KEY POINTS

  • Researchers recommend giving booster shots to J&J vaccine recipients
  • Previous smaller studies have indicated that the J&J shot is highly effective against the Delta variant
  • Delta now accounts for 83% of all sequenced cases in the country 

The Janssen COVID-19 vaccine made by Johnson & Johnson is less effective against the more contagious Delta and Lambda variants, a new study has found. 

In a pre-print published on bioRxiv Tuesday, researchers suggested that people who received the single-dose J&J COVID-19 vaccine may need a shot of mRNA vaccines made by Pfizer-BioNTech or Moderna to boost protection against COVID-19 variants. 

“The message that we wanted to give was not that people shouldn’t get the J.&J. vaccine, but we hope that in the future, it will be boosted with either another dose of J.&J. or a boost with Pfizer or Moderna,” Nathaniel Landau, a virologist at N.Y.U.’s Grossman School of Medicine who led the study, said. 

The new study is consistent with previous observations which suggested that a single dose of the AstraZeneca vaccine, which uses components similar to those found in the J&J shot, is only 33% effective against the Delta variant. 

However, the pre-print contradicts smaller studies that found the single-dose J&J vaccine to be highly effective against the more contagious B.1.617.2 Delta variant even more than half a year after inoculation. 

“The coverage of the variants is going to be better than what people anticipated,” Dr. Dan Barouchm a virologist at Beth Israel Deaconess Medical Center in Boston, said in a news release, The New York Times reported. 

The Delta variant is currently the most contagious COVID-19 variant known. The variant, which was first identified in India, now accounts for 83% of all sequenced COVID-19 cases in the United States, Dr. Rochelle Walensky, Director of the Centers for Disease Control and Prevention, said Tuesday, according to CNBC

During a Senate hearing, Walensky noted that the low vaccinated rates in several U.S. counties are leading to the rapid spread of the highly contagious variant. 

On Monday, officials at Houston Methodist Hospital in Texas also reported the state’s first case of the Lambda variant. The variant, which is currently designated as a “variant of interest” was first detected in Peru where it makes up 81% of all COVID-19 cases sequenced, as reported by ABC News

It is unclear how transmissible the Lambda variant is, but experts note that it carries a number of mutations, including one that makes it evade vaccines better than other strains.

COVID-19 has so far claimed more than 4,114,260 lives and infected 191,386,140 people across the globe. The United States, the world’s worst-hit country in terms of both cases and deaths, has so far recorded 34,173,249 cases and 609,525 deaths, according to Johns Hopkins University data.

The new US FDA warning label is a further blow for Johnson & Johnson, which was granted an emergency use authorization for its shot in February 2021 but has played a minor role in America's coronavirus immunization campaign The new US FDA warning label is a further blow for Johnson & Johnson, which was granted an emergency use authorization for its shot in February 2021 but has played a minor role in America's coronavirus immunization campaign Photo: AFP / Mark RALSTON