WASHINGTON (AP) — A vaccine to shield Americans from becoming infected with the coronavirus is emerging as the latest flashpoint in the race for the White House. President Donald Trump is accusing Democrats of “disparaging” a vaccine he repeatedly has said could be available by the end of October. Trump leveled the accusation Monday. a day after the Democratic vice presidential candidate, Sen. Kamala Harris, said she would trust public health experts and scientists over Trump. Trump is aiming to have 300 million doses of a coronavirus vaccine in stock by January under a program he calls “Operation Warp Speed” that is working to accelerate development.