Transplacental infection results in congenital infection of puppies which is the most typical presentation of the disease. More than one puppy in a litter may be affected, although this may not occur simultaneously. Successive litters can be affected, therefore a dam whelping an infected litter should not be allowed to breed again. | Transplacental infection results in congenital infection of puppies which is the most typical presentation of the disease. More than one puppy in a litter may be affected, although this may not occur simultaneously. Successive litters can be affected, therefore a dam whelping an infected litter should not be allowed to breed again. |