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What you need to know about the Johnson & Johnson COVID-19 vaccine


NOTE:  The following information was published April 26, 2021. For current vaccination information, visit

Friday the Centers for Disease Control (CDC) and U.S. Food and Drug Administration (FDA) concluded their safety review of the Johnson & Johnson (Janssen) COVID-19 vaccine and determined that it is safe and effective in preventing COVID-19 saying, “the available data show that the vaccine’s known and potential benefits outweigh its known and potential risks in individuals 18 years of age and older.”

“All vaccines are monitored closely,” says Alex Benjamin, MD, LVHN Chief Infection Control and Prevention Officer. “The reporting system called VAERS was designed to flag things like this, and the fact that vaccine distribution and production was paused means the system is working.”

Vaccine Adverse Event Reporting System (VAERS)

Providers across the country have access to a reporting system called VAERS. It allows them to record health problems that occur after a person has received a vaccination. Even if providers do not think the vaccination caused the event, they should still report it.

The CDC says, “VAERS gives vaccine safety experts valuable information so they can assess possible safety concerns related to vaccines, including new COVID-19 vaccines. It is especially useful for quickly detecting unusual or unexpected patterns of health problems (also called ‘adverse events’) that might indicate a possible safety problem with a vaccine.”

The report itself does not mean that there is a connection between the vaccine and the health problem. In fact, the CDC even says, “Some reports may contain information that is incomplete, inaccurate, coincidental, or unverifiable. Most reports to VAERS are voluntary, which means they are subject to biases.”

This is why a full investigation is such a critical part of the process. As of April 12, there were six reported U.S. cases of a rare and severe type of blood clot in individuals after receiving the Johnson & Johnson (Janssen) vaccine. All six people were women ages 18 through 49 with a type of blood clot called cerebral venous sinus thrombosis (CVST) that was seen in combination with low levels of blood platelets, also known as thrombosis-thrombocytopenia syndrome (TTS). 

When the FDA and CDC halted production and distribution of the Johnson & Johnson vaccine April 13, they began a full investigation to ensure that the vaccine is safe.

“As of April 26, 15 cases have been identified out of 7,979,007 vaccine doses administered,” Benjamin says. “It is extremely rare. The CDC and FDA still did their due diligence to ensure these vaccines are safe.”

Following the review the CDC and FDA updated the Johnson & Johnson vaccine fact sheet to include information about the risk for blood clots and low levels of platelets. This fact sheet is to be distributed to all vaccine recipients and caregivers.

Vaccines at LVHN

Currently, the state of Pennsylvania is sending all shipments of Johnson & Johnson vaccine to intermediate units and retail pharmacies as part of a thoughtful plan to vaccinate prekindergarten-12 educators and staff as well as early childhood education workers. Everyone age 16 and older, including prekindergarten-12 educators and staff, can receive a Moderna or Pfizer vaccine at LVHN.

Three cases of CVST have been associated with Moderna, out of 84.7 million doses administered. All three people had normal platelet counts and began developing CVST within 12 days after vaccination. There haven’t been any reported clotting issues among people who received a Pfizer COVID-19 vaccine.

You can either schedule an appointment on your MyLVHN patient portal or call our vaccine hotline (833-584-6283) to make an appointment. The COVID-19 Vaccine Hotline is open Monday-Friday, 8:30 a.m.-5:30 p.m.

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