Johnson & Johnson one-dose vaccine works well against delta variant

Johnson & Johnson’s Covid-19 vaccine works well against the delta variant and the immune response lasts at least eight months, the company said Thursday, citing lab tests of vaccine recipients’ blood.

“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,” Dr. Mathai Mammen, global head of Janssen Research & Development, Johnson & Johnson, said in a news release. “Rather, we observe an improvement over time.”

The report comes as some people who have received the one-dose vaccine have wondered whether they’d need a booster against the highly contagious, mutated virus. The delta variant, which was first identified in India, now accounts for 25 percent of new Covid-19 cases in the United States and has been detected in all 50 states.