Johnson & Johnson Vaccine Provides 8-Month COVID Immunity, Protection Against Delta Variant
Johnson & Johnson announced Thursday that their vaccine generated a "strong neutralizing antibody response" to the Delta COVID-19 variant, with 85% effectiveness
The Johnson & Johnson single-dose vaccine can now provide immunity against COVID-19 for at least eight months, as well as protection against "other highly prevalent SARS-CoV-2 viral variants" of the virus.
The company announced on Thursday that during its trial, the vaccine generated a "strong neutralizing antibody response" to the widely spreading Delta variant, with 85% effectiveness.
It is also expected to improve and continue immunity past the eight-month span of their study — reassuring the over 12 million Americans who have gotten the Johnson & Johnson dose.
"Current data for the eight months studied so far show that the single-shot Johnson & Johnson COVID-19 vaccine generates a strong neutralizing antibody response that does not wane; rather, we observe an improvement over time," said Mathai Mammen, global head, Janssen research & development, Johnson & Johnson, in a statement.
Never miss a story — sign up for PEOPLE's free daily newsletter to stay up-to-date on the best of what PEOPLE has to offer, from juicy celebrity news to compelling human-interest stories.
"In addition, we observe a persistent and particularly robust, durable cellular immune response," Mammen added.
The Johnson & Johnson study follows the lead of Moderna and Pfizer after the biotech companies also announced that their vaccines are extremely effective against the variant, preventing illness 90% of the time and hospitalization or severe illness 94% of the time.
The Delta variant currently makes up over 20% of all COVID-19 cases, and is present in all 50 states. Health experts are concerned the highly contagious strain will continue spreading, especially among unvaccinated people.
"The Delta variant is currently the greatest threat in the U.S. to our attempt to eliminate COVID-19," Dr. Anthony Fauci, the nation's top infectious diseases expert, said during a White House briefing last month.
RELATED VIDEO: The Importance of the COVID-19 Vaccine and the Call for "Unity"
Fauci, 80, added Tuesday that he's "very concerned" about the Delta variant spreading in under-vaccinated, high-risk areas, and said it could split the country into "two Americas": one in which the virus is circulating widely and the other with low rates because most residents are vaccinated.
"When you have such a low level of vaccination superimposed upon a variant that has a high degree of efficiency of spread, what you are going to see among under-vaccinated regions — be that states, cities or counties — you're going to see these individual types of blips," he said, CNN reported. "It's almost like it's going to be two Americas."
As of Thursday, nearly 181.4 million Americans (just below 55% of the total population) have received at least one vaccine dose and 155.9 million (47%) are fully vaccinated, according to the Centers for Disease Control.
As information about the coronavirus pandemic rapidly changes, PEOPLE is committed to providing the most recent data in our coverage. Some of the information in this story may have changed after publication. For the latest on COVID-19, readers are encouraged to use online resources from the CDC, WHO and local public health departments. PEOPLE has partnered with GoFundMe to raise money for the COVID-19 Relief Fund, a GoFundMe.org fundraiser to support everything from frontline responders to families in need, as well as organizations helping communities. For more information or to donate, click here.