ANS 2/6

Contextual setup of the class session focusing on vaccination immunity and zoonotic diseases.
Acknowledgment of the presence of a friend, Carly.

Discussion of potential reasons for vaccine failure, categorized into:
- Human error:
- Use of an expired vaccine.
- Improper storage (temperature-related issues).
- Wrong dosage administration.
- Proper adherence to vaccines is typically high among vet techs and veterinarians, making human error less common.
- Animal factors:
- The subject animal may not respond to vaccination due to inherent immunological reasons.
Illustration: Example shared about a puppy contracting parvovirus despite vaccination.

Explanation of the inability to use antibiotics for viral infections:
- Antibiotics target bacteria, not viruses; instead, supportive care is provided.
Understanding viral infections in hosts:
- Viruses replicate inside host cells and hijack biochemical processes.
- Presence of memory cells from previous vaccinations enhances response to infections.
Antiviral medications:
- More commonly used in human medicine (e.g., for COVID-19) than in veterinary settings.

Discussion around vaccine safety for special populations:
- Options presented:
- A) Attenuated vaccine
- B) Inactivated or killed vaccine
- C) Modified live vaccine
- D) No vaccines are safe for pregnant animals
Discussion of suitable vaccine administration sites:
- Stimulating learning through a question about the appropriate injection location (e.g.,
  armpit region).
Focus on passive immunity:
- Question posed about methods of gaining passive immunity (e.g., maternal antibodies).

Definition: Zoonotic diseases (zoonoses) are illnesses transmitted from animals to humans.
Identification of vulnerable populations prone to zoonotic infections:
- Very young, elderly, immunocompromised individuals, and pregnant individuals.
Transmission methods:
- Bites and scratches from infected animals.
- Environmental contamination (e.g., bedding, water sources).
- Direct contact with animal bodily fluids (saliva, feces, urine).
- Vectors (e.g., mosquitoes) that facilitate transmission.
- Transplantation and transfusion potentially carrying infectious agents.
- Ingestion of contaminated food products.

1. Viral Diseases:
- Must have a living host for replication.
2. Bacterial Diseases:
- Single-celled organisms that can transmit zoonoses.
- Specific disease examples discussed, including:
- Lyme disease, often associated with tick bites.

Rabies:
- Transmission through saliva, open wounds, or bites.
- Symptoms evolve through four characteristic stages:
- Stage 1: Prodromal stage with anxiety, behavioral changes.
- Stage 2: Excitatory stage, aggression, hydrophobia.
- Stage 3: Neurological impairment, paralysis.
- Stage 4: Results in death.
- Treatment focuses on prevention; once symptoms appear, rabies is nearly 100% fatal.

Newcastle disease:
- Affects domestic poultry, aerosol and fecal transmission routes.
- Symptoms in birds include respiratory issues, growth retardation.
Western Equine Encephalomyelitis (WEE):
- Transmitted by mosquitoes; affects horses and humans.
- Symptoms include neurological impairment and gait irregularities.
Chlamydiosis:
- Also known as parrot fever, primarily affects birds; aerosol transmission.
Salmonella:
- Potential to cause gastrointestinal infections in humans, typically through ingestion.
- Prevention methods include treating and controlling contaminated environments.
Cat Scratch Fever (CSD):
- Caused by Bartonella henselae, transmitted through scratches or bites.
- Symptoms in humans include swollen lymph nodes and fever; often self-limiting in healthy individuals.

Ringworm (Dermatomycosis):
- Fungal infection, commonly misunderstood as a worm; very contagious.
- Symptoms: circular patches, redness, itching.
- Treatment involves antifungal medications and significant cleaning to prevent reinfection.

Overview of the importance of prevention and vaccination in managing zoonotic diseases and enhancing animal health; encouragement to apply learned knowledge in practical situations.