Types

• The distemper virus is highly contagious. It is fatal to 80 percent of puppies and about 50 percent of adult dogs. Canine adenovirus-1 causes hepatitis and primarily damages the liver. Although the majority of dogs survive hepatitis, it can kill susceptible dogs within two days. Parvovirus, like distemper, is highly contagious. It is more likely to be fatal to puppies than in adult dogs. Parainfluenza is an upper respiratory disease. It is rarely fatal unless it causes a secondary condition, such as pneumonia.
  
  

History

• According to the University of Idaho Veterinary College, it's not clear when the first DHPP vaccine came on the market. A vaccine for distemper was first developed in the 1940s, and it wasn't until the 1980s that an effective vaccine for parvovirus was made. Nowadays, there are several formulations of the DHPP vaccine, some including additional vaccinations or different strains of the viruses.
  
  

Considerations

• The common DHLPP vaccine combination also contains the leptospirosis vaccine. However, it is not safe for puppies and is more likely than other vaccines to cause severe, sometimes fatal, vaccine reactions. It's often only recommended if your dog lives in, or frequently visits, an endemic (high risk) area. Indiana's Purdue University Veterinary School recommends the addition of the leptospirosis vaccine because Indiana is considered an endemic area, but California's Mar Vista Animal Medical Center notes that the vaccine will not prevent dogs from becoming carriers and recommends that leptospirosis be "left out of the mix" if there is a chance the dog may have a vaccine reaction.
  
  

Time Frame

• The American Animal Hospital Association's revised 2006 vaccination guidelines are complex, but they recommend working with your veterinarian and only giving vaccinations that are necessary based on your dog's risk factors. Puppies should typically get a parvovirus vaccination at 5 or 6 weeks of age. The combination DHPP vaccine is given at 6, 9, 12 and 15 weeks. Healthy adult dogs typically don't require annual DHPP boosters, states the AAHA.
  
  

Warning

• Mild vaccine reactions are not uncommon. The AAHA lists several reactions to DHPP vaccines, including swelling, hair loss or an abscess at the location of the shot, lameness, lethargy and respiratory distress. These reactions can occur immediately or several hours after the vaccination was administered. Let your vet know of any unusual changes or reactions so that she can report it as an adverse event. Most vaccine reactions are temporary. Severe reactions, including death, are relatively rare.