Johnson & Johnson’s vaccine is cleared in Europe but there has been little delivery yet. (drawing) – JUSTIN TALLIS / AFP
One person has died of blood thrombosis and another is in critical condition in the United States after receiving the Johnson & Johnson vaccine against Covid-19, an official from the United States Medicines Agency (FDA ). To investigate the appearance of serious cases of blood clots in several people in the United States who have received the vaccine against the Johnson & Johnson coronavirus, the American health authorities recommended, on Tuesday, “a pause” in the use of the serum.
The US Medicines Agency (FDA) “is investigating six reported cases in the United States of people who developed severe cases of blood clots after receiving the vaccine,” she said in a report. communicated.
A “precautionary principle”
The US Centers for Disease Control and Prevention (CDC), the country’s main federal public health agency, will meet on Wednesday to assess these different cases. The US drug agency will then review their findings. “As long as this procedure is in progress, we recommend a pause”, affirmed the FDA, specifying to act “for the sake of precaution”. The American drug agency had however affirmed last Friday not to have established a causal link at this stage between the formation of blood clots and the injection of the vaccine against the Covid-19 of Johnson & Johnson.
In the reported cases, the scientists observed a cerebral venous thrombosis, that is to say the obstruction by a clot of one or more cerebral venous sinuses, in association with low levels of platelets in the blood, underlines the institution. The six people affected by these serious thromboembolic events are women between the ages of 18 and 48, and their symptoms appeared 6 to 13 days after the injection. Treatments usually used to treat blood clots, such as heparin, can be dangerous when it comes to the types of clots detected by the FDA that therefore require alternative treatment, warn US health authorities.
” Extremely rare “
More than 6.8 million doses of the Johnson & Johnson anti-Covid vaccine have already been administered in the United States and this type of serious side effect appears to be “extremely rare” for the moment, the FDA said. Many people in the United States who were to receive an injection of the Johnson & Johnson serum began to receive messages as early as Tuesday morning canceling their vaccination appointment. The announcement comes as the European Medicines Agency (EMA) said last week it is also investigating links between the “J & J” vaccine and cases of blood clots.
Johnson & Johnson’s single-dose vaccine was urgently authorized in the United States at the end of February, after two-dose vaccines from Pfizer / BioNTech and Moderna. It has been shown to be 66% effective in preventing moderate to severe forms of Covid-19, according to clinical trials conducted on approximately 40,000 people aged 18 or over in several countries around the world. A “viral vector”, the serum of “J & J” uses as a carrier another low virulent virus, transformed to add genetic instructions from a part of the virus responsible for Covid-19. Once in the cells, a protein typical of SARS-CoV-2 is produced, educating the immune system to recognize it.