulmonary infection appeared in the list of vaccine side effects. Similar claims on X went further, with some users falsely asserting that the vaccine contained hantavirus itself.
The posts referenced a Pfizer appendix that includes a broad list of medical events tracked during clinical trials.
Fact Check: No evidence supports claim of vaccine causing hantavirus infection
However, Pfizer has clarified that inclusion in the document does not establish any causal link between the vaccine and hantavirus infection. The appendix was part of routine safety monitoring during clinical trials conducted between December 2020 and February 2021 and included all reported medical events, regardless of whether they were related to the vaccine.
Health authorities note that systems such as the US Vaccine Adverse Event Reporting System collect voluntary reports to monitor safety signals and do not confirm causation.
According to the US National Institutes of Health and the World Health Organization, hantavirus infections are caused by exposure to infected rodents, not vaccines. Pfizer has also confirmed that its COVID-19 vaccine, now marketed as Comirnaty, does not contain hantavirus or any live virus components.
Trump comments on virus monitoring and transmissibility status
Separately, Donald Trump told reporters that officials are closely monitoring the virus situation and said it is “not easily transferable.”
“No, we seem to have things under very good control. They know that virus very well. It’s been around a long time,” he said.
He added that experts are studying the situation closely, noting that it differs from COVID-19 in terms of transmissibility.
