The logic and challenge behind the FDA and CDC’s decision to temporarily halt the one-shot vaccine.
The US rollout of Johnson & Johnson’s single-dose Covid-19 vaccine was halted Tuesday as regulators race to investigate rare blood-clotting complications linked to the shot. The move may force thousands of people scheduled to receive the shot this week to scramble for an alternative.
Both the Food and Drug Administration and the Centers for Disease Control and Prevention recommended a pause in distributing the vaccine after six reported cases of cerebral venous sinus thrombosis (CVST). These clots block blood flowing out of the brain and can quickly turn deadly.
The complications were found in women between the ages of 18 and 48, and they arose between six and 13 days after receiving the Johnson & Johnson vaccine. “Of the clots seen in the United States, one case was fatal, and one patient is in critical condition,” said Peter Marks, the head of the FDA’s Center for Biologics Evaluation and Research, during a Tuesday press conference.
However, the fact that so few cases led to a nationwide pause of the vaccine has raised questions about a possible overreaction.
Speaking at the White House on Tuesday, Anthony Fauci, head of the National Institute of Allergy and Infectious Diseases, argued that the CDC and FDA were acting “out of an abundance of caution” and emphasized that their Tuesday decision was a “pause,” implying that it is meant to be temporary.
“I don’t think that they were pulling the trigger too quickly,” Fauci said.
But the move has nonetheless created confusion for people slated to receive the Johnson & Johnson shot and raised fears that it could fuel hesitancy around Covid-19 vaccines.
Johnson & Johnson itself was already reeling from a manufacturing error at one of its suppliers that ruined 15 million doses. And in Colorado, three mass vaccination sites stopped administering the Johnson & Johnson vaccine last week after 11 people reported feelings of nausea and dizziness.
For regulators, the episode highlights the tricky challenge of balancing caution against an urgent need for a vaccine in a still-raging pandemic. And as they investigate the problem, they also have to try to maintain public confidence in the vaccination program. The pause helps show that regulators are taking potential problems seriously, but if they botch the messaging, that could make people less likely to get vaccinated.
What is cerebral venous sinus thrombosis and how is it connected to Johnson & Johnson’s Covid-19 vaccine?
Cerebral venous sinus thrombosis is a condition that blocks blood from leaving the brain. In the general population, it occurs in about five out of a million people. Symptoms of CVST include headache, blurred vision, seizures, and a loss of control of the body.
However, there are several factors that made regulators pay close attention to the recent cases following vaccinations with the Johnson & Johnson shot. Marks explained that patients with these clots also had thrombocytopenia, a condition where platelets in the blood drop to very low levels, leading to bleeding and bruising. The combination of blood clots and low platelets means that patients cannot receive conventional blood clot therapies like heparin, a blood thinner. That’s why health officials want to wait to resume vaccinations with the Johnson & Johnson vaccine until they can investigate the concern and come up with new guidelines if necessary.
Another factor is that these cases occurred in younger women, who normally don’t face a high risk of these types of clots.Original Source
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