Ebola vaccines can’t shed deadly virus

After health care workers at a Denver hospital received an Ebola vaccine in November, social media users spread a baseless claim that vaccine shedding puts other people at risk of catching the often-fatal disease.

"US Hospitals Caught Injecting Experimental Ebola Vaccine That Sheds!" read the caption on a Jan. 22 Instagram post. "Colorado is conducting an experimental Ebola vaccine program which has been found to shed 31% of the time."

The post shared an excerpt from a longer interview with Dr. Richard Bartlett on Alex Jones’ InfoWars show, which is known for sharing conspiracy theories and misinformation. Early in the COVID-19 pandemic, Bartlett pushed the unproven theory that budesonide, a steroid in asthma inhalers, can cure COVID-19.

In the full interview that Jones shared on X, Bartlett and Jones discussed the news about Denver health care workers being among the first in the U.S. to receive an Ebola vaccine to prepare for a potential future Ebola outbreak.

Bartlett said people receiving the Ebola vaccine can expose people to the live Ebola virus. In the longer interview, Bartlett said the vaccine sheds 31% of the time, meaning in those instances, the Ebola virus could be transmitted to someone else.

The Instagram post was flagged as part of Facebook’s efforts to combat false news and misinformation on its News Feed. (Read more about our partnership with Facebook.)

The Ebola vaccine is neither experimental, nor sheds Ebola virus, health authorities told PolitiFact. And despite other claims in the video, there’s no threat of an Ebola outbreak from a planned bat research center at Colorado State University, where scientists will research how bats respond to infectious diseases. 

The lab will not be handling dangerous pathogens such as Ebola, the school’s website said.

Ebola is an often-fatal virus that causes severe inflammation and tissue damage throughout the body.

Of four species of Ebola viruses that can infect humans, Ebola virus species Zaire ebolavirus is the deadliest, with fatality rates of 70% to 90% if left untreated, the CDC said.

That strain is responsible for most recorded Ebola disease outbreaks. 

The virus is spread through direct contact with blood and bodily fluids of an infected person or by touching items contaminated with those fluids.

Merck makes Ervebo, which is the first Ebola vaccine approved by the U.S. Food and Drug Administration.

In 2019, the vaccine was approved in the U.S. for use in people ages 18 and older. In July 2023, approval was expanded for children 1 year and older.

The European Medicines Agency in 2019 conditionally approved Ervebo for adults and gave full authorization in 2021. It expanded the vaccine’s use to children in September 2023.

The vaccine is also approved in the United Kingdom, Canada, Switzerland and 10 countries in Africa. It protects only against Zaire ebolavirus, not the other strains that can infect humans. 

The Ervebo vaccine does not contain the Ebola virus. Instead, it uses a different type of virus, vesicular stomatitis, that has been weakened and modified to contain a protein from the Zaire ebolavirus.

Health authorities told PolitiFact it’s impossible to catch Ebola from vaccine shedding because the vaccine does not contain the Ebola virus. The vesicular stomatitis virus that the vaccine is made with can shed — one study showed that it shed in 31% of children, peaking at about a week after vaccination — but that can’t cause Ebola, authorities said.

The vesicular stomatitis virus "has little to no effect on humans," said Anna-Sofia Joro, a European Medicines Agency spokesperson.

The vesicular stomatitis virus has been detected in blood, saliva, urine and fluid from blisters of vaccinated people. The package insert for Ervebo said shedding has been detected for up to 14 days after vaccination. The duration of shedding is unknown, but samples taken 28 days after vaccination tested negative, the insert said. 

"Vaccination with Ervebo cannot cause Ebola because there is no risk of shedding Ebola virus," said David Daigle, a CDC spokesperson.

The FDA also said in a statement to PolitiFact that it’s "not possible to get Ebola infection from shed vaccine virus."

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In the clip shared on Instagram, Bartlett suggested a connection between the vaccines and the bat research center at Colorado State University. 

We found numerous social media posts baselessly connecting the Ebola vaccines given in Denver and the bat research center.

In 2021, Colorado State University received a $6.7 million grant from the National Institutes for Health to expand its existing bat research program.

Researchers at the school have studied bats for 15 years and infectious diseases for six decades. The new lab will study only low-risk pathogens, "comparable to organisms that cause food-borne illness or strep throat," the school said.  

The Ebola vaccine is not commercially available in the U.S. Daigle said the only people authorized to receive it in the U.S. fall into three occupational categories: responders to an Ebola outbreak; lab staff at certain facilities that may handle Ebola specimens; and health care workers at designated Special Pathogen Treatment Centers, involved in treating or transporting Ebola patients.

The Denver health care workers who received the vaccine are in the third category.

Denver Health was designated in 2015 as one of 13 Regional Emerging Special Pathogens Treatment Centers by the U.S. Department of Health and Humans Services, serving as a care site for patients with special pathogens. 

After a 2014 Ebola outbreak that reached the U.S., Denver Health created a high-risk infection team of nurses, doctors, paramedics and other workers to prepare to handle outbreaks of special pathogens. 

Denver Health said in a statement to PolitiFact that nine of its employees on the high-risk infection team received the Ebola vaccine. None reported any significant side effects, and there are no plans to further vaccinate Denver Health staff, it said.

An Instagram post claimed that U.S. hospitals were caught injecting an experimental Ebola vaccine that sheds.

The Ebola vaccine is not experimental; it’s been FDA-approved for use in the U.S. since 2019. The vaccine does not shed the Ebola virus because it doesn’t contain the Ebola virus. It’s made with a different virus, vesicular stomatitis, that has been weakened and modified to contain a protein from the Zaire ebolavirus. 

Vesicular stomatitis virus can shed, but it’s harmless, officials said. 

We rate the claim False.