Individuals who have been administered the single-dose Johnson & Johnson COVID-19 vaccine may require a booster jab to tackle some of the concerning coronavirus variants, suggests a new study.

A significant proportion of blood samples taken from people who had received the J&J vaccine showed low neutralizing antibody levels against the Delta, Delta Plus, Beta and Lambda variants, noted the study posted on the medical website bioRxiv which is yet to be peer-reviewed. Neutralizing antibody levels were found to be so low that the vaccine may not provide even 50% protection against infection with these variants, stated investigators from the New York University Grossman School of Medicine.

A 50% efficacy is the least to get an emergency-use approval from the US FDA, which the J&J vaccine has received. On the basis of studies conducted with other vaccines, investigators speculate that neutralizing antibody levels in J&J vaccine recipients could be improved either with a second dose of the same vaccine or a dose of the Pfizer/BioNTech or Moderna mRNA vaccine… (Reuters, July 23, 2021)