Veterinary Public Health & Epidemiology: Veterinary Public Health- Epidemiology-Zoonosis-One Health

Preface
Contents
About the Authors
Abbreviations
1: Veterinary Public Health
	1.1 Definitions
		1.1.1 Office International des Epizooties (World Organization for Animal Health)
		1.1.2 World Health Organization (WHO): VPH
			1.1.2.1 A Sustainable Relationship
		1.1.3 Veterinary Public Health Functions
		1.1.4 Areas of Activities
		1.1.5 Other VPH Core Domains
		1.1.6 VPH: Newer Areas of Activities
			1.1.6.1 Political Upheaval and Trichinellosis
			1.1.6.2 Natural Disasters and Plagues
			1.1.6.3 Bioterrorism
	1.2 Selected Areas of VPHE (Recommended in 1975 and 1999)
		1.2.1 Epidemiology
		1.2.2 Zoonoses
		1.2.3 Food Hygiene
			1.2.3.1 Healthy Food Animals and Safe Produce
			1.2.3.2 Effects of Climate Change and Global Warming
		1.2.4 Rural Health
	1.3 VPHE Organization and Evolution
		1.3.1 An Example (Based on the Experience of Investigating the Japanese Encephalitis Epidemic in Champaran in 1980)
	References
2: Zoonoses
	2.1 Definition
	2.2 Classification of Zoonoses
		2.2.1 Based on the Maintenance Cycle of the Infectious Agent
		2.2.2 Based on the Direction of the Transmission of the Agent (Fig. 2.5)
		2.2.3 Based on the Nature of the Causative Agent
		2.2.4 Based on Likely History (Hart et al. 1999)
		2.2.5 Other Classification of Zoonoses
		2.2.6 Mechanism of Emergence of Disease
			2.2.6.1 Environmental Changes
			2.2.6.2 Emergence and Re-emergence
		2.2.7 Anthropogenic Factors/Determinants of Zoonoses
		2.2.8 Management of Zoonoses
			2.2.8.1 Conventional Approach (Veterinary Service-Veterinary Public Health)
			2.2.8.2 Multi-sectoral Approach (One Health)
			2.2.8.3 Drivers of Diseases-One Health Team
			2.2.8.4 One Health Is Economical
	References
3: Epidemiology
	3.1 Introduction
	3.2 Objectives and Application of Epidemiology
	3.3 Types of Epidemiology
		3.3.1 Based on the Fundamentals/Basics
		3.3.2 Based on Diagnostic Methods and the Diagnosis of Infection/Disease
		3.3.3 Based on Attributes in the Study Population
		3.3.4 Based on Application
	References
4: Ecological Concept
	4.1 Persistence of a Natural Nidus of Infection
	4.2 Escape of an Agent and the Formation of a New Nidus
	4.3 Landscape Epidemiology
	Reference
5: Causation of Disease
	5.1 Different Hypothesis of Disease Causation
	5.2 The Multiple Causality Hypothesis and Its Utility
	5.3 Drivers of Disease in the Population
	References
6: Agent, Host, and Environmental Factors
	6.1 The Agent
	6.2 Host
	6.3 Environment
	6.4 Husbandry Practices
	6.5 Time
	References
7: Disease Transmission
	7.1 Infection Process
		7.1.1 Latent and Patent Infection
	7.2 Modes of Transmission
	7.3 Mysterious Mechanisms of Transmission
8: Disease Distribution in Population
	8.1 Sporadic
	8.2 Outbreak, Epidemic, and Pandemic
	8.3 Endemic
	8.4 Emerging Diseases
	8.5 Cyclic Epidemic Curve
	8.6 Secular Epidemic
	References
9: Data in Epidemiology
	9.1 Classification of Data
	9.2 Classification of Data Based on Source
	9.3 Methods of Collection of Primary Data
	9.4 Characteristics of Data
	9.5 Bias in Data
	9.6 Coding of Data
	9.7 Important Sources of Veterinary Data
	9.8 Distribution of Data Set
	References
10: Measures of Disease
	10.1 Morbidity Measures
		10.1.1 Specific Morbidity Rates
		10.1.2 Attack Rate
	10.2 Mortality Rates
	10.3 Ratios
	10.4 Formula for Measuring Production
	10.5 Explanation and Exercise
11: Strategies of Epidemiology
	11.1 Descriptive Epidemiology
		11.1.1 Surveys
		11.1.2 Surveillance
		11.1.3 Monitoring
		11.1.4 Reporting
		11.1.5 Formulation of Hypotheses
	11.2 Analytical Epidemiology
	11.3 Experimental Epidemiology
	11.4 Theoretical or Mathematical Epidemiology or Modelling
	11.5 Types of Epidemiological Studies
		11.5.1 Cross-Sectional
		11.5.2 Longitudinal
			11.5.2.1 Cohort Studies
			11.5.2.2 Case-Control Study
	11.6 Exercise: Study the Attributes of a Herd Disease
	Reference
12: Sampling Techniques
	12.1 Classification
	12.2 Probability Sampling
	12.3 Non-probability Sampling
	12.4 Steps in Random Sampling
	12.5 General Rules on Sampling
	12.6 Sample Size for Different Types of Studies
	12.7 Exercise
		12.7.1 Selection of Population for Study and Methods of Sampling
		12.7.2 Surveillance and Monitoring
		12.7.3 Definitions (as per OIE)
		12.7.4 Disease Survey
			12.7.4.1 Explanation of Certain Terms of Interest
			12.7.4.2 Random Sampling Techniques
			12.7.4.3 Sampling Frame
				Two-Stage Sampling
				Random Geographic Coordinate Sampling
				Stratification
				Probability Proportional to Size Sampling (PPS)
	Reference
13: Measurement of Causal Association
	13.1 Risk and Its Measurement
	13.2 Measures of Strength
		13.2.1 Relative Risk
		13.2.2 Odds Ratio (OR)
		13.2.3 Population Relative Risk (RRpop)
		13.2.4 Population Odds Ratio (ORpop)
	13.3 Measures of Effect
		13.3.1 Attributable Risk
		13.3.2 Attributable Fraction (AF)
		13.3.3 Estimated AF
	13.4 Measures of Total Effect
		13.4.1 Population AR (PAR)
		13.4.2 Population Attributable Fraction (PAF)
		13.4.3 Estimated PAF
	13.5 Relationship Between AR and RR
	13.6 Statistical Association
		13.6.1 Chi-Square
		13.6.2 Correlation Analysis
		13.6.3 Regression Analysis
		13.6.4 Multivariate Analysis
	13.7 Synergy in Multifactorial Causation of Diseases
	13.8 Exercise
		13.8.1 Estimation of Risk: Calculation of RR, AR, and OR
		13.8.2 Determination of Additivity/Independence of Factors Causing Disease
		13.8.3 Evaluation of an Intervention Measure
	References
14: Investigation of an Outbreak
	14.1 Descriptive Epidemiology
		14.1.1 Formulation of Hypothesis
		14.1.2 Evaluation of Hypothesis
	14.2 Analytical Epidemiology
	14.3 Experimental Epidemiology
	14.4 Report Writing and Submission
	14.5 Exercise
		14.5.1 Investigation of Food Poisoning Outbreak
			14.5.1.1 Observation, Analysis, and Inferences
		14.5.2 Searching Causal Factor
	Reference
15: Diagnostic Test and Its Evaluation
	15.1 Properties of Diagnostic Test
		15.1.1 Reliability
		15.1.2 Validity
		15.1.3 Accuracy
		15.1.4 Likelihood Ratio
		15.1.5 Multiple Testing
		15.1.6 Concordance
		15.1.7 Selection of Cut-Off Point
		15.1.8 Receiver-Operator Characteristic (ROC) Curve
	15.2 Exercise
		15.2.1 Validity of Screening Test
	References
16: Surveillance
	16.1 Set-up for National Disease Surveillance
	16.2 Why Surveillance Is Required
		16.2.1 Diseases Not Present
		16.2.2 Diseases Present
	16.3 Characteristics of Surveillance
	16.4 Classification
		16.4.1 Based on Who Makes the Primary Observation
		16.4.2 Based on the Frequency of Observations
		16.4.3 Other Approaches
	References
17: Prevention, Control, and Eradication of Disease
	17.1 Prevention
	17.2 Methods of Disease Prevention
		17.2.1 Quarantine
		17.2.2 Mass Vaccination
		17.2.3 Environmental Measures
			17.2.3.1 Portable Calf Pen
			17.2.3.2 McLean County System
		17.2.4 Chemoprophylaxis
		17.2.5 Early Detection
		17.2.6 Mass Education/Awareness
	17.3 Disease Control
		17.3.1 Reservoir Control
		17.3.2 Vector Control
		17.3.3 Test and Slaughter
		17.3.4 Mass Treatment
		17.3.5 Miscellaneous
	17.4 Disease Eradication
		17.4.1 Test and Slaughter
		17.4.2 Vector Eradication
	17.5 Integrating the Concept of Disease Process and Principles of Disease Management
	References
18: Economics of Disease
	18.1 Partial Farm Budget
	18.2 Measures for Selecting a Control Campaign
		18.2.1 Net Present Value (NPV)
		18.2.2 Benefit-Cost Ratio (B/C)
			18.2.2.1 Illustrations (Schwabe 1969)
				Cost of a Single Case of Dog Bite in California in 1981
				Cost of Brucellosis in India (1970)
		18.2.3 Internal Rate of Return (IRR)
		18.2.4 Payback Period
	18.3 Definitions
	References
19: World Organization for Animal Health (WOAH)/Office International Des Epizooties (OIE)
	19.1 Organization Set-up
	19.2 How WOAH Functions
	Reference
20: Food-borne Infections and Intoxications
	20.1 Population, Pathogen, and Food and Its Production, Processing, and Trade
		20.1.1 Food Preference: Raw or Lightly Cooked Dishes (Examples) and the Farming System
	20.2 Source of Pathogens: Food Animal Production (Farming) System; Processing and Trade
	20.3 Causes
		20.3.1 FB Parasitic Disease Burden
		20.3.2 Parasites
		20.3.3 Viruses
		20.3.4 Bacteria
	20.4 Classes of Food and the Respective Common Pathogens
	20.5 Important Fish-Borne Intoxication
		20.5.1 Ciguatera Poisoning
		20.5.2 Palytoxin
		20.5.3 Tetrodotoxin (TTX)
	20.6 Burden of FBDs
	20.7 How to Mitigate
	20.8 Mitigation Approaches and Methods
		20.8.1 FAO Food Chain Crisis-Intelligence and Coordination Unit (FCC-ICU)
		20.8.2 Harmonised Inspection
		20.8.3 FoodNet
		20.8.4 HACCP (Hazard Analysis Critical Control Points)
	References
21: Food-borne Disease Outbreak Investigation
	21.1 Example
		21.1.1 Preliminary Assessment of the Situation
		21.1.2 Epidemiological Analysis
			21.1.2.1 Hypothesis Testing by Retrospective Cohort Study
			21.1.2.2 Hypothesis Testing by Retrospective Case-Control Study
			21.1.2.3 Distribution of Exposure
			21.1.2.4 Comments
		21.1.3 Environmental Investigation
		21.1.4 Source Attribution
			21.1.4.1 Illustrative Example (Source: https://www.cdc.gov/salmonella/newport-07-20/index.html)
		21.1.5 Process of Linking a Case to an Outbreak
			21.1.5.1 Assessing the Level of Exposure/Dose-Responses
	Reference
22: Foodborne Viral Infections
	22.1 Norovirus (NoV)
		22.1.1 The Virus
		22.1.2 Prevalence
		22.1.3 Transmission
		22.1.4 Source
		22.1.5 Symptoms
		22.1.6 Surveillance
	References
23: Hepatitis Viruses
	23.1 Hepatitis A Virus (HAV)
		23.1.1 Virus
		23.1.2 Reservoir
		23.1.3 Source
		23.1.4 Survival of Virus
		23.1.5 Transmission
		23.1.6 Distribution
		23.1.7 Symptoms
		23.1.8 Diagnosis
		23.1.9 Treatment
		23.1.10 Prevention
	References
24: Hepatitis E Virus (HEV)
	24.1 Distribution
	24.2 Virus
	24.3 Reservoir
	24.4 Source
	24.5 Routes of transmission
	24.6 Symptom
	24.7 Diagnosis
	24.8 Treatment
	24.9 Prevention
	References
25: Rotavirus
	25.1 Aetiology
		25.1.1 Classification of Group A Rotavirus (RVA)
	25.2 Epidemiology
	25.3 The Global Burden of Disease
	25.4 Transmission
	25.5 Zoonotic Potential
	25.6 Pathogenesis
	25.7 Symptoms
	25.8 Diagnosis
	25.9 Control and Prevention
	25.10 Vaccination
	25.11 Treatment
	25.12 Prevention
	References
26: Bovine Spongiform Encephalitis (BSE)/Mad Cow Disease
	26.1 CJD and vCJD
	26.2 Routes of Infection
	26.3 BSE and vCJD
		26.3.1 Epidemiology
		26.3.2 Sources of Infection
		26.3.3 Aetiology
			26.3.3.1 Prion: Properties
			26.3.3.2 BSE- Prion Protein
		26.3.4 Pathogenesis
	26.4 Signs and Symptoms of BSE
	26.5 Public Health Significance: vCJD
		26.5.1 Symptoms vCJD
		26.5.2 Timeline
	26.6 Diagnosis
		26.6.1 Specific Tests and Methods
	26.7 Treatment
	26.8 Prevention
	26.9 Prevention and Control of BSE
	References
27: Viruses Occasionally Reported as Foodborne
	27.1 Detection of Virus
	27.2 Sources
	27.3 Stability of Viruses and Processes of Decontamination
	27.4 Effective Control Measure
		27.4.1 Intervention Methods
	References
28: Foodborne Bacterial Infections
	28.1 Salmonellosis
	28.2 Aetiology
	28.3 Epidemiology
	28.4 Pathogenicity
		28.4.1 Typhoidal and Non-typhoidal Salmonella
	28.5 Symptoms
	28.6 Diagnosis
	28.7 Outbreaks
	28.8 Outbreaks of Foodborne Salmonellosis
		28.8.1 Raw Fruits, Vegetables and Sprout as Sources of Human Salmonellosis
		28.8.2 Egg-Associated Outbreak (ECDC-EFSA 2017)
		28.8.3 Outbreak (Brazil Nuts)
		28.8.4 Multi-Country Outbreak of Salmonella Agona
	28.9 Control
	28.10 Poultry, Pet and Domestic Animal Salmonellosis
		28.10.1 Poultry Salmonellosis
			28.10.1.1 Pullorum Disease
			28.10.1.2 Signs and Symptoms
				Fowl Typhoid (Gallinarum)
			28.10.1.3 Signs and Symptoms
			28.10.1.4 Diagnosis
			28.10.1.5 Laboratory Diagnosis
			28.10.1.6 Control
		28.10.2 Dog Salmonellosis
		28.10.3 Swine Salmonellosis
			28.10.3.1 A. Septicaemia
			28.10.3.2 B. Enteritis
			28.10.3.3 C. Salmonella Typhimurium Infection
		28.10.4 Bovine Salmonellosis
			28.10.4.1 A. Septicaemia: Salmonella Dublin Infection
			28.10.4.2 B. Acute Enteritis
			28.10.4.3 C. Subacute Enteritis
			28.10.4.4 D. Chronic enteritis
		28.10.5 Sheep Salmonellosis
		28.10.6 Equine Salmonellosis
	28.11 Control of Salmonellosis in Domestic Animals
	References
29: Escherichia coli
	29.1 Pathogenic E. coli
	29.2 E. coli Associated with Food Poisoning/Gastroenteritis
		29.2.1 Invasive E. coli
		29.2.2 Shiga toxin-producing E. coli (STEC)
	29.3 Symptoms
	29.4 Extra-Intestinal Infections
		29.4.1 Uropathogenic E. coli (UPEC)
		29.4.2 E. coli Neonatal meningitis
	29.5 Diagnosis
		29.5.1 Bacterial Culture
		29.5.2 DNA Fingerprinting (CDC PulseNet = Pulsed-Field Gel Electrophoresis (PFGE) Patterns)
	29.6 Treatment
	29.7 Prevention
	References
30: Klebsiella spp.
	30.1 K. pneumoniae
	30.2 Pathogenic Factors
		30.2.1 Virulent and Hypervirulent Lineages (Dorman et al. 2018)
	30.3 Epidemiology
	30.4 Animals
	30.5 Environment
	30.6 Food
	30.7 Human
	30.8 Disease
	30.9 Diagnosis
	30.10 K. oxytoca
	30.11 Epidemiology and Clinical Importance of K. pneumoniae Carbapenemases (KPC)
	30.12 Prevention
	References
31: Aeromonas hydrophila
	31.1 Virulence Factors
		31.1.1 Enterotoxins
		31.1.2 Specialized Protein Secretion Machinery (TTSS)
	31.2 Public Health Problem
	31.3 Epidemiology
	31.4 Sources
		31.4.1 Pathogenic Species
			31.4.1.1 Gastri-intestinal
			31.4.1.2 Extra-intestinal
				Health of Other Terrestrial and Aquatic Animals
	31.5 Diagnosis
	31.6 Prevention and Control
	References
32: Staphylococcus aureus
	32.1 Staphylococcus aureus
	32.2 Common Characters of S. aureus
	32.3 Virulence Factors
	32.4 Pathogenesis
	32.5 Food Poisoning
	32.6 Source of S. aureus
	32.7 Symptoms
	32.8 Diagnosis
	32.9 Treatment
	32.10 Prevention
	32.11 MRSA or Methicillin-Resistant Staphylococcus aureus
		32.11.1 Symptoms
		32.11.2 Diagnosis
		32.11.3 Prevention
	References
33: Streptococcus suis
	33.1 Aetiology
	33.2 Epidemiology
		33.2.1 Distribution of Serotypes
			33.2.1.1 Infection in Animals
			33.2.1.2 Infection in Human
		33.2.2 Sequence Types and Distribution
	33.3 Virulence Factors
	33.4 Pathogenesis
	33.5 Disease
	33.6 Symptoms
	33.7 Diagnosis
	33.8 Prevention
	References
34: Clostridium perfringens
	34.1 Common Vehicles/Sources
	34.2 Pathogenesis
	34.3 C. perfringens Type C
		34.3.1 Cpe Negative C. perfringens Type A
	34.4 Diagnosis
	34.5 Histotoxic Infections
	References
35: Botulism
	35.1 Aetiology
	35.2 Botulinum  Neurotoxins (BoNTs)
		35.2.1 C. botulinum
			35.2.1.1 Botulinum Toxin Producing Clostridia
			35.2.1.2 Non-Clostridia (Rasetti-Escargueil et al. 2020)
	35.3 Epidemiology
		35.3.1 Source
		35.3.2 Modes of Infection (Forms of Botulism)
		35.3.3 Public Health Reports
	35.4 Symptoms
		35.4.1 Infant Botulism
	35.5 Diagnosis
	35.6 Treatment
	35.7 Prevention
		35.7.1 Public Health Agency
	References
36: Campylobacteriosis
	36.1 Aetiology
	36.2 Burden
	36.3 Epidemiology
		36.3.1 Source
		36.3.2 Modes of Human Infection
		36.3.3 Campylobacter Infection in Birds
		36.3.4 Campylobacter Contamination of Broiler Meat
	36.4 Symptoms
		36.4.1 Campylobacteriosis in Human
		36.4.2 Foodborne Outbreaks
		36.4.3 Contact Borne
	36.5 Diagnosis
	36.6 Control
	36.7 Treatment
	References
37: Listeriosis
	37.1 Aetiology
	37.2 Epidemiology
		37.2.1 Infection in Animals
		37.2.2 Poultry
	37.3 Pathogenesis
	37.4 Listeriosis in Human
		37.4.1 Factors Associated with Listeriosis
	37.5 Contamination of Foods and Outbreaks
	37.6 Diagnosis
		37.6.1 Clinical Diagnosis
		37.6.2 Laboratory Diagnosis
			37.6.2.1 Cultural and Histopathological
			37.6.2.2 Biological Test
			37.6.2.3 Serological
			37.6.2.4 Nucleic Acid-Based Tests
	37.7 Treatment
	37.8 Control in Animals
	37.9 Control and Prevention in Humans
	References
38: Bacillus cereus
	38.1 Aetiology
		38.1.1 Spores
		38.1.2 Pathogenesis
		38.1.3 The Phylogenetic Groups
	38.2 Symptom
	38.3 Prognosis
	38.4 Diagnosis
	38.5 Prevention
	References
39: Foodborne Parasites
	39.1 Risk Management
	References
40: One Health
	40.1 The Concept
	40.2 The Objective
	40.3 Definition
		40.3.1 Understanding the `Drivers´ and Sectors
	40.4 Ecology and Evolution
		40.4.1 Land Use Change, Extractive Industries and Zoonoses
		40.4.2 Increasing Demand of Animal Produce for the Expanding Global Population
		40.4.3 Increasing Demand for Food and Antimicrobial Resistance (AMR)
		40.4.4 Import of Wildlife and Other Products
		40.4.5 Climate Change
		40.4.6 Natural Disaster: The Plague Epidemic in India (1994)
	40.5 How to Make This Concept Workable?
		40.5.1 Horizontal Integration of Sectors may be a Solution (Explained Below; Fig. 40.1)
	40.6 Advantage of One Health and Advocacy
	40.7 Methods of Disease Control and Prevention
	40.8 Conclusion
	References
Appendix A
	Specific Information Depending Upon the Questions and Demanded by Students Should Be Provided from Farm Records (Tables A.1, A...
Appendix B
	Websites, Software, and Apps Useful for Disease Surveillance and Intervention
	Important Epidemiological Software/Websites
	Certain Customised Apps
Glossary