What You Need to Know About the Risk of Blood Clots From J&J Vaccine [Updated]

At least six of the more than 6 million people who received the Johnson & Johnson / Janssen COVID vaccine developed a rare type of blood clot. As a result, the FDA and CDC announced they would suspend the use of this vaccine. The pause is likely to last at least another week.

The initial reason for the hiatus was to allow time to educate healthcare providers across the country about this rare complication, and to allow the CDC ‘s Vaccine Practice Advisory Committee to review the evidence and decide whether to change its recommendations, according to FDA and CDC officials. about who should get the vaccine.

The committee met on April 14 and felt that they did not have enough information about the risks and benefits of the vaccine to change the recommendation or recommend that vaccination be resumed. They plan to meet again in a week – perhaps around April 21, although the meeting has not yet been scheduled – when the pause could potentially be lifted.

Meanwhile, Johnson & Johnson said in a press release that they will postpone the rollout of the vaccine in Europe (where it has been authorized but not yet in use) and that they are suspending vaccination in ongoing clinical trials that use the vaccine. vaccine.

What is a rare complication?

Six of the cases were venous sinus thrombosis , a type of stroke that occurs when a clot prevents blood from flowing out of the brain. It’s already a rare condition (2 to 14 cases per million people per year, according to the CDC), but what’s unusual is that all six people had CVST along with low platelet counts. Platelets are blood cells involved in clotting; CVST usually occurs in people with normal platelet counts.

These cases are unusual because they are associated with CVST and low platelet counts and occurred 6-13 days after Johnson & Johnson’s vaccination. They are of particular concern because the usual treatment for blood clots is the administration of anticoagulants such as heparin, but heparin can be harmful to people with CVST, which is why the FDA and CDC want healthcare providers to be aware of this rare condition and to know that they must treat it by -other. …

The first six people to report this rare vaccine-related illness were all women between the ages of 18 and 48. One case was fatal and one person is in critical condition. It is not yet known whether age, gender, or other medical conditions can predispose a person to develop this complication. We may find out more in the coming days.

At the April 14 ACIP meeting, a Janssen spokesperson noted that a 24-year-old man had a similar blood clot in September during a clinical trial and recently received a report of a thrombosis of this clot. type 59 year old woman.

Note that COVID-19 itself has a high risk of blood clots (of a different type). As noted by physician Megan Ranney on Twitter , the incidence of blood clots with COVID can be as high as 20% in hospitalized patients.

What if I just got the J&J vaccine?

If you received the vaccine a month ago or longer, your chances of developing this condition are extremely low; there are no known cases starting more than 13 days after vaccination.

If you have received the vaccine within the past few days, you do not need to worry about flu-like symptoms that follow , including headache, fatigue, and fever if they occur within the usual time frame (a few days or up to a week). after vaccination).

If you have received the vaccine within the past few weeks, seek medical attention if you develop any of the following:

  • Strong headache
  • Severe abdominal pain
  • Leg pain
  • Dyspnea

When seeking medical attention, be sure to tell your doctor that you received the Johnson & Johnson vaccine and the date when you received it. The FDA and CDC say they are conducting “aggressive advocacy” to make sure all suppliers know to keep a close eye on this rare complication.

Is this a problem with other vaccines?

There is no indication that these rare blood clots will develop in people who have received Moderna or Pfizer vaccines. To date, 121 million Americans have received at least one dose of COVID-19 vaccine, of which J&J accounts for 6-7 million. If this complication had happened with the other two vaccines, we would probably have noticed it by now. (This does not guarantee that they are completely safe, but the odds are very good.)

The AstraZeneca vaccine, however, has been linked to rare blood clots. (It is not used or licensed in the US, but other countries have noted this link .) Both AstraZeneca and J&J vaccines use an adenoviral vector. One hypothesis is that, in very rare cases, a person’s immune system may react to a carrier in such a way that it attacks the platelets in its own body. CDC consultants plan to review current and past research on these and other adenovirus vaccines to understand what’s going on.

What does “pause” mean in general?

The vaccine has not been withdrawn and is still licensed for emergency use. The pause is “a recommendation, not a mandate,” said Peter Marks, director of the FDA’s Center for Biological Evaluation and Research. If you discuss the vaccine with your doctor and the provider agrees that the benefits to you outweigh the risks, they can still give the vaccine. But for now, it is recommended to abstain.

If you have an appointment for the next week, you will most likely be asked to reschedule or be offered one of the other two available vaccines. If it’s more than a week before your visit, it’s probably best to wait and see.

How does this relate to the incidence of blood clots as a complication of contraception?

Pulmonary embolism and deep vein thrombosis (two types of blood clots that are not the same as CVST) occur in 0.3–1 % of people taking estrogen-containing oral contraceptives for 10 years. Blood clots can also occur as a result of pregnancy, so the risk of clotting with birth control pills has long been known, understood, and balanced with the other risks and benefits of taking or not using these birth control pills.

I only mention this because several people have noted on social media that the one in a million risk of blood clots from a vaccine pales in comparison to the risk we already know and in many cases take from birth control pills.

Numerically, that’s for sure. But the complication of the vaccine deserves attention because it is new, because health care providers need to know that it cannot be treated with conventional blood clot treatment, and because the risk can be completely avoided by injecting another vaccine instead.

What does this tell us about the safety of the vaccine in general?

For people who were skeptical about vaccines, news of this dire complication may seem like proof that vaccines are dangerous.

But it’s worth noting that the vaccine was suspended due to one complication in a million (or two in a million, considering that about 3 million doses were given too recently to detect a complication), and the pause came very quickly. once the regulators found out about it. Contrast this with often-circulated misinformation, which uses fictional or out-of-context stories to imply that people are dying from the vaccine all the time and nobody cares.

Suspending a vaccine to investigate a rare side effect is a sign that regulators are really paying attention and that they are transparent about the investigation.

It is also worth noting that these cases were reported to the CDC and the FDA through VAERS, a database where anyone can enter a record of health complications following vaccinations. While anti-vaccination activists often abuse this database, claiming that fatal complications are being ignored, the truth is that even these few cases of serious complications were discovered through VAERS, and regulators were quick to act to gather more information and take action. …

What happens next?

Since the complication can occur a week or two after vaccination, don’t be surprised if more cases show up in the next week or so. (“It’s too early to make any assumptions about how much,” Marx said in a news conference.)

Expect to hear more after the next ACIP meeting next week and as more information becomes available. The CDC and the FDA are likely to make an announcement when they decide it’s time to resume vaccinations, or, less likely, but still possible, if they decide the evidence supports a change in recommendation or an emergency cancellation of a vaccine approval.

Updated on April 13, 2021 at 12:18 pm to note that the risk of blood clots from COVID outweighs the risk from any vaccine, and that the AstraZeneca vaccine is not currently in use in the United States. the results of the ACIP meeting, at which the pause was extended.

More…

Leave a Reply