Illness

Rabies virus. A fatal viral disease that attacks the brain and nervous system. Zoonotic, meaning it spreads to people.

Top symptoms

• Behavioral change: aggression or unusual friendliness
• Ataxia (loss of coordination), progressing to paralysis
• Hypersalivation
• Seizures

If your dog gets it

There is no treatment once symptoms appear. Rabies is essentially always fatal at that point. Exposed unvaccinated dogs face mandatory quarantine or euthanasia under California public health law. This is why the vaccine is the one legal requirement in the state.

Illness

A highly contagious virus that attacks the respiratory, digestive, and nervous systems at the same time.

Top symptoms

• Fever, nasal and eye discharge, coughing
• Vomiting and diarrhea
• In advanced cases: seizures, muscle twitching, paralysis
• Hardened, thickened footpads in some cases

If your dog gets it

There is no cure. Treatment is supportive only: fluids, antibiotics for secondary infection, and anticonvulsants if neurological signs appear. Dogs that survive are often left with permanent nerve damage. Mortality is high, especially in unvaccinated puppies.

Illness

An extremely contagious virus that attacks the lining of the gut and the bone marrow.

Top symptoms

• Severe vomiting
• Profuse, often bloody diarrhea
• Lethargy and refusal to eat
• Rapid dehydration, fever or low body temperature

If your dog gets it

No direct antiviral exists. Treatment means hospitalization with IV fluids, anti-nausea medication, and antibiotics to prevent the sepsis that can follow gut damage. Survival depends heavily on how fast treatment starts. Untreated, mortality is very high, especially in puppies.

Illness

The vaccine covers two related viruses: CAV-1, which causes infectious canine hepatitis (a liver disease), and CAV-2, a respiratory pathogen and one of the kennel cough contributors.

Top symptoms

• Hepatitis (CAV-1): fever, lethargy, vomiting, abdominal pain, jaundice, cloudy “blue eye”
• Respiratory (CAV-2): cough, nasal discharge, mild fever

If your dog gets it

No antiviral treatment exists, only supportive care. CAV-2 alone tends to be mild and self-limiting. CAV-1 hepatitis can be fatal in severe cases, especially in young dogs, which is why it is grouped as core even though the everyday risk people picture is the milder respiratory form.

Illness

Bordetella bronchiseptica, a bacterium and one of the main causes of kennel cough. Spreads easily through the air and direct contact anywhere dogs gather.

Top symptoms

• Persistent, harsh, honking cough
• Occasional nasal discharge or “reverse sneezing”
• Mild fever in some cases

If your dog gets it

Most healthy adult dogs recover on their own with no treatment at all, or with a short course of antibiotics if it lingers. Puppies, seniors, and dogs with weaker immune systems are at higher risk of it progressing to pneumonia. Most boarding and daycare facilities require this vaccine before entry.

Illness

A bacterial infection carried in contaminated water and soil, spread through wildlife urine. Zoonotic, meaning people can catch it too.

Top symptoms

• Fever, lethargy, loss of appetite
• Vomiting, increased thirst and urination
• Jaundice in more severe cases

If your dog gets it

Treated with a course of antibiotics, most often doxycycline. Left untreated, it can progress to life-threatening kidney or liver failure. Dogs with hiking, camping, or standing-water exposure are at higher risk, which is common in San Diego’s canyon and trail areas.

Illness

Borrelia burgdorferi, a bacterium spread by tick bites. Far more common in the northeast and upper midwest than in Southern California.

Top symptoms

• Lameness that shifts from leg to leg
• Swollen joints and lymph nodes
• Fever, lethargy, reduced appetite

If your dog gets it

Treated with about 4 weeks of antibiotics, usually doxycycline. Most dogs improve within a couple of days of starting treatment. Left untreated, a small percentage of dogs develop a serious kidney condition called Lyme nephritis. Regional risk is the deciding factor for this vaccine, not a blanket recommendation.

Illness

A flu virus (H3N8 or H3N2 strains) that spreads quickly wherever dogs are in close contact. Not contagious to people.

Top symptoms

• Cough, often persistent
• Nasal and eye discharge
• Fever, lethargy, reduced appetite

If your dog gets it

Supportive care: rest, fluids, and antibiotics only if a secondary bacterial infection sets in. Most dogs recover, though it can progress to pneumonia in vulnerable dogs. Frequently required alongside Bordetella at boarding and daycare facilities.