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Photos of blood clots removed during embalming show no link to COVID-19 vaccines; the risk of blood clotting is much higher after COVID-19 than vaccination


COVID-19 vaccines are linked to an increase in abnormal blood clots seen by embalmers


Inadequate support: Abnormal blood clotting can have many causes unrelated to COVID-19 vaccines, for example an underlying medical condition or COVID-19 itself, which is a more likely cause of blood clotting than vaccination. Blood clotting also occurs after death. Without pathology analysis, photos of clots do not provide enough evidence to suggest that these clots are neither abnormal nor related to vaccination.


COVID-19 mRNA vaccines are those primarily used in many countries, including the United States. These vaccines have not been associated with a higher risk of blood clotting. While some COVID-19 vaccines have been linked to a severe form of blood clotting with low platelet counts, such cases are very rare. COVID-19 increases the risk of blood clots and other cardiovascular complications much more than vaccination.

COMPLETE CLAIM: COVID-19 vaccines are linked to an increase in abnormal blood clots seen by embalmers


On October 23 and 24, 2022, Canadian news site Western Standard writer Matthew Horwood posted two tweets showing pictures of blood clots. One of the tweets included quotes claiming, “These are just not normal clots. It’s almost like it’s tissue, not a blood clot” and “Before, only 10-15% clotted. Now I am lucky to have bodies that are not clotted”. Screenshots of that tweet went viral on Instagram (see examples here and here), receiving more than 34,000 interactions, according to social media analytics tool CrowdTangle.

The other tweet contained several photos, including one that had previously been published in an article by The Epoch Times, a website that had previously published misinformation about COVID-19 vaccines. The article attributed the photo to Richard Hirschman, an embalmer who claimed to have found “strange clots” in people who have died since the rollout of COVID-19 vaccines. After the article was published, Health Feedback reviewed Hirschman’s claim and found no scientific evidence to support an association between these clots and COVID-19 vaccines.

These two tweets received over 60,000 total likes and were retweeted over 29,000 times. In the following days, Horwood called on embalmers in Canada who “saw something similar” to contact him. He also continued to tweet about abnormal blood clots, genocidepeople “will probably drop dead” of these clots, and “Canadians hurt by vaxxx”.

This series of tweets – combined with the fact that a photo used by Horwood was from an Epoch Times article alleging that COVID-19 vaccines cause blood clots – communicated that the presence of blood clots in corpses was associated with vaccines. COVID-19.

This is also how some Twitter users interpreted Horwood’s tweets, based on comments like “Long covid is vax side effects” or “This vaxx was designed to spread and I know getting rid of it is one thing”. On October 27, 2022, Horwood explicitly linked clots to vaccination by Tweeter“All the embalmers I’ve spoken to have barely seen any COVID deaths in 2020. It wasn’t until after the _ rolled out that they saw them.”

This is not the first time such a claim has been made. In fact, the claim that COVID-19 vaccines caused abnormal clots in corpses based on anecdotal reports from embalmers began circulating in late 2021 and spread through individuals such as Jane Ruby and Mike Adams. However, several organizations, including Health Feedback, AFP and PolitiFact, have found this claim to be unsubstantiated. As we’ll explain below, the photos of Horwood’s tweets provide no new evidence to support such an association.

Cases of blood clots following vaccination against COVID-19 are very rare

According to estimates by the United States Centers for Disease Control and Prevention, blood clots in the deep veins of the body affect approximately 900,000 people, causing up to 100,000 deaths in the United States each year. This condition is known as venous thromboembolism (VTE). Although anyone can develop a VTE, lifestyle factors can significantly increase the risk, such as obesity, physical inactivity, and smoking.

In very rare cases, COVID-19 viral vector vaccines (Oxford-AstraZeneca and Johnson & Johnson) have been associated with a severe form of blood clotting called thrombosis with thrombocytopenia syndrome (TTS). However, the risk of TTS after vaccination with the Johnson & Johnson vaccine is very low for most people, at about four cases per million doses. The Oxford-AstraZeneca vaccine is not licensed in the United States, where most of the claims originate. Therefore, these rare cases would not explain the sharp increase in blood clots that some embalmers claimed to have observed.

Additionally, the Johnson & Johnson vaccine represents only a small fraction of total vaccinations in the United States, as the vast majority of doses administered in this country are mRNA vaccines (Figure 1). Although some have made claims linking blood clotting to mRNA vaccines, these claims are unsubstantiated. Unlike COVID-19 vector vaccines, several studies have shown that mRNA vaccines are not associated with a higher risk of blood clots[1,2]. In fact, mRNA vaccines can actually reduce the likelihood of clotting by preventing severe COVID-19, which is a major risk of developing blood clots.[3].

Figure 1. Number of COVID-19 vaccine doses administered in the United States by vaccine manufacturer between January 2021 and October 2022. Data is for individual doses, including boosters. Source: Our World in Data.

Therefore, current data contradicts the claim that COVID-19 vaccines cause increased blood clotting in the general population. While blood clots after vaccination with a viral vector vaccine are very rare, mRNA vaccines are not associated with a higher risk of clotting.

Photos of blood clots of unknown origin are insufficient to draw conclusions about the nature of the clots

Claims linking abnormal blood clots to COVID-19 vaccines are mostly based on anecdotes of embalmers who allegedly removed these clots from corpses. However, there is no verifiable information on when and how these samples were collected. Also, it is important to keep in mind that embalming is different from performing an autopsy.

Embalming is used to preserve bodies and prevent them from decomposing. But embalmers do not take or analyze biological samples and generally do not have clinical information about the bodies they handle.

In contrast, an autopsy is a surgical procedure that aims to determine the cause and manner of death. The professional performing this procedure is a pathologist, a physician trained to perform autopsies and collect medical evidence. Taking into account the clinical history of the person, the pathologist examines in detail the body and body tissues of the deceased persons and orders the necessary laboratory analyzes. Based on this evidence, the pathologist can draw conclusions about why the person died.

Nikolaus Klupp, associate professor of forensic medicine at the Medical University of Vienna, told Health Feedback in an earlier review that without histological examination of the clots, “any conclusion would be unreliable.” Indeed, given the complexity of anatomopathological examinations, it is clear that the simple observation of a blood clot is insufficient to determine its origin and its role in the death of the person.

In fact, Klupp added that some of the blood clots looked “more like post-mortem clots to him, mainly because of the color, the shape and especially the amount.” Monica Torres, a licensed embalmer in the US state of Arizona, also told AFP that “blood clots are from refrigeration”, meaning they formed after death. “It happens to a lot of bodies,” she explained. Due to the large number of bodies to be processed, many “were left in the refrigerator for long periods of time to get blood clots”.

COVID-19 is much more likely to cause blood clotting than vaccination

A spokesperson for the U.S. National Funeral Directors Association told PolitiFact that some embalmers have indeed noticed an increase in blood clots in COVID-19-related deaths. But contrary to claims, the clots appeared in both vaccinated and unvaccinated people. Torres also told PolitiFact that blood clots were present in people who died of COVID-19 “long before vaccines were available.”

Since the very beginning of the pandemic, researchers have observed that COVID-19 increases the risk of VTE, especially in patients with severe disease[4]. Subsequent research has shown that patients with moderate and even mild COVID-19 are also at higher risk of blood clots compared to the general population.[5,6]. Moreover, this risk may remain high for up to a year after infection.[7].

Johns Hopkins Medicine experts explained that clots linked to COVID-19 mainly form in the lungs and large blood vessels in the legs. However, they can also affect other organs, such as the brain and kidneys, leading to stroke and kidney failure. Additionally, damage to small skin vessels has been linked to rashes and so-called COVID toe, a condition that causes swelling and discoloration of one or more toes or fingers.

As of October 2022, SARS-CoV-2 has caused more than 6.5 million deaths worldwide, including more than 1 million in the United States. Given the large number of cases and the well-established effects of COVID-19 on blood clotting, COVID-19 itself is a much more likely culprit for any possible increase in blood clots than vaccination.

Indeed, several studies show that the risk of blood clots following vaccination is much lower than after COVID-19 itself.[8,9]. Therefore, the claim that the observed blood clots are due to COVID-19 vaccines rather than other more plausible causes, such as COVID-19, is without merit.


Photos of blood clots removed during embalming are not sufficient evidence to determine how a clot formed and what role it played in a person’s death. No evidence points to an association between the alleged increase in blood clots in cadavers and COVID-19 vaccines. Instead, many experts have pointed to COVID-19 itself or the refrigeration of bodies as a more likely cause of the observed clots.