As part of National Dog Bite Prevention Week in the USA, the US Postal Service has released figures on dog attacks on posties.Across the USA, 5577 posties reported being bitten by dogs in 2011. The USPS has reported that these attacks cost $1.2m in medical expenses.According to statistics, between 12 and 20 people are killed each year in the USA as a result of dog bites.The USPS is working with a number of organisations, including the American Veterinary Medical Association and the Prevent The Bite campaign to raise awareness of the issue of dangerous dogs during National Dog Bite Prevention Week.The USPS stated that the safety of its employees is a top priority. Letter carriers fearing for their safety due to a loose or unrestrained pet may stop delivery and ask homeowners to pick up their mail at the post office until the pet is restrained. In cases where a carrier sees a dog roaming and can’t work out where it resides, delivery could be interrupted to the entire neighbourhood.