US calls for pause of J&J shot due to blood clotting

[WASHINGTON] US health officials called for an immediate pause in using Johnson & Johnson's single-dose Covid-19 vaccine after six women who received it developed a rare and severe form of blood clotting.

The decision comes at a crucial juncture in the US vaccination effort, which has gained speed in recent weeks at the same time a worsening outbreak driven by coronavirus variants grips the upper Midwest. And it is likely to heighten worry about vaccines around the world after similar issues caused delays in distribution of AstraZeneca Plc's shot.

A type of brain blood clot called cerebral venous sinus thrombosis was seen with low levels of blood platelets in the women, who were all between the ages of 18 and 48, the US Centers for Disease Control and Prevention and Food and Drug Administration said on Tuesday in a joint statement.

"We are recommending a pause in the use of this vaccine out of an abundance of caution," the CDC and the FDA said in the statement. "This is important, in part, to ensure that the health care provider community is aware of the potential for these adverse events and can plan for proper recognition and management due to the unique treatment required with this type of blood clot." More than 6.8 million doses of the J&J vaccine have been administered in the US through Monday, the agencies said.

J&J said in a statement that it's decided to delay the rollout of its vaccine in Europe. Walgreens Boots Alliance and CVS Health., which have been administering the shot in drugstores, each said they would pause immediately. J&J fell as much as 3.2 per cent as of 9.34 am in New York, its biggest loss since Jan 29.

The Biden administration has been seeking to accelerate vaccinations in recent weeks as new coronavirus variants heighten the risk that the pandemic could drag on. White House Covid-19 response coordinator Jeff Zients said that the pause "will not have a significant impact on our vaccination plan." The prospect that the pause could disrupt the US economic recovery weighed on financial markets on Tuesday. The Dow Jones Industrial Average fell 0.3 per cent.

The decision could increase vaccine hesitancy, which is seen as a significant obstacle for health policy makers as they attempt to broaden immunisations. The J&J shot has been popular due to its single dose - vaccines made by Pfizer-BioNTech SE and Moderna require two doses spaced several weeks apart.

Many of the J&J doses in the US have been targeted to harder-to-reach populations through the federal government's distribution programme that targets pharmacies, federally qualified health centres and other locations.

The CDC will convene a meeting Wednesday of its Advisory Committee on Immunisation Practices to review the cases and assess their potential significance. The FDA will review the CDC assessment as it also investigates these cases, according to the statement.

The recommended pause may also further complicate the global vaccination push, coming just weeks after a vaccine relying on a similar approach and developed by AstraZeneca and the University of Oxford raised similar concerns in Europe. Clotting fears have prompted many countries to impose age restrictions on use of the Astra vaccine, which was co-developed with the University of Oxford.

BLOOMBERG