By Eric Sylvers 

Europe's health agency said a warning should be added to the product information of the Johnson & Johnson Covid-19 vaccine that unusual blood clots are a very rare possible side effect, but that the benefits of taking the shot outweigh the risks.

The European Medicines Agency said on Tuesday that it had looked at data from the U.S., where there have been eight reported cases of people suffering from rare blood clots coupled with a low level of platelets after they received the J&J vaccine. One of those people died. More than seven million people have received the vaccine in the U.S.

Last week, U.S. health authorities recommended pausing the rollout out of the vaccine. They had considered only issuing a warning, but decided a pause would help make doctors aware of how to treat the rare condition. J&J then followed with the decision to pre-emptively pause the rollout in Europe, which had just begun.

The eight cases in the U.S. were similar to those that have occurred with the AstraZeneca PLC vaccine in Europe, something that EMA said it took into consideration in making its recommendation. The two vaccines use similar technology.

In the U.K., where 20.6 million people had received at least one dose of the AstraZeneca vaccine by April 5, there has been about one case of the unusual clotting with low platelets for every 200,000 shots given. There have been 22 deaths out of 99 cases. The majority of cases and deaths have been in women under 60 years old, prompting many countries to restrict the use of the vaccine to older recipients.

Write to Eric Sylvers at eric.sylvers@wsj.com

 

(END) Dow Jones Newswires

April 20, 2021 11:35 ET (15:35 GMT)

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