Preventative EXAM part 1 (copy)

Exam spørsmål, 1-20 (DEL 1)

1.General principles & methods of infectious disease prevention & control

Prevention = measures for preventing and control of infectious diseases in animals. Protects healthy animals, populations, herds, flocks and individuals against potential etiological agents. 3 layers of protection - stopping the disease from entering animal populations and the environment, catching it early and control it if it occur.

Preventative measures can be partial (reduce risk) or complete (fully protect) and include measures to increase specific (vaccine) and non-specific (general health, nutrition) resistance of animals with controlling anthropozoonoses (control of spread bw. animal→human).

1) Types of Prevention

1. Primary measures (before infection) - stopping animals from being exposed at all, ex. quarantine new animals, vaccine

2. Secondary measures (early detection) - Detection disease before CS occur. Ex. regular health checks

3. Tertiary measures (after infection) - treating disease, reduce spread and mortality.

2) National/Veterinary Plans

• each country have yearly disease control plan, based on current disease situation (epizootological) and analysis of territory along with OIE recommendations.

• Programs include disease eradication/elimination plans, vaccination strategies, import/export rules, emergency outbreak plans, methods of diagnosis etc.

3) Protecting Livestock (Farm-level)

• Keeping healthy and sick/dubious animals apart - quarantine

• Separate by species/categories

• Using systems like “all-in-all out”, closed herds, black and white zones, A.I.

• control the environment - safety zones (distance from water sources, roads, humans, wild)

4) Farm management rules (Breeding & Production)

• Protection zones - bw. roads etc.

• Buildings/Equipment - proper ventilation, clean materials, microclimate, sanitation

• Management&Organisation - Regular vet inspections, ID and tracking of animals, Animal separation and selection (avoid genetic diseases), Hygiene and proper nutrition, Transport (reduce stress, correct type, minimise injury, only healthy animals, ventilation, disinfection)

5) Prophylaxis (keep immunity strong)

• Goal: keeping animals resistant to the disease

• Do by ensuring colostrum, vaccination (routine-preventative, emergency), preventive medication (chemoprophylaxis)

6) Preventing disease Entry

• Animal → animal: only introduce healhthy animals - quarantine first, isolate sick ones, examinate.

• Human → human: worker hygiene/education, limit visitors

• Wildlife → animals: control contact/movement, vaccination & vector control

• Sanitation: disinfection, pest control (rodents, insects)

2. General principles & methods of infectious disease elimination & eradication

We have 3 levels of Disease control:

1. control - reduction of disease

2. Elimination - removing it from one area

3. Eradication - removing it from the whole word

1) Disease control

• Control of the disease (incl. elimination & eradication) is done as part of a yearly state vet program (guided by OIE).

• Programs are based on the epizootological situation and analysis of the territory (how common the disease is in the region)

• Reduces number of cases (incidence), total cases (prevalence), morbidity (sickness), and death (mortality) to acceptable levels.

• Must keep applying control measures, to maintain acceptable levels.

2) Elimination

• Goal: reduction of incidence of a disease in a specific geographical area to zero

• But the disease still exists somewhere else, thus it is needed to continue monitoring (surveillance) to prevent reintroduction. Ex. rabies

3) Eradication

• Goal: Zero cases worldwide - permanent reduction of the disease of worldwide incidence caused by a specific agent to zero.

• Continued intervention is no longer needed ex. rinderpest.

How it is done - Strategy:

1. detect and report: identify the disease case early, notify authorities

2. Stop spread, diagnosis & prevent - restrict animal movement, create protection zones, quarantine the animals, testing of animals, vaccination/prophylaxis

3. Find the case source - Foci recognition, determine their limits

4. Decision - method of elimination/eradication of the disease, accoridng to its severity and its ability to spread (incl. manure and carcass disposal, zoonotic ability).

   1. Selective slaughter - only kill selected, save the majority

   2. Depopulation - kill entire herd

   3. Stamping out procedure - kill suspected + all that are in contact with them, also remove and dispose of bedding, manure and carcasses, then clean and disinfect.

3. Disease outbreak determination

An outbreak: series of diseases occuring at higher frequency than usual. (Disease appears in more animals than normal in certain place/time). Quick recognition is essential so that the disease can be controlled early!

Notify: All suspected outbreaks must be reported immediately

• Esp. important for zoonotic diseases

• When a vet is notified of an outbreak, he/she must:

  • Examine affected animals + any carcasses

  • Collect proper lab samples

  • determine number of affected animals

  • Identify the outbreak focus (center) - foci, along with its limits, preventing movement of animals & humans within specific zones. (Setting boundaries, restrictions)

Initial Epizootiological Investigation:

• Goal: origin & spread of infection, determine:

  • animal movement, wind movement at beginning

  • Source of etiological agent, origin of disease, transmission ways

  • propagation inside&outside of outbreak area

  • Previous epizoo situation in the area

  • any environmental risk factors that may incr. chances for spread of disease

  Also: collect samples for lab, identify the sick animals (treatment, isolation or slaughter)

Further investigation - zones are established:

1. Focal zone: Main infected center, highest infection risk

2. Perifocal zone: surrounding infected/susp. area

3. Threatened zone: movement prohibited

4. Tampon (buffer) zone: intensive monitoring

Recognize → report → examine → sample → trace source → restrictions → create zones → monitor.

4. Measures of outbreak of disease & protection zones

1) Intra-Focal Measures (inside the outbreak center)

Actions taken directly at the infected site.

Immediate steps:

• Vet applies emergency precautionary measures on arrival at outbreak site

• Officially report and declare the outbreak to authorities and the public

• Clean, disinfect and sterilize the area, collect samples for lab diagnostics

• Identify and isolate sick animals

• Provide preventive (prophylactic) or treatment measures

• If needed: slaughter infected animals (eradication), destroy vectors (ex. insects), control reservoirs of infection (wildlife/others).

2) Peri-Focal Measures (around the outbreak)

These measures protect surrounding areas from spread.

Actions:

• Sanitation, disinfection, prohibition of animal movement, conduct epizoo investigation

• Public warnings and notifications

• establish checkpoints and perimeter fencing

• install disinfection barriers/fords, vector control, treatment & vaccination, eradication if needed.

3) Threatened zone: animal movement is prohibited, strict surveillance

4) Tampon (buffer) zone: area of intensive observation

• Measures: continuous monitoring, sampling, testing, identify exposed/at-risk animals, emergency vaccination if needed, selective slaughter or full depopulation (stamping out), safe carcass disposal and final disinfection.

• Measures put in place to determine disease source, origin, time of introduction, form/type of disease, transmission routes, spread pattern, previous disease history in the region.

5) Post-focal period (after outbreak control)

• When pathogen is no longer a danger - restrictions can be lifted but monitoring continues, and surveillance remains active.

Detect → report → isolate → disinfect → investigate → restrict movement → vaccinate/eradicate → monitor.

5.Specific Prophylaxis of infectious diseases

Prophylaxis = all general and specific measures used to prevent the outbreak and spread of infectious diseases.

Specific prophylaxis: specific anti-infectious measures given to animals to prevent spread of disease.

• Immunoprophylaxis (passive/active immunity)

• chemoprophylaxis (preventive drugs)

3 Basic periods of immunity:

1. Early postnatal period

• Immune system is immature/incompetent

• Limited Ab (lg) transfer through placenta

• Newborns are agammaglobulinemic (no Ab) - depend on colostrum for passive immunity

2. Adult period

• Fully developed immunity - decrease with age

3. Ageing period

• Immunity declines.

Protection against infections is influenced by internal + external factors during all periods.

Passive immunization: Makes a temporary protection by transferring ready-made Ab from immune/resistant animals to susceptible animals.

• Natural passive immunity: placenta (intrauterine), colostrum, egg yolk. - giving immediate but short-term protection, imp. for young and in early post-natal period.

Active immunization: giving antigen to an animal for it to make a protective immune response.

• Animal actively develops immunity, slower onset, longer lasting

• re-exposure/revaccination → stronger sec. immune response

• Types:

  • Natural active immunization: After recovery from infection

  • Artificial active: Vaccination → Giving Ag to an immunocompetent animal to induce specific active immunity. It is the most effective method of infectious disease control!

6.Passive Immunization in Immunoprophylaxis of infectious diseases

Passive immunization: Temporary protection by transferring ready-made Ab from an immune animal to a susceptible one.

• Duration: usually for 7-21 days.

• Giving immediate protection, but short term.

1) Natural Passive immunization: Protects young in early life (post-natal period). - passage of Ab from mother → embryo.

• Placenta (intrauterine transfer), colostrum (most important, highest Ab absorption in first 24h, protects for 3-4w) and from egg yolk.

2) Artifical Passive immunization: Giving Ab orally or parenterally.

• Ab are made in a donor animal by active immunization and these are then given to susceptible animals for immediate protection.

• sources:

  • Hyperimmune serum: From animals that have been repeatedly injected or given specific Ag, thus contains a very high level of Ab against Ag.

  • Convalescent serum: From recently recovered animals/patients, used against the same disease.

  • Immunoglobulins: Sterile globulin solution from immunized donor plasma.

Types of serum - by species:

• Homologous serum = serum from an animal belonging to the same species

• Heterogenous serum = different species

By Ag specificity:

• Homotypic serum = against same organism

• Heterotypic serum = against different but related organism

By coverage:

• Monovalent serum = one strain/species

• Polyvalent serum = multiple strains/species

Use of Passive Immunization:

1. Maternal: active immunization (vaccine) of mother → Ab passed to newborn (natural passive)

2. Passive artifical:

• Short-term protection: case of high-risk exposure (ex. tetanus anti-serum)

• Simultaneous immunization (serum + vaccine together)

• Serotherapy (treatment of diseases, ex. tetanus, anthrax)

• Immunotherapy (for agammaglobulinemic animals or colostrum-deprived newborns)

7.Active immunization in immunoprophylaxis of infectious diseases

Acitve immunization: Giving Ag to stimulate the animalˋs own immune system to produce a protective immune response.

Animal actively makes its own Ab + immune memory, protection develops more slowly than passive, long-lasting. Macroorganisms actively takes part in the immunity development.

• Reimmunization/Exposure to infection → stronger, faster secondary immune response

Types:

1. Natural active immunization - develops after recovery from infectious disease

2. Artifical active immunization (vaccination)

• Giving vaccine Ag to an immunocompetent animal for them to develop specific active immunity. Most effective method of disease control.

Vaccination = Biopreparations from macroorganisms or metabolic productions of them.

• uses: Preventive (Routine vaccination), emergency, pre-exposure or post-exposure

• Core vaccines: used routinely due to high disease risk

  • feline core vaccines: Panleukopenia, herpes, calicivirus, rabies, FeLv

  • Canine: Distemper, hepatitis, parvo, rabies

• Non-core: Used only if exposure risk is expected. Ex. kennel cough

Types of Vaccines:

1. Live vaccines: Contain living organisms that replicate in the host. Fully virulent - small dose of pathogenic organism, was used against poxvirus, FMD (back in the day). Was long-lasting immunity, passive immunity, for preventive + emergency. Con: Environment is continuouosly infected, vaccine is limited by age, zoonotic risk, may activate latent infections.

2. Attenuated (Avirulent) Live vaccines: Weakened pathogens that do not cause disease, but still induce immunity. Methods of Attenuation: Natural (naturally less virulent strains) & Artifical → Passaging (lapinisation, ovinisation etc.), Passaging in chicken embryos (rabies, sheep pox) and cell culture attenuation (homologous tissue, heterologous - ex. canine distemper - passaging on dog kindley cells).

3. Inactivated (Killed) Vaccines: Microrganisms killed by chemical or physical methods - poorer immunity. Safer than live vaccines, but gives poorer immunity. usually needs adjuvants (lipid). Often need boosters. ex. BRD complex (IBR, BVDV, RSV, Mannheimia), feline panleukopenia, distemper, leptospirosis.

4. Recombinant vaccines: made by genetic engineering.

   1. Subunit vaccine: surface protein gene is inserted into organisms - E.coli. ex. aujeszkyˋs

   2. Gene deletion vaccines: pathogen present but virulence genes removed. Allows differentiation of infected vs. vaccinated. ex. FeLv

   3. Virus vectored: Protective pathogen proteins inserted into vector virus. ex. distemper.

5. Third gen. (DNA vaccines): made of plasmid DNA that has been engineered to make pathogen antigens. Modern vaccine production methods: Ag separation + adjuvant, synthetic Ag production, DNA/Plasmid technology, virulence gene deletion.

8.Types of vaccines, ways of application

Vaccines = Artifical preparations of Ag given to induce immunity without causing disease. Stimulates normal primary immune response.

Preventive, emergency, pre-exposure, post-exposure, core vaccines/non-core.

Types of Vaccines:

• Killed/Inactivated vaccines: contain dead pathogen that cannot replicate. They are activated by physical methods (heat, radiation) or chemical methods (formalin). Given with lipid adjuvants, giving weaker immunity than live vaccines, may need booster doses. ex. Parvo, leptospirosis.

• Recombinant vaccines: uses the virus proteins (proteins made in lab).

  • Subunit vaccines: surface protein gene isolated, protein is grown on E.coli. ex. Aujezky

  • gene deletion vaccines: pathogen present, but pathogenic genes are removed. We can see the difference bw. vaccinated and infected animals. ex. FeLv.

  • Virus-vectored vaccines: the pathogens protective Ag inserted vector virus. Ex. distemper.

• Live vaccines: has living organisms, that can replicate in host.

  • Live attenuated: uses weakened naturally/artificially form of the agent, mimic natural infection → produce strong, long-lasting immunity. But not safe in immunosuppressed, cold storage needed.

  • Modified Live: Live pathogen altered so it cannot cause clinical disease. Mixed with dilutant before use.

• Fully virulent vaccines: Small amount of virulent pathogen, used against pox, FMD. Generally not recommended, as they can actually cause infection.

• 3rd gen vaccines: Use plasmid DNA engineered to make pathogen proteins.

Routes of administration:

1. Parenteral (injection) - SC, IM

2. Intranasal - for IBR, kennel cough

3. Orally by feed or water - used in mass poultry vaccination or wildlife bait vaccination. ex. rabies.

4. Chickens: SC, IM, IV, in Ovo, Aerosol/spray, oculonasal, beak dipping, skin scarification + double sting method.

5. Wildlife: in feed, ex. rabies

9.Factors influencing effectivity of vaccination

A good vaccine should be:

• Stimulating strong immune response

• Give long-lasting immunity

• Be safe and affordable

Vaccine factors:

• all vaccines differ in their potency, whether they are live, attenuated, killed etc. This means that they will also differ in their efficiency & duration of immunity.

• Attenuated vaccines: Immunity last longer but have higher risk for pregnant/immunosuppressed. Also danger of shedding the virus.

• Avirulent: Safer but shorter-lasting.

• Expiry date - expired = reduced/no effect

• Mono/Polyvalent: Must match correct disease strain

• Boosters (annual) & Adjuvants (added to increase immune response).

Host factors:

• Maternal Ab: can inhibit the vaccineˋs effectiveness

• Current illness: vaccine can negatively affect animal if given to already sick animal

• Immune system function: lower response in immunosuppressed, old age.

• Breed - some are more susceptible and may need adjusted schedules for vaccination. ex. rottweiller, Doberman, pitbull - for parvo.

Human factors:

• Incorrect storage of vaccine

• wrong administration route

• wrong timing - immunity needs time to develop, vaccinating too close to exposure may fail

Environmental factors:

• Stress → reduced immune response

• high infection pressure → heavy disease exposure, muntiple animals in one household with many circulating vaccines.

10.Basic principles of vaccinations

Vaccination = prevention and control of infect. diseases through specific immunoprophylaxis.

If around 50% or more of the population is vaccinated, disease spread decr. significantly (herd immunity effect). Diff. species, need specific vaccination programs.

Vaccine principles:

• correct vaccine selection - must match correct pathogen/strain, should protect the animal without harming the animal, humans or the environment.

• check expiry date

• ensure adjuvants are used with killed vaccines

• boosters - given at proper intervals

• Record - document date of vaccination, next date, type, batch number

Host principles:

• only vaccinate healthy animals

• Maternal Ab: can block vaccine response in young, vaccinate when they decline

• age - reduced immune response, as well as sick and pregnant animals

• Breed difference - rottweiller, doberman, pitbull - higher risk, schedule for parvo

Vet principles:

• ensure vaccine is stored correctly

• corect administration

• consider incubation period, if recently exposed → can be too late for vaccine

Environmental principles:

• avoid routine vaccination when animal come from an area with high level of circulating pathogens

Requirements for ideal vaccine:

• high antigenicity - Ag strongly stimulates immunity

• Long-lasting, safe - free of adverse side effects, cheap + stable, suitble for mass vaccination, distinguishable from nautral infection.

Live vaccines should:

• Agent must have good immunogenicity

• Strain should not cause disease/infection in non-vaccinated animals, should be able to replicate in usual tissues of the natural occurring disease.

• Should be easily differentiated from virulent strain, should not make residues in the organism.

Deciding on vaccines: Vaccination of puppies never finishes before 12w of age, polyvalent or monovalent? MLV or inactivated, min. duration of immunity (DOI).

11.Post-vaccination complications

Any unwated local/systemic reactions after vaccination.

Type 1 Hypersensitivity (lgE)

• Cause inflammatory reaction

• can occur after a variety of vaccines = anaphylaxis (immediate allergy). Signs like shock, itching, vomit, diarrhea

Type 2 Hypersensitivity (lgG/lgM) - cytotoxic

• Cause Ab to attach body cells, phagocytosis

• ex. autoimmune hemolytic condition - which is why we must wait for 2w after a vaccination before the animal can undergo surgery

Type 3 Hypersensitivity (Ag-Ab immune complex)

• Cause Ag-Ab complexes deposit in organs, affects the organs not cells.

• results in serum-sickness syndrome → inflammation, rash, fever

Local reactions: usually mild/self-limiting, with pain, erythema, edema.

Other complications:

• Granuloma/Alopecia: nodules or hair loss at injection site - this animal may be at risk for a hypersensitivity reaction ex. anaphylaxis when having booster.

• Injection site sarcoma (cats)

• Contamination: Dirty needle, contaminated vaccine → sec. infection

• Neurological complications: More common with MLV ex. distemper or rabies.

• vaccine-induced disease

• systemic illness - ex. with chlamydia vaccination.

• Shedding: MLV

• complications are more likely in pregnant, aged, sick animals.

• Vaccination errors:

  • Vaccinating too early - maternal Ab still present

  • wrong strain used

  • wrong administration route, poor technique

12.Principles of therapy in infectious diseases; methods

Goal of therapy: restore animal health, recover its productivity, eliminate the animal as a potential source of infection.

Diseases where therapy is NOT recommended: rabies, FMD, TBC, brucellosis, rinderpest, bluetongue, glanders, CSF, ASF, newcastle, toxoplasmosis etc.

General rules:

• Therapy should be forbidden for diseases on the WOAH A-list. ex. Anthrax, FMD, rabies.. (high risk for infection/Zoonosis)

• not recommended in:

  • zoonotic salmonellosis (anthropogenic strains)

  • Mycobacteriosis

  • All prion diseases (no exceptions)

The vet evaulates criteria to decide on the therapy - ethics, economics, epizootological situation & epidemiological aspect.

Methods of therapy:

• Symptomatic and supportive (Non-specific) - focuses on maintaining the animal`s condition

  • Fluid therapy, nutritional, antipyretics (fever reduction), proper housing, calmness

• Casual (specific) - targets the causative agent

  • Vaccines, serum therapy, probiotics, ATBs, antiviral drugs

Essential conditions for successful therapy:

• Early and accurate diagnosis

• Understanding the disease stage and progression

• Isolation of sick and suspected animals

• continuous monitoring

• Strict hygiene measures - disinfection, sanitation, disinfestation

13.Symptomatic, supportive and causal Therapy

1. Symptomatic Therapy

• Targets clinical signs (symptoms) rather than the cause of disease (agent)

• Main goal: making the animal more comfortable & Support the body’s ability to respond to illness

• In some cases, this form of treatment may mask the real symptoms of the disease, ex. pain meds in horses suffering from colic.

Examples of use: parvovirus & diseases where no effective causal therapy exists ex. distemper.

Common treatments: Analgesics (pain relief), Antiemetics (reduce vomiting) & NSAIDs

2. Supportive Therapy

• Does not eliminate the cause, but helps maintain vital body functions

• Supports physiological, biochemical, and metabolic balance

• Main goal: Bringing values back within physiological ranges, by replacing depleted levels of elements - revives the bodies optimal functioning ocnditions (Homeostasis) - To help animal fight the infection more effectively.

Examples: Fluid therapy (rehydration), Vitamins, minerals, Glucose, Antibiotics (to prevent/treat secondary infections), Prebiotics and probiotics.

3. Causal (Specific) Therapy

• Directly targets the etiological agent (cause of disease)

• Must be chosen based on the type + activity of pathogen: Bacteria, Viruses, Fungi or Parasites

Examples:

• Antiviral drugs: Aciclovir

• Antibiotics: for bacterial infections

• Antifungals: Ketoconazole

• Antiparasitics: Ivermectin

Example of treatment for parvovirus:

• Symptomatic - anti-emetic such as metoclopramide, NSAID`s to reduce fever and pain.

• Supportive - fluids IV w/vitamins B1 and K+, glucose, colloid transfusion - hetastarch, recombinant granulocytic colony stimulating factor (neupogen)

• causal - mainly broad-spectrum ATB for 2nd bacterial infection, no real causal treatment except prophylaxis via vaccination.

14.General principles of infectious diseases, Diagnostic

(Diagnostic measures of infectious diseases - general principles)

Aim of Diagnostic measures:

• Identify the etiological agent

• Detect the spread of disease

• Determine the number of infected animals

• Identify the source and cause of the outbreak

Diagnosis According to Mode of Execution:

1. Preventive Diagnosis - Performed routinely by veterinarians

• Includes: Regular health checks & Screening methods

• Goal: early detection, prevention

2. Targeted Diagnosis - when infection is suspected, in foci (disease outbreaks), protected zones/surveillance.

Diagnosis According to Aim:

1. Passive Diagnosis - accidental findings during routine examinations

2. Active Diagnosis - focus on the detection/monitoring of epizootological situation for one or more agents.

• ex. TB testing, representative sample ex. enzootic bovine leukosis

Diagnosis of infectious diseases must be: systemic, complex & specific

According to the epizootological situation, a diagnostic plan should define:

• Number and frequency of examinations

• species and animal categories involved

• selection of diagnostic methods based on disease situation

Diagnostic Methods

1. Field Methods:

Performed directly on-site:

• Case history (anamnesis)

• Collection of epizootiological data

• Clinical examination

• Allergen diagnostics (e.g. tuberculin test for tuberculosis)

• Sampling (following proper “rule of three” packaging)

2. Laboratory Methods:

• necropsy or pathohistology

• Viral methods:

  • virus isolation - cell culture, chicken embryos, lab experiment

  • direct evidence of viral Ag- microscope (IF), Electron microscopy, ELISA, PCR, hybridization

  • Indirect detection of viral Ag - serological testing for specific Ab in serum after inoculation of sample by Ag

  • Indirect evidence of Ag-Ab interaction - Complement fixation test (CFT), haemagglutination test

  • Evidence of viral blocking of Ab - Virus neutralization test (VNT), Hemagglutination inhibition test (HIT)

  • Evidence of direct Ag-Ab interaction - ELISA, IF

• Bacteriological methods:

  • Direct microscopy (ex. mycobacteria)

  • Culture/cultivation

  • biological experiments

• Serological methods: detecting specific Ab reacting with viral Ag

  • Slide agglutination test

  • milk ring test (ex. for brucellosis)

  • Complement fixation test, Virus neutralization, agal gel immunodiffusion, HIT, ELISA

15.Reporting of infectious diseases

Reporting of a notifiable disease is mandatory - can be by the farmer, animal owner or workers. If an owner fails to report a possible disease outbreak, he/she can be legally charged with violation of the law. Animal workers must know how to recognize notifiable diseases.

The report:

• must be submitted immediately, even if the disease is only suspected, and not yet confirmed.

• Sent to vet authorities (regional or state)

Authority on animal diseases:

• The World Organisation for Animal Health (WOAH, formerly OIE), which provides info on:

  • Disease transmission, CS, diagnostics & treatment

  • also set standards on testing needed for international trade

  • specific focus on: Zoonotic diseases + diseases which are on the A-List (WOAH)

Diagnostic Confirmation Process

• Samples are collected and sent for laboratory analysis

• Results are reported to authorities

• Depending on the results, animal owner must give full access by the authorities to the farm. Ex. of such diseases - FMD, BSE, scrapie

Importance of Rapid Reporting

• Limits the spread of disease

• Enables rapid implementation of control measures:

  • Establishment of outbreak zones (foci)

  • Movement restrictions

  • Disinfection barriers

• Allows activation of emergency response plans (if needed)

Measures after suspicion:

• Farmer/owner must now ensure that restrictions are put in place

  • Movement restrictions, isolate suspected animals, limit human access to farm and allow vet inspection and testing

Disease Report Content - Usually prepared by a veterinarian and includes:

• Date of report

• Location/area affected

• Number of suspected cases

• Farms involved

• Control measures put in place

• Possible source of infection (etiological agent introduction)

Reporting Chain

The report is submitted to:

• Regional authorities

• State veterinary authorities

• National agricultural/veterinary institutions

• European Commission (if relevant, within the EU)

16.Emergency planning

Emergency planning consists of prepared response frameworks at national and regional levels that guide actions during disease outbreaks.

Main goals: containment of disease, protection of animal health and productivity, prevent economic losses, protection of public health (esp. in zoonoses).

Most emergency plans use radical methods like slaughter of infected, along with proper disposal. But also quarantine, strict movement control etc.

• Plans may change on basis of epizootological situations, following analysis in a given area or region. (Must be regularly updated).

Key Components of an Emergency Plan in Slovakia for diseases - ex. FMD, BSE, Scrapie, CSF, bluetongue:

1. Legal framework: clearly defined legal authority to enforce control measures (the plan)

2. Financial support: funding given through state budget

3. Organizational structure: Defined hierarchy of vet and governmental authorities. Effective communication and co-operation.

4. Expert support: groups of experts must be available for consultation

5. Resources: access to labs, equipment etc.

6. Staff guidelines and training must be provided

17.Epizootological sanitation

Epizootological sanitation is done to protect the general health of animal population through reducing/eliminating the occurence of etiological agents, vectors and reservoirs.

Used as a preventative measure, and as an eradication and control method. Includes disinfection, disinfestations, carcass disposal etc.

Principles of Epizootological Sanitation

• Can be:

  • General (broad protection)

  • Specific (targeted at a particular pathogen/eitological agent)

• As a preventative method, sanitation should be done regularly and systematically in all facilities. Includes:

  • All-in-all out systems

  • insect and rodent control

  • Intra-focal sanitation - to destroy all sources of infection, vectors and reservoirs. Applied within an outbreak site.

• A change in the epizoo situation and its analysis can indicate the need to increase preventative measures and such - time changes, places etc.

1) Disinfection

• Killing of infectious agents

• Methods:

  • Mechanical: cleaning, scrubbing, hot water + soap

  • Physical: Dry heat, humidity, burning, UV

  • Chemical: After mechanical + physical, we use sprays/liquids depending on etiological agent or surface type. ex. phenols, chloride compounds, pH-based agents, septonex, peracetic acid

2) Disinfestation

• Measures used against vectors and reservoirs (arthropods, rodents) - can be physcial or chemical to remove them.

• Physical: traps, barriers

• chemical: fumigation (gas), insecticides (organochloramines, organophosphates, carbamates, pyrethrins), Rodenticides, molluscicides.

3) Control of Wild Animal Reservoirs

• Mechanical: hunting, trapping

• Physical: flooding burrows/dens

• Chemical: toxic substances (solids or gases)

• Biological: Natural predators & Habitat destruction

Carcass Disposal

Proper disposal is essential to prevent disease spread:

• Rendering (preferred method): Safe, rapid, economical

• Burying or burning: Largely outdated or restricted

• After removal: Thorough cleaning and disinfection of the area

18.Organization and co-ordination of control and eradication of infectious diseases

Organisation and co-ordination are an essential part of any eradication program (regional or national level). It is also very important in emergency plans.

Process of Outbreak Management

1. Detection and Reporting - Disease recognized by owner → report to vet

2. Veterinary Confirmation - Vet evaluates the case → report to institution + state vet department

3. Immediate Control Measures - Owner must put measures into place, such as movement restrictions, sanitation etc.

4. Official investigation - Authorities must be granted full access to the farm, investigation includes clinical, pathological examination & lab testing.

5. Sampling and Control killing - official vet may also decide to do control slaughter for diagnostics - further sample analysis. Samples collected are typ. 2 per animal (with/without anticoagulant ex. EDTA), up to 10 samples per farm.

6. Confirmation and declaration - if lab diagnosis is confirmed → official outbreak is declared, further investigation of surrounding areas begin, considering animal movements, environmental factors (ex. wind sprad) etc.

7. Report - regional authorities (food and vet institute) report to the national level (state vet office). The chief vet officer informs the European Commision (within 24h).

• The chief vet must also report on a weekly basis on occurrence of any secondary outbreaks and these notificaions are recorded on european animal notification system.

Diseases that are notifiable - risk of outbreak: FMD, BSE, Newcastle disease, Scrapie, CSF, ASF, hemorrhagic septicemia, Contagious bovine pleuropneumonia, peste des petits ru, sheep pox, african horse sickness etc.

(WOAH/OIE - list A diseases)

Effective Eradication - what to do:

• Legal powers, financial support, trained personnel, proper equipment, access to diagnostic labs are required for effective eradication.

• Affective areas are mapped and updated regularly - focus (infected zone), peri-focus (protection zone), buffer zone, surveillance zone.

• Sanitation measures - disinfection, disinfestation, rodent control and carcass disposal

• Centre of disease control (organization structure) - imp. to have response teams, such as co-ordination team, administration, epizootiological, vaccination + eradication teams.

• Eradication team is responsible for - planning and carrying out the culling of affected animals, sample collection, carcass disposal, disinfection of equipment and facilities, and to assess animal value (for farmer compensation)

19. International Cooperation in prevention and elimination of infectious diseases

OIE - World Organisation for Animal Health

• Helps to fight animal diseases on a global level through international agreements

• Main role: Collect & share info about animal diseases - most importantly the collection and publication of facts and documents.

  • Control measures & Info on spread of diseases

  • In addition to notifying the goverment or vet authorities

• Both the organisation and the member countries must share all relevant info about animal diseases.

• Member countries must: report listed (by OIE), new diseases and significant epidemiological events within 24h.

• System: WAHIS (World Animal Health information system) = Online reporting system, where info is shared, allowing members to be on-line electronically with a server in the OIE.

WHO (World Health Organisation)

• Focus on Human Health globally - directs + coordinates health within the United Nations system.

• Deals with diseases + their spread, aims to prevent and control diseases across borders.

• Responsible for: Leadership on global health matters, shaping health research agenda, setting standards and guidelines, articulating evidence-based policy options, giving technical support to countries, monitoring and assessing health trends.

CDC - Center for Disease Control and Prevention

• Focus: Public health protection

• Aim is to create the expertise, info and tools that people and communities need to protect their health.

• Main roles:

  • Research information on diseases/conditions globally

  • Detects and investigate health problems

20.Prevention and Eradication of infectious diseases in the EU

There are many agencies working within the EU for the prevention of diseases.

European Commission (Of health and consumers)

• Consist of a general directory with several agencies working underneath, ex. general affairs, consumers, public health, food chain safety, health system, vet office and vet international affairs. “Main EU authority”

Animal Health Office

• Focus: Protect and improve animal health within a community - esp. food producing animals

• They are responsible for:

  • Trade of live animals within EU (intracommunity)

  • Regulation of semen, ova, embryos

  • Products of animal origin & traceability

  • Disease monitoring, control and eradication

  • animal nutrition and veterinary medicines/products

  • Research, funding and emergency response teams

  • Animal welfare

Food and Veterinary Office

• Checks if countries follow EU laws on (checking on EU regulation & Legislation compliance):

  • Animal health & welfare

  • Food and feed safety

• Also helps develop control and inspection systems.

SCFCAH (Standing Community of Food chain and Animal Health)

• Covers the entire food chain (“farm to fork”)

• Helps EU manage health risks related to food and animals

ADNS (Animal Disease Notification System)

• System for reporting important animal diseases

• Ensures: fast communication bw. countries & safe trade of animals

EFSA (European Food Safety Authority)

• Provides independent scientific advice for EU

• performs risk assessments on: food and animal feed along with new/emerging risks

ECDC (European Centre for Disease Control)

• Focus: ensuring strengthened defence against infectious diseases

• Works with national health protection bodies across EU

• collects and evaluate disease data