NEW YORK—U.S. health officials Monday announced a one-year ban on bringing in dogs from more than 100 countries where rabies is still a problem. Dogs coming in from those countries already needed proof of rabies vaccination. The ban is being imposed because of a spike in the number of puppies denied entry because they weren’t old enough to be fully vaccinated, the Centers for Disease Control and Prevention said. The ban goes into effect July 14. The ban applies to dogs coming into or returning to the country, including pets or those brought in for sale or adoption. For example, if an American couple took their dog to Belize, they wouldn’t be able to bring the dog back to the United States unless the dog first spends six months in a country that is not at a high risk for rabies. About 1 million dogs are brought into the United …