LONDON (AP) — AstraZeneca says that its COVID-19 vaccine provided strong protection among all adults in a long-anticipated U.S. study. The results raised hopes that the findings could help rebuild public confidence in the beleaguered shot in other countries and were a step toward clearance for American use. AstraZeneca said Monday the vaccine was 79% effective overall at preventing symptomatic cases of COVID-19 — including in older people — and that none of the study volunteers who were vaccinated were hospitalized or developed severe disease. The company also said its experts did not identify any safety concerns related to the vaccine, including finding no increased risk of rare blood clots identified in Europe.