In addition to adhering to a regular vaccination schedule, the virus causing the disease can be inactivated by using an appropriate solution of chlorine bleach, following the manufacturer's instructions to clean kennels and other areas where dogs congregate. The Purina Pet Care Center has used a chlorine bleach in the past with success. Currently, the Center uses an iodine-based solution. Iodine is another agent capable of destroying the virus. Because parvovirus can be spread from dog to dog via contact with infected feces or carried by shoes, clothing, carriers, food and water bowls and other objects, the Purina Pet Care Center enforces strict sanitation procedures throughout its kennels. All pens and runs are thoroughly sanitized and dried before the dogs are returned. Food and water bowls are washed daily, rinsed in a disinfectant and allowed to dry before being used again. Parvovirus can survive many weeks on contaminated surfaces. For this reason, kennel owners should exercise great caution in placing puppies where parvovirus infection has occurred. It is advisable to introduce only puppies that have been vaccinated and then only after thorough disinfection of the premises. Antibodies acquired from the mother can interfere with the development of the puppy's own immunity to parvovirus. This effect can last up to 16 weeks. It is important that puppies receive the final puppy parvovirus vaccination at 16 weeks of age or older. Sick dogs should be segregated from other dogs. Newly acquired dogs or dogs who have been at shows, field trials or other situations where they come in contact with other dogs should be kept in isolation. They should be observed for any signs of parvovirus or any other diseases before being returned to the kennel. Visitors to a kennel should be discouraged unless there is a reason for the visit. If you are showing dogs or puppies to a visitor, bring the dog or puppy to the visitor rather than bringing the visitor into the kennel.