MARSHFIELD – Marshfield Clinic Health System will resume issuing the Janssen (Johnson & Johnson) COVID-19 vaccine at limited sites this week after the Food and Drug Administration and Centers for Disease Control and Prevention lifted the recommended pause following a thorough safety review, the health system announced this week.

The CDC Advisory Committee on Immunization Practices reviewed the evidence and concluded that the benefits greatly outweigh the risks of the Janssen vaccine, according to Marshfield Clinic. A CDC review of benefits and risks found that resuming use of the Janssen vaccine will prevent an estimated 800 to 3,500 intensive care unit admissions and 600 to 1,400 deaths due to COVID-19 over six months. The Janssen vaccine is given as a single dose, and it is highly effective against serious COVID-19 illness and variant strains of the virus.

The CDC and FDA recommended the U.S. pause the use of the Janssen COVID-19 vaccine April 13 to investigate six reported U.S. cases of rare and severe blood clots. The CDC and FDA have now found 15 U.S. cases in women between the ages of 18 and 59. These women experienced symptoms 1 to 2 weeks after receiving the Janssen COVID-19 vaccine. The chance of having this occur is remote.

These women experienced a rare combination of a blood clot with low platelet counts. This new syndrome is called TTS (thrombotic thrombocytopenic syndrome). It is rare, but serious and potentially life-threatening. TTS requires different treatment than what is usually given for blood clots.

The typical treatment for blood clots is heparin, which helps the body prevent blood clots and helps the body break down existing clots. However, for patients with low platelet counts, use of heparin can cause internal bleeding. The CDC and FDA paused the use of the COVID-19 vaccine to help doctors identify these specific cases so they can treat these patients correctly.

The chance of a woman between the ages of 18 and 49 getting a blood clot after receiving the Janssen COVID-19 vaccine is very rare – less than seven women in a million. The risk is about one case per million among women 50 and older, according to the CDC.

FDA has added a warning about the risk of TTS in Janssen vaccine recipients. Other COVID-19 vaccines are available for women who are concerned about this risk.

The CDC monitors for severe vaccine side effects through the Vaccine Adverse Event Reporting System, one of many reporting systems that tracks the safety of the COVID-19 vaccines.

If you develop shortness of breath, chest pain, leg swelling, persistent abdominal pain, severe headaches, blurred vision, easy bruising or tiny blood spots under the skin up to three weeks after receiving the Janssen COVID-19 vaccine, you should seek care immediately. If you have received the Janssen COVID-19 vaccine and would like additional information, call Marshfield Clinic’s COVID-19 hotline at 877-998-0880.