Taken from: http://www.angelfire.com/tn/animacules/dogs.html

Canine Distemper-This is a virus, often fatal, in dogs and puppies. The virus affects the nervous system, causing the dog to be very weak and uncoordinated. It is spread from dog to dog by respiratory secretions and aerosol exposure. Signs of this disease include fever, nasal and eye discharge, coughing, vomiting, diarrhea, and seizures. All dogs should be vaccinated against this disease. Puppies are vaccinated at 2,3, and 4 months of age, with annual boosters. This vaccine is given in combination with vaccines against several other diseases. The total vaccine is abbreviated DHLPP. Other vaccines included in this are those against hepatitis, leptospirosis, parainfluenza, and parvovirus.

Canine Leptospirosis-This is an infection caused by bacteria. It can lead to permanent kidney damage. It is a rare disease, but is easily spread to other animals, including humans. It can be transmitted by direct contact with infected urine or ingestion of infected meat. As mentioned before, the vaccine comes in combination with the distemper vaccine. However, puppies 12 weeks or younger should not get a vaccine containing leptospirosis. It is best to wait until the puppies are older and better able to handle this vaccine. The DHLPP vaccine can also be given as just a DHPP vaccine when the puppies are younger than 12 weeks.

Canine Parvovirus-This is a dangerous virus for puppies especially. It causes severe dehydration because of diarrhea, sometimes containing blood. Other symptoms include fever, inactivity, abdominal pain, and vomiting. It is also infectious, so if you suspect your dog or puppy has this disease, take them to the vet immediately so they can be properly cared for and isolated from other dogs. A vaccine is available in the DHLPP combination.

Canine Adenovirus-There are 2 types of this virus: type 1 and type 2. They cause infectious hepatitis and respiratory infection, respectively. Hepatitis may cause severe liver and/or kidney damage, leading to death. Immunizations against these infections are included in the DHLPP vaccine.

Canine Coronavirus-This causes an infectious intestinal disease in dogs of all ages. Symptoms include vomiting and diarrhea, causing the dog to become dehydrated. Vaccines against this virus can also be given with the combination vaccine for distemper, etc. This vaccine is abbreviated DHLPPC. The Corona vaccine can also be given alone and is recommended to begin at 6 weeks of age, follwed by boosters at 9 and 12 weeks and continued annually.

Bordetella Brochiseptica-"Kennel Cough"-This is a bacteria that causes respiratory problems in dogs. It is easily transmitted, so it is important to isolate a dog with kennel cough from other dogs. Any dogs that are boarded are required to have a bordetella vaccine, which is squirted into the nose.

Lyme Disease-This is a bacterial disease also, caused by Borrelia burgdorferi. It is often spread by ticks, but can also be spread by flies and fleas. It causes great stiffness in the joints. Therefore, it is characterized by lameness, along with heart or kidney disease and nerve disorders. A vaccine is available to prevent this disease.

Rabies-This is a viral disease that is fatal when contracted. It attacks the nervous system, causing paralysis and death. Rabies can be transmitted through saliva. Therefore, an infected animal biting another animal can spread the disease. Dogs with rabies are often aggressive and "foaming" at the mouth. A vaccine is available and is required in some states. Animals should get their first rabies vaccine around 3 months of age, with annual boosters. Some vaccines are good for 3 years instead of just 1.

Heartworm Disease-Heratworms live in the heart and lungs, where they can cause permanent damage, and possibly death. They are transmitted by mosquitoes, so all pets are at risk. Heartworm is the common name for Dirofilaria immitis. Dogs can be tested annually for heartworm if they are not on preventative already. A blood sample is taken and used to run quick, simple tests. A preventative is available as a monthly chewable tablet.