US recommends 'pause' for JJ vaccine over clot reports

The U.S. is recommending a ``pause'' in administration of the single-dose Johnson Johnson COVID-19 vaccine to investigate reports of potentially dangerous blood clots.

In a joint statement Tuesday, the Centers for Disease Control and Prevention and the Food and Drug Administration said they were investigating clots in six women that occurred in the days after vaccination. The clots were observed along with reduced platelet counts _ making the usual treatment for blood clots, the blood thinner heparin, potentially ``dangerous.''

More than 6.8 million doses of the JJ vaccine have been administered in the U.S., the vast majority with no or mild side effects.

U.S. federal distribution channels, including mass vaccination sites, will pause the use of the JJ shot, and states and other providers are expected to follow. The other two authorized vaccines, from Moderna and Pfizer, are not affected by the pause.

CDC's Advisory Committee on Immunization Practices will meet Wednesday to discuss the cases and the FDA has also launched an investigation into the cause of the clots and low platelet counts.

``Until that process is complete, we are recommending a pause in the use of this vaccine out of an abundance of caution,'' Dr. Anne Schuchat, Principal Deputy Director of the CDC and Dr. Peter Marks, director of the FDA's Center for Biologics Evaluation and Research said in a joint statement.

They are recommending that people who were given the JJ vaccine who are experiencing severe headache, abdominal pain, leg pain, or shortness of breath within three weeks after receiving the shot contact their health care provider.

Officials say they also want to educate vaccine providers and health professionals about the ``unique treatment'' required for this type of clot.

The JJ vaccine received emergency use authorization from the FDA in late February with great fanfare, with hopes that its single-dose and relatively simple storage requirements would speed vaccinations across the country. Yet the shot only makes up a small fraction of the doses administered in the U.S. as JJ has been plagued by production delays and manufacturing errors at the Baltimore plant of a contractor. (AP)