4 H Viral Diseases

8/4/2019 4 H Viral Diseases

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Viral Diseases

4-H Veterinary Science

Extension Veterinary Medicine

Texas AgriLife Extension Service

College of Veterinary Medicine and Biomedical SciencesTexas A&M System

http://aevm.tamu.edu


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Objectives

Describe pox diseases

List and describe common viral respiratory

diseases

Describe viral abortion diseases

Describe meningitis and encephalitis

Describe hepatitis

Describe anemia


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Background

Remember

Five infectious diseases

Bacterial

Viral

Fungal

Parasitic

Rickettsial


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Infectious disease

An illness due to a specific infectious agent or its

toxic products that arises through transmission of

that agent or its products from an infected person,animal or reservoir to a susceptible host, either

directly or indirectly


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Viruses

Viruses

An ultra-microscopic micro-organism, parasitic

within living cells and of which many can

cause disease. They consist of a strand ofnucleic acid (DNA orRNA) that contains

genetic instructions concerning viral

reproduction that is enveloped by a protein

coat Not alive nor dead, has DNA orRNA, makes

copies of itself, must be inside a living cell


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Antibiotics have no affect

Treatment is to easy symptoms

Vaccines available

Entrance of virus into cell is viral infection

Virus uses cell structures to replicate new viruses


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Animal viruses look like

Capsid Outer shell

Core Surrounds genetic material

Envelope Kind of life skin around outside of virus

Lipid bilayer (membrane)

Genetic material

Function

Make more viruses


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Harmful

Replication leads to cell death

Takes over cell function

How exit cell

Budding

Few at a time

Lysis

Cell membrane ruptures


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All living things can be affected Animals

People

Plants

Infectivity Single species

Humans smallpox

1-2 Species Influenza

Particular kind of plant Tobacco mosaic virus

Particular species of bacteria Lambda bacteriophage E.coli


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Different kinds of viruses

Double-stranded DNA

Single-stranded DNA

Double-strandedR

NA Single-strandedRNA

Retroviruses

Unique kind of single-stranded RNA virus

Can mutate

Kill virus

Make new-strain


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Infectivity

The characteristic of a disease agent that

embodies capability of entering, surviving in,

and multiplying in a susceptible host

Basically

How efficiently it invades specific animals tissues


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Specificity

Its ability to infect certain animal species and

tissues


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Symptoms Depend on tissue affected

Skin

Blood

Liver Uterus

Fetus

Brain

Lungs

Stomach Intestines

Bloodstream (viremia) Phase of the disease


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Exposure symptoms

Recent exposure

Normal incubation period

Long ago exposure

Replicate/multiply immediately

May become dormant

Recrudesces

After stressful event

After incubation period may exhibit symptoms


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General Conditions

Hepatitis

Infectious canine hepatitis (ICH) Causes

Liver inflammation

Viremia

Affects liver, kidneys, spleen and lungs Not zoonotic

Symptoms Decreased appetite

Appear depressed

Fever

Opacity of one or both corneas of their eyes (so-called Blue Eye)

one to two weeks later Respiratory signs

Eye and nose discharge

Cough

Prevention Vaccine (puppy)


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Anemia

Systemic viral disease

Transmitted Vectors

Vehicles

Symptoms Fever

Anemia

Weight loss

Abortion

Examples Equine Infectious Anemia (EIA)

Bluetongue cattle

Leukosis cattle

Malignant catarrhal fever - cattle


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Skin

Warts Definition

Fibrous tumors of the skin and occasionally the

mucous membranes

Species affected Animals

Cattle, dogs, rabbits

Humans

Transmission Direct contact

Arthropods

Symptoms

Cauliflower-type growths Head Neck

Shoulder

Mouth

Vulva

Penis

Vaccine available


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Pox Definition

Acute skin condition caused by replication ofpoxviruses in the skin

Transmission Direct transmission (through skin)

Arthropods (vectors)

Types of lesions Bumps

Blisters

Pustules

Crusts

Named after affected animals


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Fowl Pox

Fowl Pox

Swine Pox

Cow Pox


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Respiratory System

Pneumonitis; Pneumonia

Contagious infection of the lungs and causes severedamage to the lung

Causes

Hemorrhages

Edema

Emphysema

Bacteria can complicate

Symptoms

Cough

Fever

Heavy breathing

Lethargy

Decreased appetite


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Viral respiratory diseases Infectious Bovine Rhinotracheitis (IBR)

Bovine Parainfluenza-3 (PI)

Equine Rhinopneumonitis

Equine Influenza Swine Influenza

Canine Infectious Tracheobronchitis (Kennel Cough)

Canine Distemper

Feline Viral Rhinotracheitis (FVR)

Feline Calicivirus (FCV) Fowl Infectious Bronchitis

Fowl Infectious Laryngotracheitis (LT)

Fowl Influenza


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Reproductive System

Abortion

Viruses terminate pregnancy by attacking

Fetus

Embryo

Placenta

Uterus

Examples

Swine parvovirus

I

nfectious bovine rhinotracheitis (I

BR

) Bovine viral diarrhea (BVD)

Swine pseudorabies

Equine rhinopneumonitis


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Nervous System

Meningitis

Definition

Inflammation of the brain covering (meninges)

Encephalitis

Definition

Inflammation of the brain tissue

Causes damage to brain tissues


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Digestive System

Gastroenteritis

Affects

Stomach

Intestines

Highly contagious

Symptoms

Vomiting

Diarrhea More severe in young

Dehydration and electrolyte imbalance


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Types

Rotavirus

Coronavirus

Parvovirus Feline panleukopenia

Bovine viral diarrhea (BVD)

Swine transmissible gastroenteritis (TGE)


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Summarize

Viral condition Affects System

Encephalitis Brain Nervous

Hepatitis Liver General

Anemia Blood General

Abortion Fetus Reproductive

Meningitis Meninges Nervous

Gastroenteritis Stomach,

intestine

Gastrointestinal

Pneumonitis Lungs Respiratory

Warts Skin Skin


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Meningoencephalitis

Symptoms

Depression

Blindness

Partial or complete paralysis

Wobbling

Seizures

Coma

Delirium


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Vaccination is important

No treatment

Types

Rabies

Equine encephalomyelitis

VEE, WEE, EEE

Canine distemper

Parvovirus

Swine pseudorabies

Documents

4 H Viral Diseases