WASHINGTON (Reuters)

President Joe Biden on Tuesday said the United States was on track to have enough vaccines for every adult in the country by the end of May.

Biden announced that Merck & Co Inc will help make rival Johnson & Johnson’s single-shot COVID-19 vaccine in a partnership that he said was similar to those seen during World War II.

With three vaccines now available, Biden said he was confident the country would reach his goal of delivering 100 million COVID-19 vaccine doses in 100 days.