A one-shot COVID-19 vaccine from Johnson & Johnson may be less effective against emerging forms of the coronavirus, a study suggests.
Researchers at New York University’s Grossman School of Medicine came to the conclusion after laboratory testing blood samples from volunteers.
Lead researcher Nathaniel Landau said the Johnson & Johnson vaccine does not provide the same protection against variants, such as the two-dose Pfizer or Moderna vaccines, which were developed differently using the messenger RNA method.
The study, posted online Tuesday, has neither been peer reviewed nor published in any scientific journal, and does not reflect the vaccine’s real-world effects. But the findings are similar to those of other studies showing that single-dose vaccines such as Johnson & Johnson and AstraZeneca do not produce enough antibodies to fight the delta and lambda coronavirus variants.
The delta variant, which was first detected in India, reportedly spreads more easily than other iterations of the virus. The US Centers for Disease Control and Prevention said Delta now accounts for 83% of new cases in the country.
Johnson & Johnson recently published a study showing that a single dose of its vaccine is effective against the delta variant for up to eight months.
But Landau says the NYU study results reinforce the growing theory that a follow-up shot of the Johnson & Johnson vaccine is necessary.
The Johnson & Johnson vaccine has been plagued with problems since it was approved by the Food and Drug Administration. The vaccine has been linked to a rare but serious blood-clotting disorder, as well as a rare neurological condition. Millions of doses were wasted earlier this year when a manufacturing plant in Baltimore mixed the Johnson & Johnson vaccine with ingredients from the AstraZeneca vaccine.
Johns Hopkins Coronavirus Resource Center reported that there are a total of 191.4 million COVID-19 infections in the world, including 4.1 million global deaths as of Wednesday.
South Korean health officials on Wednesday reported a new single-day record of 1,784 new COVID-19 infections, as the country struggles to contain a wave of infections linked to the delta variant, the last two weeks. More than 1,000 new cases have been registered each day.
The surge has mainly centered in the capital, Seoul, which has been placed under a variety of restrictions and has reported more cases outside the city.
South Korea has reported a total of 182,265 coronavirus cases, including 2,060 deaths. Only 32% of the country’s 52 million people have received at least one dose of the COVID-19 vaccine, with 6.6 million people fully vaccinated.
Health officials are also dealing with an outbreak aboard a naval warship that is patrolling waters off the coast of Africa that has sickened at least 270 crew.
(Some information for this report has been obtained from The Associated Press and Reuters.)