After the distrust of AstraZeneca, which causes rare cases of pulmonary embolism, was it time for Janssen to be avoided by the French population? The question is asked after a French study revealed that the protection of the single-dose anti-covid vaccine would be insufficient.
The survey was carried out by the pharmacovigilance centers of Lyon and Grenoble and published by the National Medicines Safety Agency this Tuesday (14). The report signals an “important number of cases of vaccine failure” of the immunizer from Johnson & Johnson, mainly against the delta variant.
With the data available so far, it is not possible to confirm the long-term efficacy of this vaccine.
From 9 July to 26 August, the two French pharmacovigilance centers were tasked with monitoring Janssen’s side effects. The data collected detail the role that the immunizing agent had, or not, in the appearance of various symptoms, more or less severe, such as thrombosis, facial paralysis, stroke and seizures, among others.
On this point, the balance is positive. “These side effects are isolated, they do not indicate a determinant role of the anti-covid vaccine and, until now, there is no direct relationship between Janssen and cases of deaths registered in the country”, points out the document.
High number of people vaccinated with Janssen in the ICUs
But given the high number of people who took the single-dose vaccine and were later admitted to ICUs with Covid-19, the French agency points out a potential risk of failure in the immunizer. The report emphasizes that these patients suffer or were suffering from severe comorbidities. They were hospitalized more than 21 days after being vaccinated. New investigations are ongoing.
The large proportion of people who received Janssen and yet contracted the coronavirus and required intensive care is alarming. In Marseille, among the seven fully vaccinated patients who were admitted to the resuscitation service during the period of the research, four received the immunizing agent from Johnson&Jonhson. In Tours, this proportion was three out of six inpatients.
By the end of August, one million doses of Janssen vaccine had been administered in France. Among people who received the single injection, 32 cases of Covid-19 were reported, representing a rate of 3.78 per 100,000. Among those infected, 29 developed severe cases of the disease, and four died. The victims were 73 to 87 years old.
Health authorities are unaware of the variant responsible for the contamination in about half of the cases, but of the 17 known cases, all were caused by the delta variant.
Janssen offers the advantage of having a single dose, but since late August, the High Health Authority of France has recommended that people vaccinated with the Johnson&Jonhson product receive a second dose of a messenger RNA-based immunizer, that is, from Pfizer or Moderna. The recommendation was accepted by the French Ministry of Health.
The infectious diseases specialist Benjamin Davido, heard by the newspaper le Parisien, considers that the case of Janssen is nothing exceptional. “There is no vaccine or miraculous treatment that provides long-term immunity against colds or contamination by the coronavirus family,” recalls the expert.