WHAT WAS CLAIMED
Pfizer listed hantavirus as a side effect of the COVID-19 vaccine.
OUR VERDICT
False. The list of adverse events of special interest is not a compilation of vaccine side effects.
AAP FACTCHECK - Hantavirus is not listed as a side effect of the COVID-19 vaccine, despite social media claims.
While hantavirus pulmonary infection is among several hundred adverse events of special interest (AESIs) listed in an internal Pfizer report, it is not listed as a vaccine side effect.
Experts say an AESI is a pre-determined medical condition or procedure that drug makers want to monitor in patients after vaccination.
Global public health agencies are trying to contain a deadly hantavirus outbreak that emerged aboard a cruise ship in the South Atlantic in April 2026.
The claim is made in an Australian Instagram user's video with overlay text that reads: "When you realise the Hantavirus is listed a side effect of the Covid shot..[sic]."
An image appears on screen showing a list of several medical conditions with the words "hantavirus pulmonary infection" circled in red.
"They make the problem. They profit from the problem. They 'fix' the problem. All while working to destroy us in the process," the caption reads.
A New Zealand Facebook user posted the same claim, warning followers not to fall for the "pandemic scam" again.
However, hantavirus is not listed as a side effect of the Pfizer COVID-19 vaccine.
The image in the posts matches a list of medical conditions and procedures in an internal Pfizer document released in 2021 under US freedom of information laws.
The document details safety data and "adverse events" for Pfizer's COVID vaccine.
The condition "hantavirus pulmonary infection" is listed among hundreds of conditions and procedures in an appendix titled "adverse events of special interest" that starts on page 30.
Social media users claim that this list details the Pfizer vaccine's side effects.
But experts told AAP FactCheck that the list is actually pre-determined and includes medical conditions and procedures that clinicians want to monitor in patients, not necessarily those caused by the vaccine.
Jake Scott, an infectious disease expert at Stanford University, said the appendix is a "watch list" for things clinicians would want to review if they were reported.
"The point of building the list ahead of time is to cast a wide net so nothing slips past unnoticed," Dr Scott told AAP FactCheck.
"A condition being on the list tells you only that the safety team wanted to be alerted if it came up. It carries no information about causation."
Terry Nolan, a clinical epidemiologist at the Doherty Institute, also said that AESIs are a "watch list" in clinical trials and don't mean a condition is caused by a vaccine.
He said the pre-specified conditions in the list may be included because they occur with the disease the vaccine is intended to prevent, are "theoretically plausible" conditions that could arise among participants, or have been seen in animal studies.
"The condition may also have been identified in previous human clinical studies of similar or other vaccines, but its association occurred by chance," Professor Nolan told AAP FactCheck.
The Pfizer document explains (p16) that the AESI list was compiled from a series of third-party sources, including the US Centers for Disease Control and Prevention.
It includes "events of interest due to their association with severe COVID-19 and events of interest for vaccines in general," the document states.
Dr Scott explained that many conditions and procedures on the list could not feasibly arise as vaccine side effects, such as caesarean section and routine blood tests.
"These items are on the list because safety surveillance is supposed to be broad," he said.
"Hantavirus pulmonary infection sits in that same nine-page alphabetical catalog for the same reason.
"It's a severe viral lung illness that overlaps clinically with COVID-19, so it was worth flagging in case a report ever came in."
A table in the document (p16) lists which of the AESI had actually been observed among vaccinated patients as at February 28, 2021. Hantavirus pulmonary infection is not listed.
Pfizer also confirmed that hantavirus is not a listed side effect of its vaccine.
"Hantavirus infection is not listed as a side effect on the Pfizer‑BioNTech COVID‑19 vaccine summary of product characteristics," a Pfizer spokesperson told AAP FactCheck.
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