Risk Assessment & Biosecurity

what are hazards? give some examples

• any agent that has the potential to cause adverse health effects in animals or humans

• e.g. pathogens (viruses, bacteria, parasites), toxins or poor envi conditions

what are risks

• the likelihood of the occurrence of an event

• and the likely magnitude of the consequences on the system of concern following exposure to a hazard

(risk = likelihood of occurence + consequence) 

For this example, identify the hazard & the risk: 

• A pig farm is located near a forested area with a high population of wild boars

• This farm has inadequate biosecurity measures, such as: no fencing to prevent wild boar access

• hazard: African Swine Fever virus (ASF) carried by infeced wild boars

• risk:

  • likelihood: risk is very high. b/c wild boars have easy access to the farm & have the potential for contamination

  • consequence: potentially outbreak, high pig mortality, mandatory culling

what is risk assessment

= the systematic process of assessing or evaluating the magnitude of the risk of an unwanted outocme resulting from a hazard

what are the 4 main components of the risk analysis process (& how are they interconnected?)

• hazard identifcation

• risk assessment

• risk management

• risk communication

why is risk assessment in animal health important? (4 benefits)

1. prevent disease outbreaks: harzard identification & evaluating risks. providing early warnings to mitigate risks

2. optimizing resource allocation: prioritizing risks based on severity

3. guide decision-making: evidence-based insights for designing prevention & control strategies

4. protects public health: risk of zoonotic disease spreading to human

what are the 6 steps of risk assessement

1. hazard identificaiton

2. entry assessment

3. exposure assessment

4. consequence assessment

5. risk management

6. risk communication

Using the African Swine Fever example, explain how the 6 steps of risk assessment can be applied

1. identifying ASF virus as a hazard in imported pigs

2. assessing thr risk of introducing ASF virus via imported animals, feed or equipment

3. determining how susceptible animals may come in to contact with the hazard (e.g feeding pigs with contaminated swill or direct contact with sick pigs)

4. evaluating potential impact of ASF on animal health, farm producitvity & trade. 

5. desgining measures to control the identified risks (e.g. quarantine protocols, vaccination programs, enhanced biosecurity)

6. sharing risk asssement findings & recommendations with stakeholders

what are the 2 types of risk assessment methods? which type is more commonly used?

• qualitative

  • more commonly used, b/c use less time. so good when immediate action is needed

• quantitative

  • describing risks in numerical values

define what is biosecurity

set of measures designed to

• reduce risk of pathogen

• limit their spread within the farm 

what are the 3 levels at which biosecurity can be applied?

• farm

• regional

• national

what is at the base of all disease control program

biosecurity 

why is biosecurity important? (how does it affect…)

• disease on farms

• production efficiency

• foreign disease

• market competitiveness

• public health

• antimicrobial use

• bases of ANY disease control problem (without biosecurity, none of the disease control measures will hold)

• reduce disease or infection pressure on farm

• improve production efficiency (e.g. faster growth)

• prevent introduction of exotic/foreign diseases (e.g. emerging & re-emerging diseases)

• ensure market access & competitiveness (consumers prefer animal products w/o use of antibiotics)

• protecting public health (zoonotic disease)

• supporting responsible antimicrobial use (AMR & consumer preference)

how to implement biosecurity? (what are the 2 things that we need to understand) 

• how disease/pathogen are transmitted from one agent to another (i.e. how the disease is spread)

• how susceptible animals are exposed

examples of how disease can be spread

• direct contact (animal to animal) 

• aerosol (inhalation of droplets)

• ingestion (oral route)

• vectors (flies, ticks)

• fomites (vehicles, equipment, people)

what are the 2 major components of biosecurity

1. external biosecurity (bio-exclusion)

2. internal biosecurity (bio-containment)

describe how external biosecurity measures work

• prevent intro of pathogen from outside the farm

• e.g. physical barriers or rules banning the introduction of animals, people or vehicles

gives some examples on how to implement external biosecurity measures for the following activity

• purchase of breeding animals & semen

• limiting the frequency of animal introduction

• only purchase from disease free sources (not buying from unknown source)

• implement Good Quarantine Measures

gives some examples on how to implement external biosecurity measures for the following activity

• transport of animals, removal of manure & deadstock

• cleaning the vehicles that were used to transport the animals (e.g. disinfection bath to clean the wheels)

• storage of carcasses to ensure that dead animals are removed & stored in hygienic manner 

gives some examples on how to implement external biosecurity measures for the following activity

• visitors & farmworker movement control

• limiting number of people with access to farm

• wear only farm specific clothes & boots (protects both the human & the animal)

• pig “free” time

  • pig farms often requiring a minimum 24-hour "pig freedom" period away from other pigs before you can visit a new farm

gives some examples on how to implement external biosecurity measures for the following activity

• feed & water supply

• purchasing feed from a trusted source

• regularly (at least once a yr) test the water quality

• regular cleaning of the water pipes

gives some examples on how to implement external biosecurity measures for the following activity

• vermin & bird control

• perimeter fence around the buildings (preventing potential disease vector animals from entering the farm facility)

• place grids/fences over all air inlets to prevent contact btwn wild birds & pigs (for birds)

• implement effective pest control program (include rodents, birds & insects) 

describe how internal biosecurity measures work

• what is the goal?

• aims to limit the spread of pathogens within the farm once they are present (isolation/quarantine to stop the spread of the disease)

• many measures are associated with herd management, cleaning & disinfection

  • internal measures are often associated management methods (e.g. separating the animals by age)

gives some examples on how to implement internal biosecurity measures for the following activity

• disease management

• proper diagnostic, vaccination

• isolation of the sick animals, following procedures in one direction (prevent cross contamination)

• record keeping

• properly store medicines & sterile use of needles

• clear separation of animals of different age groups (start from younger to older)

why start working from young animal then to old animals

the young are naive to most of the disease (have had less exposure)

also their immune system is less well developed compared to the older animals

gives some examples on how to implement internal biosecurity measures for the following activity

• cleaning & disinfection

• develop & implement a production facility cleaning & disinfection program

• frequently clean & disinfect all stables (inc. isolation areas) & equipment used (e.g. cleaning the pig herding board) 

•  select disinfectants based on target organisms & needs

Who should be involved in the biosecurity practices?

everyone is responsible

but some important stakeholders include

• agriculture sector

• NGOs

• academic sector

• gov’t

• public opinion

• industry

• producers of food & agricultural commodities