The Centers for Disease Control and Prevention (CDC) and the Food and Drug Administration (FDA) halted the use of the Johnson & Johnson COVID-19 vaccine at federally administered sites on April 13, after six cases of blood clots found in women who used the vaccine.
The federal agencies called for a pause at state-administered vaccine sites as well.
Out of 74 million people fully vaccinated as of April 13, 9% or 6.8 million people received the Johnson & Johnson vaccine.
"Right now, these adverse events appear to be extremely rare. COVID-19 vaccine safety is a top priority for the federal government, and we take all reports of health problems following COVID-19 vaccination very seriously," the two agencies wrote in a joint statement.
In March, the Biden administration announced plans to accelerate the manufacturing and distribution of the Johnson & Johnson vaccine to around 100 million doses by the end of May. The vaccine accounts for 7% or 16.2 million of the 237.8 million total doses distributed between December 2020 and April 13. About 9.3 million doses of the Johnson & Johnson COVID-19 vaccine remain unused as of April 13. The Johnson & Johnson vaccine is the only one of the approved vaccines requiring a single dose.
So far, 16.2 million Johnson & Johnson vaccines have been distributed.
Earlier this month, up to 15 million doses of the Johnson & Johnson vaccine manufactured in a Baltimore plant were not approved for distribution because of a mix up with another vaccine. None of the vaccines administered have come from the Baltimore plant.
"People who have received the J&J vaccine who develop severe headache, abdominal pain, leg pain, or shortness of breath within three weeks after vaccination should contact their health care provider," according to the FDA and CDC statement.