Hantavirus pulmonary infection is a disease caused by some hantaviruses, not the Pfizer-BioNTech COVID-19 vaccine, contrary to widely shared online posts that misrepresented a document listing potential medical events after inoculation.
“List of Pfizer Covid jab side effects includes Hantavirus pulmonary infection!” said a widely shared May 7 post, opens new tab on Facebook, which shared a screenshot of submissions Pfizer filed to the U.S. Food and Drug Administration in 2021 to get a biological license for its vaccine.
The narrative was also shared on X, opens new tab, with one post suggesting the COVID vaccine contained a hantavirus.
The reference to hantavirus pulmonary infection in the Pfizer document, opens new tab is on the fourth page, opens new tab of the nine-page appendix, titled “List of Adverse Events of Special Interest”.
However, this is not confirmation that the vaccine causes hantavirus pulmonary infection, a spokesperson for Pfizer said in an email. A disclaimer, opens new tab on page 6 of the document makes a similar point.
The document lists any medical event experienced by a person during the study period between December 2020, when the Pfizer-BioNTech COVID-19 vaccine was first authorised, opens new tab for emergency use, up to February 28, 2021, regardless of whether it was related to the vaccine, the spokesperson added. It was compiled using voluntary reports through various national reporting systems, such as the Vaccine Adverse Event Reporting System (VAERS) in the United States.
The appendix, which lists hantavirus pulmonary infection, includes any potential medical events that Pfizer would consider of special interest if they occurred during the study period.
Britain granted full marketing authorisation, opens new tab to the Pfizer vaccine in late 2022 after reviewing its safety, efficacy, and other information, including a list of adverse events identified as having a causal link with the shot.
These adverse events are published, opens new tab in Pfizer’s product leaflet, opens new tab. Hantavirus is not mentioned, opens new tab.
HANTAVIRUS AS A VACCINE INGREDIENT
Some hantaviruses cause hantavirus pulmonary infection or syndrome, according to the U.S. National Institutes of Health, opens new tab and the World Health Organization, opens new tab.
There are no hantaviruses in the ingredient list of the Pfizer COVID vaccine, now called Comirnaty.
According to Pfizer’s website, opens new tab, the Comirnaty shot does not contain live viruses.
As of May 7, an outbreak of hantavirus on a Dutch-flagged cruise ship has killed three people.
South Africa’s health ministry said on May 6 that the Andes strain of hantavirus was identified in two victims who had been evacuated from the ship to the country.
The World Health Organization said in an online factsheet, opens new tab that the Andes strain is the only hantavirus that has seen human-to-human transmission. Transmission remains uncommon and when it does happen is associated with “close and prolonged contact”, the WHO added.
The U.S. Food and Drug Administration did not respond to a request for comment. An FDA spokesperson said in a previous Reuters fact-check that reports to VAERS post-vaccination “do not necessarily mean that a vaccine caused a health problem”. Anyone can submit a report, regardless of plausibility, added the spokesperson.
VERDICT
Misleading. Hantavirus pulmonary infection appeared in a list of possible medical events that would be considered of special interest if they occured during the study period, regardless of whether the medical event was caused by the vaccine. Pfizer’s regulatory document lists events that were later found to have a causal effect, and this list does not include a hantavirus pulmonary infection.
(This article was refiled on May 11, 2026, to correct the reference in paragraph six to the Pfizer document and to clarify in paragraph seven that the document's appendix lists potential medical events that would be considered of special interest if they occurred during the study period.)
