The Covid-19 single-dose vaccine from Janssen, a pharmaceutical unit of Johnson & Johnson, is less effective against the Delta variant, according to a new study. The research examined blood samples in a laboratory that indicate the need to apply the second dose.
The study, however, has not yet been reviewed by independent researchers or published in a scientific journal. Earlier this month, Janssen published preliminary data indicating that its vaccine is effective against the Delta variant.
“The message we wanted to give was not that people shouldn’t get the J&J vaccine, but we hope that in the future it will gain potency with another dose of J&J or with Pfizer or Moderna,” the study leader told the New York Times, Nathaniel Landau, virologist at NYU’s Grossman School of Medicine.
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Initial studies indicate that the mRNA vaccines manufactured by Moderna and Pfizer are effective against the Delta variant and may provide protection for years, as long as the virus no longer mutates from its initial form.
J&J spokesman Seema Kumar told the Times that the data from the latest study “does not speak to the complete nature of immune protection.” The new strain now accounts for 83% of all covid cases in the US.
For the Centers for Disease Control and Prevention (CDC), the J&J vaccine should perform well against the Delta variant, as it does against other variants circulating in the United States.
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