Zoonoses and Livestock

Transcription

1 Hélène CHARDON Hubert BRUGÈRE Zoonoses and Livestock HEALTH SAFETY ANIMAL HEALTH Dossiers CIV-Zoonoses-UK-V5.indd 1 12/05/ :06

2 Zoonoses and Livestock Tour Mattei 207, rue de Bercy PARIS Published in May 2016 / Translated in May 2017 Layout : Jean-Baptiste Capelle - jb.capelle@legomenon.fr Translation: Lara Andahazy-Colo - laracolo@gmail.com 2 CIV-Zoonoses-UK-V5.indd 2 12/05/ :06

3 FOREWORD Zoonoses are infectious or parasitic diseases that are naturally transmissible between people and animals. Their importance for animal health and public health is well established and recognized. Despite considerable scientific progress understanding their mechanisms and the establishment of increasingly effective livestock protection systems (surveillance and control), the emergence and spread of zoonoses are still a major threat for human health. With the continued growth of the global population and the changes in people s modes of life and the environment, this risk is likely to increase significantly in coming years. Indeed, according to the World Organisation for Animal Health (OIE, the historical acronym of its former name Office International des Épizooties), 60% of the 1,400 human pathogens are of animal origin, and 75% of emerging animal diseases may be transmitted to humans. Given the health impact of zoonoses on people and livestock, and their economic and social impact, CIV (Viande, Sciences et Société) decided to publish a Dossier on this subject. In line with the scope of the collection, this Dossier offers a range of information allowing all interested parties to build or deepen their thinking on the subject. The Dossier aims to facilitate knowledge and understanding of societal issues related to livestock and meat value chains. To do so, it relies on scientific and legal publications, regulatory texts, and reports by institutions and official bodies. In Part One, this Dossier defines zoonoses and describes their ecology and epidemiology. Part Two presents public health protection systems when it comes to surveillance (living animals, meat and people) and control (prevention and eradication) for livestock in France, Europe and worldwide. Finally, given the global threat that zoonoses represent, Part Three covers risk factors, associated stakes and zoonoses evolution prospects (trends and strategic lines of control). This Dossier was designed and written by Hélène Chardon and Hubert Brugère. Hélène Chardon is a veterinarian and head of health safety and animal health projects at CIV; Hubert Brugère is a professor of food safety and industry at the École Nationale Vétérinaire de Toulouse (ENVT). CIV (Viande, Sciences et Société) would like to extend special thanks to Mr Stéphane Bertagnoli, professor of infectious pathologies at ENVT, Dr Paul Perie, veterinarian and member of the epidemiology committee of the Société Nationale des Groupements Techniques Vétérinaires, and Ms Anne Touratier, veterinarian adviser for health protection groups in France, for their attentive reading of and feedback on this Dossier. Pierre-Michel ROSNER Director, CIV 3 CIV-Zoonoses-UK-V5.indd 3 12/05/ :06

4 Zoonoses and Livestock CONTENTS Part 1 ZOONOSES: A General Overview 5 1. DEFINITIONS 1.1. Zoonosis Emerging or Re-Emerging Disease Mandatory Collective Prophylaxis Measures in the Event of Suspected or Confirmed Outbreaks 22 Part 3 ZOONOSES ON THE GLOBAL SCALE: Stakes and Prospects THE ECOLOGY AND EPIDEMIOLOGY OF ZOONOSES 2.1. Epidemiological Cycle Human Modes of Infection Frequency and Magnitude Among People 11 Part 2 PUBLIC HEALTH PROTECTION SYSTEMS for Zoonoses MONITORING 1.1. General Framework Live Animals Meat Humans CONTROL MEASURES: PREVENTION AND ERADICATION 2.1. Biosecurity for Livestock Rearing FACTORS IN THE EMERGENCE AND SPREAD OF ZOONOSES 1.1. Demographics and Urban Density Human Travel Agricultural Practices Trade Globalization Shifts in Human Non-Traditional Pet (NTP) Relations Climate Change EVOLUTION PROSPECTS 2.1 Tomorrow s Trends Strategic Lines to Control the Development of Zoonoses 31 Conclusion 34 Appendices 35 Bibliography 36 Glossary 38 Acronyms 39 Useful Links 39 4 CIV-Zoonoses-UK-V5.indd 4 12/05/ :06

5 Part 1 ZOONOSES: A General Overview 5 CIV-Zoonoses-UK-V5.indd 5 12/05/ :06

6 Zoonoses and Livestock Part 1 ZOONOSES: A General Overview 1. DEFINITIONS 1.1. ZOONOSIS The World Health Organization (WHO) and the European Union (EU) have since 1959 and 1992 respectively defined zoonoses as follows [29] 1 : Diseases and infections A zoonotic agent 2 may be a bacterium, a virus, a parasite, a fungus (dermatophyte) or a prion, de facto excluding poisoning and allergies, for example. that are transmitted An epidemiological link exists between animals and people. Diseases common to both animals and people are not zoonoses (e.g. botulism). naturally Diseases arising from experimental transmission are not zoonoses. from vertebrate animals to humans, Domestic or wild animals are potential vectors for zoonoses, even without clinical signs in the animals, not excluding the role of arthropod vectors. and vice versa. Zoonoses are inter-transmissible in both directions: people can transmit zoonotic agents to animals, which can in turn re-transmit these agents to people. In practice, however, transmission is more frequent from animals to people (zooanthroponosis) than from people to animals (anthropozoonosis). For various reasons, humans infected by animals might not re-transmit the zoonotic agent to susceptible human or animal hosts (e.g. trichinellosis, West Nile virus). In this case, people are an epidemiological dead end and we speak of dead-end zoonoses.in contrast, some zoonoses are of human origin. This is the case, for example, with bovine tuberculosis, the ancestor of the Mycobacterium bovis agent is thought to have been transmitted to cattle by humans during domestication (see Figure No. 1) [19]. Finally, some human diseases are caused by zoonotic agents that evolved from animal reservoirs. Following one or more mutations, the transmission of the agent became exclusively human (e.g. AIDS, smallpox, human influenza) (see Figure No. 1). To define zoonoses, some authors take zoonotic agents more into account. They insist specifically on their circulation between people and one or more vertebrate animals, irrespective of their consequences (illness or simply being a carrier) and infection modalities (by direct or indirect contact, through food, etc.). Zoonoses are in this case defined as diseases, infections or infestations triggered by transmissible agents (bacteria, viruses, parasites, fungi, or prions) existing in at least two vertebrate species, one of which is humans [9; 30; 31]. Studied in particular since the 19 th century and Pasteur s research on rabies and anthrax, proof of the existence of zoonoses goes as far back as prehistory (see Figure No. 1). According to the World Organisation for Animal Health (OIE), 60% of the 1,400 human pathogens are of animal origin, and 75% of emerging animal diseases may be transmitted to humans EMERGING OR RE-EMERGING DISEASE Among the many existing definitions (OIE, WHO, etc.), an emerging disease is defined as a disease whose real incidence is increasing significantly in a given population in a given region during a given period, compared to the habitual epidemiological situation for this disease [34]. This definition applies to human diseases as well as animal or plant diseases. While emerging diseases are primarily infectious in nature, they may also be other types of illnesses, or toxic, metabolic or other disorders [34]. For example, among humans, this includes metabolic disorders such as diabetes or illnesses associated with changes in lifestyles and consumption habits, such as obesity. Emerging diseases can be divided into four categories: A new disease caused by a previously unknown pathogen, for instance bovine spongiform encephalopathy (BSE), unknown prior to 1986 [15], see Factsheet pg. 25. A disease caused by a pathogen that mutated, altering its virulence or adapting to new hosts, 1. The numbers between square brackets correspond to the bibliographic reference listed on pages Underlined words can be found in the glossary on page CIV-Zoonoses-UK-V5.indd 6 12/05/ :06

7 Figure No. 1 A Few Major Zoonoses Throughout History Tuberculosis PREHISTORY Smallpox* (China, -600) 1 st plague epidemic ANTIQUITY ( th century) (Athens, -430) 1 st plague pandemic (542) 2 nd plague pandemic Tuberculosis, leprosy 1 st influenza epidemic* (12 th century) MIDDLE)-AGES (5 th -15 th centuries) ( ), 25 million deaths in Europe, or 30% population Yellow fever, influenza*, typhus, smallpox*, plague, etc. (America) MODERN ERA (15 th -18 th centuries) The Great Plague and smallpox* (Europe) Influenza* Tuberculosis bubonic plague pandemic CONTEMPORARY ERA (19 th century) Domestication, sedentarisation of people. Appearance of hygiene, wound treatment, 1 st health measures. Retreat of medicine, science and hygiene. Rise of commercial trade, particularly maritime trade. Discovery of the New World. Increased trade (people, animals, plants). Massive rural exodus. Increase in insalubrious housing in cities, rudimentary hygiene conditions, poverty. Spanish influenza* H1N1 ( , 20 to 40 million deaths in Europe) Rabies, glanders, CONTEMPORARY ERA (20 th century) tuberculosis, plague AIDS* (1981) vcjd (BSE, 1996, 2001) Avian influenza H5N1 (1997, 2006) SARS ( ) Mexican influenza* H1N1 (2009) CONTEMPORARY ERA (21 st century) Ebola (2014, West Africa) Zika (2015, Brazil) Use of zoonotic agents as biological weapons. 1881: Law on health measures for animal diseases. 1901: Creation of the Departmental Veterinary Services (France). 1924: Creation of the OIE. Population growth and increased urban concentration, changes in agricultural practices, globalization and rise in trade, development of antibiotic resistance, shift in human non-traditional pet relations, etc. * Not zoonotic, but of animal origin Note: Presented here are zoonoses whose emergence is documented in historical texts. for instance the avian influenza virus H5N1. The genetic properties of the highly pathogenic H5N1 virus evolve constantly. The risk of introducing this virus and of an epizootic is always present. Similarly, the pandemic influenza A H1N1 virus (2009) is a new virus because it presents a never before seen combination of swine, bird and human influenza virus genes. We can also note the case of zoonotic bacteria, such as Campylobacter, that can acquire antibiotic-resistant genes thereby making them difficult to treat among people exposed through food [10]. A disease that already exists in an exotic country or region and that spreads to a new region where it had not previously been found, for instance bluetongue disease (BTD). Serotype 8 of this virus spread in Northern Europe in 2006, whereas this region had previously been untouched. A disease that exists in an endemic state in a given region but has been present in low levels among a given population for years. A specific event favouring its spread and manifestation may sharply increase its incidence and be the source of its emergence in the strict sense, for instance Q fever caused by Coxiella burnetii in 2007 in the Netherlands. Emerging diseases are not systematically zoonoses. However, within emerging diseases, zoonoses hold a specific position and their magnitude is tending to increase mechanically. The frequency of emerging diseases has been on the rise since 1940, with a spike in the 1990s, as a result of both better detection and greater trade intensity. Between 1940 and 2004, nearly 330 new infectious diseases were discovered, 60% of which zoonoses of which 70% from wild animals [23]. Re-emerging diseases, for their part, are defined as diseases that had already been emerging diseases and that return in the same region and same population [34]. This means that the emergence of the disease had spiked in this population and region at a given 7 CIV-Zoonoses-UK-V5.indd 7 12/05/ :06

8 Zoonoses and Livestock Part 1 time. The control measures set up at the time had de facto caused a sharp reduction in the incidence or even the eradication of the disease and the loss of its status as an emerging disease. However, under specific circumstances, its incidence may once again increase significantly. This has been the case with bovine tuberculosis in France since 2010 (see Sidebar No. 1). 2. THE ECOLOGY AND EPIDEMIOLOGY OF ZOONOSES Currently in France, livestock-related zoonoses are few in number, primarily: Table No. 1 Main Zoonotic Agents by Farmed Mammal Species [19] CATTLE BACTERIA VIRUSES PARASITE/PRION/DERMATOPHYTE Bacillus anthracis (anthrax*) Brucella abortus (brucellosis*) Campylobacter jejuni (campylobacteriosis*) Coxiella burnetii (Q fever*) Leptospira (leptospirososis*) Listeria monocytogenes (listeriosis*) Mycobacterium bovis, caprae, tuberculosis (tuberculosis*) Salmonella (salmonella*) E. coli O157:H7 (haemorrhagic colitis, hemolytic uremic syndrome*) cowpox virus pseudocowpox virus bovine papular stomatitis rabies virus (rabies*) vesicular stomatitis virus Rift Valley fever virus Taenia saginata (teaniosis*) Toxoplasma gondii (toxoplasmosis*) BSE prion (CJD*) Trichophyton verrucosum/ Trichophyton mentagrophytes (ringworm*) SHEEP & GOATS BACTERIA VIRUSES PARASITE/PRION/DERMATOPHYTE Bacillus anthracis (anthrax*) Brucella melintensis (brucellosis*) Campylobacter jejuni (campylobacteriosis*) Coxiella burnetii (Q fever*) Erysipelothrix rhusiopathiae (erysipeloid*) Listeria monocytogenes (listeriosis*) Mycobacterium bovis, caprae (tuberculosis*) Salmonella (salmonella*) parapoxvirus (contagious ecthyma*) rabies virus (rabies*) vesicular stomatitis virus various arboviruses: louping-ill, Central European encephalitis, Nairobi sheep disease, Rift Valley fever Toxoplasma gondii (toxoplasmosis*) HORSES BACTERIA VIRUSES PARASITE/PRION/DERMATOPHYTE Bacillus anthracis (anthrax*) Brucella abortus (brucellosis*) Leptospira (leptospirososis*) Burkholderia mallei (glanders*) Burkholderia pseudomallei (melioidosis*) Salmonella (salmonella*) rabies virus (rabies*) vesicular stomatitis virus various arboviruses: Western encephalitis, Eastern encephalitis, Venezuelan encephalitis, West Nile virus, Tahyna virus, etc. Hendra virus Trichinella spiralis (trichinellosis*) Trichophyton equinum (ringworm*) SWINE BACTERIA VIRUSES PARASITE/PRION/DERMATOPHYTE Bacillus anthracis (anthrax*) Brucella suis (brucellosis*) Erysipelothrix rhusiopathiae (erysipeloid*) Leptospira (leptospirosis*) Mycobacterium avium (tuberculosis*) Salmonella (salmonella*) Streptococcus suis hepatitis E virus rabies virus (rabies*) vesicular stomatitis virus swine vesicular disease virus encephalomyocarditis virus various arboviruses: Japanese B encephalitis, etc. flu virus Nipah virus Taenia solium (taeniosis*) Toxoplasma gondii (toxoplasmosis*) Trichinella spiralis (trichinellosis*) Sarcoptes scabiei (sarcoptic mange*) Microsporum nanum (ringworm*) * Illness caused by the zoonotic agent. 8 CIV-Zoonoses-UK-V5.indd 8 12/05/ :06

9 Sidebar No. 1 A Re-Emerging Disease in France: The Case of Bovine Tuberculosis Tuberculosis was a major scourge for cattle rearing during the first half of the 20 th century, causing significant economic losses (meat and milk). At the time, bovine tuberculosis was considered to be an emerging disease. Since 1950, various control measures have been implemented: annual screening through tuberculin testing of all livestock and during movement from one farm to another to detect ill animals and carriers, the (partial or total) slaughter of infected herds, and the inspection of carcasses in slaughterhouses. Thanks to these measures, the percentage of infected herds was brought down to less than 0.1%, allowing France to be officially declared to free of bovine tuberculosis since zoonoses of bacterial origin: brucellosis, tuberculosis, Q fever, anthrax, campylobacteriosis, listeria, salmonella, enterohemmoragic E. coli, leptospirosis; zoonoses of viral origin: rabies (Guyana), parapoxviruses, hepatitis E; zoonoses caused by parasites: taeniosis, toxoplasmosis, trichinellosis, even sarcoptic mange; zoonoses caused by prions: BSE and variant Creutzfeldt-Jakob disease; and zoonoses caused by a dermatophyte (fungus): ringworm EPIDEMIOLOGICAL CYCLE The ecology of zoonoses involves several components: the zoonotic agent, one or more hosts, a reservoir and sometimes a vector [16]. Zoonotic agent: etiological agents of zoonoses characterized as a transmissible agent that is not restricted to a single host and can cause an infection or infestation (with or without manifestation of the clinical disease) in at least two vertebrate species, one of which is humans (see Table No. 1). Host: living being that carries a pathogen under natural conditions. Reservoir: may be defined as an ecological system in which a zoonotic agent survives indefinitely. This may refer to vertebrates, invertebrates (e.g. arthropods), and also the milieu itself (e.g. soil). Vector: a living being that, in ecological relationships, acquires a pathogen from a living host and then transmits it to another host. The vector is an arthropod (see Figures Nos. 2.2 and 2.3). An inanimate vector, also However, since 2010, outbreaks of bovine tuberculosis have happened in approximately fifteen Departments in France, notably due to cross contam ination between cattle (primary reservoir) and wildlife (deer, boars, badgers). Indeed, wildlife is a secondary reservoir for the bacteria causing this disease (Mycobacterium bovis). This situation is also the result of a lightening of prophylaxis regimes, changes in herd size between 1965 and 2000, and alterations in animal rearing practices such as longer pasturing times for suckling herds, etc. Given the significant change in its incidence, bovine tuberculosis is now classified as a re-emerging disease in France and consequently requires greater surveillance (see Part 2). called a vehicle, may serve as the support for the spread of the agent (e.g. air, water). The epidemiological cycle of a zoonosis therefore involves at least one animal species and humans. However, it can sometimes be very complex and include, in a given environment, many receptive animal species, various essential or potential vectors, and humans HUMAN MODES OF INFECTION Zoonotic agents may be excreted by animals in their respiratory, digestive, genital, etc. secretions or be present in foods of animal origin (meat, milk, eggs). The three main pathways of transmission to humans are, thus, direct or indirect contact, food and inoculation by an arthropod vector. Contact with animals, animal products or a contaminated environment (see Figures Nos ). Direct contact or close proximity: Transmission to humans can occur through contact with skin or mucous membranes (e.g. brucellosis from contact with aborted foetuses or placentas contaminated by B. abortus, see Factsheet pg. 23), orally (dirty hands are often the source of this type of contamination), via the respiratory route (e.g. Q fever from inhaling infectious dust or aerosols contaminated by C. burnetii) or even from skin punctures in the event of a bite or scratch (e.g. rabies) or following an injury (e.g. tuberculosis, erysipeloid). Some zoonoses are viewed as occupational because they are contracted during the normal performance of professional duties in jobs involving recurrent contact with living animals, cadavers, carcasses and various animal products. This is the case for stock farmers, 9 CIV-Zoonoses-UK-V5.indd 9 12/05/ :06

10 Zoonoses and Livestock Part 1 Figure No. 2 Mechanisms of Action for Zoonosis (1. General, 2. Vector-Borne, 3. Dead-End ) 1 2 FAVOURABLE ENVIRONMENT SUSCEPTIBLES HOSTS (animals/people) VECTOR ZOONOTIC AGENT SUSCEPTIBLES HOSTS (animals/ people) ZOONOTIC AGENT ENVIRONMENT risk for people 1. Components contributing to the emergence and propagation of zoonoses. 2. The presence of a vector is indispensible in the case of strictly vector-borne zoonoses. 3 ANIMALS PEOPLE TRANSMISSION OF THE ZOONOTIC AGENT VECTOR Mechanism of action for dead-end zoonoses (humans = epidemiological dead-ends ) without possible re-transmission to people or animals. slaughterhouse staff, renderers and veterinarians. These zoonoses such as brucellosis, tuberculosis and anthrax are thus included on the list of occupational diseases (Decrees of and ) [20]. Indirect contact: via a medium, without direct contact with animals. The medium can be the air, soil or even water. This is the case, for example, with bathing water contaminated by enterohemmoragic E. coli [11] or leptospirosis. In this case, we speak of leisure zoonoses. Food: In rare cases, food may harbour pathogenic microorganisms or parasites. Eating these foods may present a risk for consumer health, under certain consumption conditions and for certain people (see 2.3). Regarding transmission to humans, these foods may be merely a vehicle. In the case of bacteria, these foods may also be where they multiply, allowing them to attain a dangerous threshold. For instance, salmonella are the agents most often incriminated in France in collective food poisoning (CFP) outbreaks for all foods combined. Salmonella s natural habitat is the intestines of many animal species and humans (usually asymptomatic carriers). In poultry, for example, carcasses may pick up surface contamination from salmonella present in the digestive tube during slaughter and preparation. As these bacteria are easily destroyed by heat, the most frequently incriminated foods are those eaten raw or after moderate cooking. However, the risk to consumers of cross contamination between raw and cooked foods during meal preparation [6] must not be ignored. Other foods may be the source of zoonoses, such as vegetables grown in soil contaminated by animals (Toxoplasma gondii) or contaminated drinking water (enterohemmoragic Escherichia coli, see Figure No. 3). According to the WHO, foodborne zoonoses are said to be the cause of 2 billion illnesses per year worldwide and responsible for 2 million deaths [32; 33]. Infection by a vector arthropod: zoonotic agents may in some cases be transmitted by vector arthropods such as mosquitoes, fleas, flies, midges, lice or ticks. This is the case with West Nile virus (see Figures Nos CIV-Zoonoses-UK-V5.indd 10 12/05/ :06

11 and 4). Migratory birds form the reservoir for the virus. It is spread through the bite of a Culex mos quito: after having bitten infected birds, mosquitoes transmit the virus to people or horses. Most mammals, including people and horses, are epidemiological dead ends. Horses seem especially sus ceptible and are often seen as indi cative of the virus s circulation [25]. In addition, among people, cases of the spread of a zoonotic agent by blood transfusion or during organ transplants have been described (see Figure No. 4) FREQUENCY AND MAGNITUDE AMONG PEOPLE Figure No. 3 Transmission of enterohemorrhagic Escherichia coli to humans via food [11] enterohemorrhagic Escherichia coli (EHEC) bacteria DIGESTIVE TRACT OF CATTLE (main reservoir for EHEC) contamination during milking contamination of carcasses during preparation contamination by irrigation water and manure meat fruits and vegetables milk and dairy products The frequency of outbreaks varies according to the zoonosis and geographic area. For example, leptospirosis is often seen in most countries of the world. Other zoonoses are less common or more localized, such as glanders and the plague. The importance of zoonoses among people is defined in function of their frequency (see Table No. 2), medical severity, and for some their economic fallout. Let us also note that some populations are more sus ceptible than others. According to ANSES, a vulnerable faecal contamination drinking water population refers to people who have a higher than average probability of developing, after exposure to the danger, symptoms of the disease or serious forms of the illness, for instance: children and the elderly in the event of expo sure to enterohemorrhagic E. coli (risk of contracting hemolytic uremic syndrome); the immunocompromised: people with chronic illnesses or undergoing medical treatment that causes decreased immunity; in the event of exposure to Lis- Figure No. 4 The Epidemiological Cycle of West Nile Virus Birds Primary enzootic cycle Maintenance vector : mosquitoes Maintenance vector : "Incidental" hosts mosquitoes person to person (blood transfusion, organ transplantation, transplacental transmission, possibly via breast milk) Birds Source : Bridge vector : mosquitoes 11 CIV-Zoonoses-UK-V5.indd 11 12/05/ :06

12 Zoonoses and Livestock Part 1 Table No. 2 Major Infectious Zoonoses Among People in France and Around the World [source 20] ZOONOSIS GLOBAL FREQUENCY PRESENCE IN FRANCE MAIN ANIMAL SPECIES INVOLVED brucellosis +++ very rare (except B. suis) all mammalian species anthrax +++ yes all mammalian species Eastern, Western and Venezuelan encephalitis + no horses yellow fever + no monkeys Lassa fever + no rodents zoonotic Influenza H5N1 ± no all species of birds leptospirosis ++ yes all mammalian species glanders + no horses plague + no all mammalian species psittacosis ++ yes all species of birds rabies +++ no all mammalian species salmonella ++++ yes all mammalian species tuberculosis +++ yes all mammalian species Note: global frequency represented by signs ranging from + to ++++ teria monocytogenes, these people are likely to develop forms of meningitis; and pregnant women with exposure to Toxoplasma gondii (risk of death of the embryo, miscarriage or congenital defects) or exposure to Listeria monocytogenes (risk of miscarriage or premature birth). Finally, among the population, there are sub-populations with greater risk of being exposed to contact with animals, for instance people exposed through their jobs (see above). The scope of circulation of a zoonotic agent between animals and people, and especially within the human population, makes it possible to distinguish between three major categories of zoonoses (see Table No. 3) [31]. A given zoonotic disease does not require protection protocols of the same magnitude for people and for animals. In animal health, a zoonotic disease will be seen as very important if it triggers serious or high-incidence illness among people and/or animals, and also if it affects animals whose products are traded between different countries. However, if it easily diagnosed and treated, little or not contagious, and infrequent, the same illness among people will not be the subject of priority preventive action. This is the case, for instance, with brucellosis in France for which there is mandatory prophylaxis among cattle and monitoring of miscarriages among livestock but for which there are no systematic screening measures among humans (see Factsheet pg. 23, Part 2). This heterogeneity in the impacts of zoonoses on human and animal health partially explains the policies implemented for animals and humans in regard to zoonoses (see Part 2). 12 CIV-Zoonoses-UK-V5.indd 12 12/05/ :06

13 Table No. 3 Zoonoses and the Various Types of Transmissible Diseases [31] TYPE OF TRANSMISSIBLE DISEASE communicable pathogen among animals (one or more species) no natural transmission to people animal pathogen capable of primary infection without secondary inter-human transmission transmission (direct or indirect) only from an animal reservoir, no natural inter-human transmission (excluding modern technologies such as transplantation, blood transfusion, etc.) animal pathogen capable of primary and secondary infections (a few cycles) transmission possible from an animal reservoir and between people animal pathogen capable of primary infection with many secondary cycles person-to-person transmission (including by vector), responsible for most cases among humans exclusively human-to-human pathogen transmission, including by vector no natural transmission to animals EXAMPLES AND MODALITIES OF TRANSMISSION TO PEOPLE foot-and-mouth disease swine fever bluetongue disease rabies West Nile virus anthrax bovine spongiform encephalopathy bovine brucellosis M. bovis tuberculosis monkey pox virus Chagas disease yellow fever SARS-MERS malaria HIV measles smallpox STATUS R0: rate of reproduction of the disease among people Purely Animal Diseases Non-Extensive Zoonoses = dead-end zoonoses R0 = 0 Extensive Zoonoses R0 < 1 Extensive Zoonoses Significant Inter-Human Transmission R0 > 1 Strictly Human Disease whose origin is historically (and/or phylogenetically) animal, human or not yet known 13 CIV-Zoonoses-UK-V5.indd 13 12/05/ :06

14 Zoonoses and Livestock 14 CIV-Zoonoses-UK-V5.indd 14 12/05/ :06

15 Part 2 PUBLIC HEALTH PROTECTION SYSTEMS for Zoonoses 15 CIV-Zoonoses-UK-V5.indd 15 12/05/ :06

16 Zoonoses and Livestock Part 2 PUBLIC HEALTH PROTECTION SYSTEMS for Zoonoses 1. SURVEILLANCE 1.1. GENERAL FRAMEWORK Surveillance of zoonoses is done, among people and among animals, on two levels: Surveillance of known diseases (e.g. tuberculosis and brucellosis): A regulatory framework exists (see Table No. 4) and control measures are known and recognized (see Factsheets pgs ). Monitoring of new emerging phenomena: The goal is to spot any atypical event or abnormal situation, such as the appearance of clinical signs not described among animals, which could be the source of an emerg ing animal disease or even zoonosis. In this case, epidemiological and microbiological investigations are needed to set up a suitable regulatory arsenal and ad hoc control measures (see Sidebar No. 2). Until the research results come in, we rely on the precautionary principle to avoid or limit any propagation to other animals or to people. With hindsight, the measures taken during this initial period may seem excessive but the technical and scientific knowledge at the time did not provide any certainty. Without a sufficiently efficient disease control system (prevention and eradication) (see 2), surveillance is the main tool to ensure the country s health safety situation in regard to the danger in question. Surveillance provides data to inform risk management decisions. Hence the importance of new systems, notably on the national scale, such as the Plateforme Nationale de Surveillance Épidémiologique en Santé Animale (ESA Platform the French national platform for epidemiologic surveillance in animal health). Born from the reflections undertaken during the General Assembly on Health that was held in 2010 under the auspices of the Ministry of Agriculture, the ESA Platform was set up at the end of Its operational remit is to: participate in the elaboration and improvement of epidemiologic surveillance systems; Table No. 4 Main Regulations on Zoonoses and Zoonotic Agents WITHIN EUROPE Council Directive 64/432/EEC on animal health problems affecting intra-community trade in bovine animals and swine (notably covering tuberculosis and brucellosis). Council Directive 91/68/EEC on animal health conditions governing intra-community trade in ovine and caprine animals (notably covering brucellosis). Regulation 999/2001/EC laying down rules for the prevention, control and eradication of certain transmissible spongiform encephalopathies (of which BSE). Directive 2003/99/EC on the monitoring of zoonoses and zoonotic agents: zoonoses, zoonotic agents and the associated antimicrobial resistance are monitored; food-borne outbreaks are investigated using epidemiological studies; and the necessary data may be gathered in the European Union in order to evaluate trends and sources. Regulation 854/2004/EC laying down specific rules for the organization of official controls on products of animal origin intended for human consumption. Regulation 2073/2005/EC on microbiological criteria for foodstuff. Regulation 1069/2009/EC laying down health rules as regards animal by-products and derived products not intended for human consumption. Regulation (EU) 2016/429 on transmissible animal diseases and amending and repealing certain acts in the area of animal health. Applicable in April 2021 (see Sidebar No. 5). (cont.) 16 CIV-Zoonoses-UK-V5.indd 16 12/05/ :06

17 Table No. 4 Main Regulations on Zoonoses and Zoonotic Agents IN FRANCE Order of 3 December 1990 setting the animal health measures regarding bovine spongiform encephalopathy. Order of 17 March 1992 on the conditions that must be met by slaughterhouses handling food animals for the production and marketing of fresh meat and setting the health inspection conditions for these establishments. Order of 9 June 2000 setting the animal health measures regarding bovine spongiform encephalopathy. Order of 15 September 2003 setting the technical and administrative measures regarding collective prophylaxis and animal health measures for tuberculosis in cattle and goats. Order of 22 April 2008 setting the technical and administrative measures regarding collective prophylaxis and animal health measures for bovine brucellosis. Decree No of 30 June 2012 on the general provisions organizing prevention, monitoring and control of category one and category two health risks (see Sidebar No. 3). Amended Order of 13 August 2012 on the creation of a pilot departmental scheme to monitor Q fever on cattle, sheep and goat livestock operations. Order of 10 October 2013 setting the technical and administrative measures regarding collective prophylaxis and animal health measures for ovine and caprine brucellosis. Order of 24 September 2015 establishing health inspections on livestock units. facilitate the centralization, optimization and sharing of health data; and contribute to the analysis and dissemination of health data. The ESA Platform s priority topics cover, among other things, zoonoses such as bovine tuberculosis, brucellosis, swine flue virus and avian flu. For each of these, a specific system exists, such as Sylvatub for bovine tuberculosis. Set up by the ESA Platform and funded by the Ministry of Agriculture since 2011, Sylvatub monitors bovine tuberculosis in all departments in France with different levels of surveillance based on risk. For instance, to better grasp the role of badgers Sidebar No. 2 An Example of a Zoonosis Research Project Given their major repercussions on public health, animal health, value chain economics, etc., zoonoses are currently the subject of active research programmes. This is especially true of zoonoses transmitted by ticks. As a reminder, ticks are known for being the second largest vector of illnesses for people and animals worldwide, behind mosquitoes, and the largest in Europe. Thus, in response to the upsurge in the emergence of human and animal diseases linked to these arthropods, a consortium, consisting of the Institut National de la Recherche Agronomique (INRA, French national agronomic research institute), ANSES, the École Nationale Vétérinaire d Alfort (Alfort national veterinary school), the PathoQuest company and the Institut Pasteur, is conducting research on the pathogens transmitted by these vectors. The research team extracted all the ribonucleic acid (RNA) from the ticks (Ixodes ricinus) to identify the micro-organisms present in the ticks. They thus revealed the unexpected presence of bacteria such as Borrelia miyamotoi and Neoehrlichia mikurensis both of which are associated with high fevers and new species of parasites, Babesia and Theileria, which could potentially be associated with diseases. Many new viruses identified in these ticks are being characterized. Researchers are currently working to determine the pathology of each of the identified bacterial, viral or parasitic species. These micro-organisms will eventually be fully sequenced. Ultimately, this project could make it possible to develop preventive tools and future screening and diagnostic tests. 17 CIV-Zoonoses-UK-V5.indd 17 12/05/ :06

18 Zoonoses and Livestock Part 2 in transmitting tuberculosis to cattle, traps have been set up around areas where there have been outbreaks of bovine tuberculosis and surveillance systems for animals found dead along the roadsides have been set up. This surveillance confirmed cases in boars, badgers and deer. This system thus reveals infection rate trends among susceptible wildlife in areas where tuberculosis is present. It is a sign of the ESA Platform s vitality (www. plateforme-esa.fr). Within Europe, annual surveillance data on zoonoses and zoonotic agents are centralized by member-states and transmitted to the European Commission and then to the European Food Safety Agency (EFSA). Every year, the EFSA and the European Center for Disease Prevention and Control (ECDC) publish a summary report on trends and sources of zoonoses, zoonotic agents and antimicrobial resistance in Europe. Thus, in 2013, as in previous years, zoonotic infections affecting humans were mainly six food-borne or orally transmitted zoonoses, all foods combined (campylobacteriosis, salmonella, yersiniosis, EHEC infections, listeriosis and echinococcosis). When trichinellosis and brucellosis are included, in 2013, food-borne zoonoses accounted for 99.6% of the 314,430 cases among humans caused by the thirteen sources of zoonoses reported in Europe. The remaining cases (0.4%) were caused by zoonoses transmitted to humans via other means (Q fever, West Nile virus, M. bovis tuberculosis, tularaemia and rabies) [14; 17]. When the information gathered during routine monitoring is not sufficient, the European Commission may set up coordinated surveillance programmes for one or more zoonoses and/or one or more zoonotic agents, particularly when specific needs are noted among European Union member States [18]. Internationally, the OIE pilots a data collection system. It relies on: An early warning system destined to inform the international community of relevant epidemiological events in the 180 OIE member countries, via alerts. A surveillance system tracking illnesses on the OIE list over time, including zoonoses such as bovine and ovine brucellosis, bovine tuberculosis, Q fever, rabies, avian influenza, trichinellosis and BSE. All notifications to the OIE are communicated to the World Trade Organization (WTO) for the establishment of measures in the framework of international commercial trade. Indeed, the aim is to limit or prevent any spread of the zoonotic agent in question via animals or animal products. Official recognition of member countries health status: Of major importance in international trade, it has been one of the most important legal ties between the OIE and the WTO since The OIE s official health status recognition process is a voluntary process for countries, and currently applies to six diseases, including one zoonosis BSE. The loss and recovery of official health status are managed objectively and transparently, in compliance with an official standardized procedure. To ensure maximal control of zoonoses, surveillance measures address the various links in the chain, specifically live animals, food and people LIVE ANIMALS Daily Surveillance on Livestock Farms Farmers monitor the state of their animals health daily; they know and master most of the care their animals need. In the event of atypical or unusual clinical signs or abnormal situations (mortality rate higher than the farm s typical threshold, for example), they call their veterinarians. For instance, in the specific case of BSE, farmers keep a close watch for any neurological troubles that could point to this animal disease or the presence of at-risk animals on their farms (animals over 48 months of age found dead on the farm, that were in accidents or slaughtered as emergencies) [15]. Veterinarians and farmers are therefore essential players in monitoring the appearance of emerging animal diseases, and particularly emerging zoonoses. The health network also takes on primordial importance, as does efficient coordination between the farm veterinarians (who signal their suspicions), the departmental coordinating veterinarians (who confirm suspicions) and the departmental veterinary services (that apply animal health measures). Indeed, early detection and rapid screening ensure effective management of this type of illness Health Visits On-farm health visits are mandatory in the cattle (since 2005), poultry (since 2013), pig (since 2015), sheep and goat (in 2017) value chains, either annually or every two years depending on the case. They are conducted by the farm health veterinarian under the responsibility of the Direction départementale de la protection des populations (DDPP, departmental offices for the protection of populations) in the department where the farms are located. These visits, conducted on the basis of a questionnaire and a guide drawn up on the instruction of the Ministry of Agriculture, focuses notably on animal health man agement, animal health protection, management of veterinary pharmaceu 18 CIV-Zoonoses-UK-V5.indd 18 12/05/ :06

19 ticals, etc. The aim is to collect data and/or raise farmers awareness on specific topics of epidemiological interest or on various animal health aspects such as maintaining optimal biosafety on farms (see 2.1) Ante Mortem Inspections in Slaughterhouses These inspections of animals on their arrival at the slaughterhouse by veterinary agents aim notably to ensure that the animals are in good health and that their physiological state will not result in any anomalies in the meat. For instance, any animal presenting a clinical sign evoking BSE during ante mortem inspection is systematically pulled out of the slaughter chain and euthanized [6; 15] MEAT Post Mortem Inspections in Slaughterhouses After slaughter, the whole carcass and viscera are individually and minutiously inspected by the veterinary services in compliance with Regulation No. 854/2004/ EC. At this stage, a certain number of scientific tests are systematically run and notably concern zoonoses of parasitic origin [6]: tape worm larvae on cattle and pig carcasses (visual examination, and when needed after muscle incision); trichinella larvae on the carcasses of horses, pigs raised in the open air, cull breeding swine (sows/boars) and boars (muscle samples for laboratory analysis; for pork pigs kept in controlled husbandry buildings, only a sample is tested (on the order of 1 per 1,000 slaughtered)). As a reminder, only carcasses that show no lesions or alterations and for which all results are favourable are stamped with a health mark. These carcasses may then be destined for human consumption DGAL Surveillance Plans The Direction Générale de l Alimentation (DGAL, French general directorate for food) conducts annual testing the main objective of which is to estimate contamination in a given production (target population) and thereby assess consumers level of risk exposure. The sampling is representative of the target population and samples are collected randomly from within this population (Regulation No. 882/2004/EC). In compliance with Directive 2003/99/EC, the search for zoonotic agents in all links of the food chain is integrated into these plans with [28]: For beef: testing for Shiga toxin-producing E. coli. Between 2007 and 2013, the contamination rate of refrigerated ground meat is estimated to have been between 0.1% and 0.4%, and that of frozen ground meat is estimated at between 0.3% and 0.5% (see EHEC factsheet, pg. 23). For pork: testing for Salmonella spp., Echinococcus granulosus and Toxoplasma gondii. In 2013, the contamination rate is estimated to have been 1.0% at most for Salmonella spp. (dry sausage) and E. granulosus (pork viscera); 3.0% for T. gondii in pigs raised in above-ground systems and 6.3% in pigs raised in open-air systems (meat) Testing of Animals and Animal Products on Import Border inspection post (BIP) agents examine all live animal and animal product imports. They verify the Sidebar No. 3 Regulated Illnesses in Animals French law distinguishes between two types of regulated animal illnesses (Decree of 30 June 2012 and Order of 29 July 2013): Category 1 health dangers (formerly called maladies réputées contangieuses or MRCs, diseases considered to be contagious): dangers whose manifestations have serious consequences and that require, in the general interest, regulatory control. This is the case with brucellosis, botulism and BSE, for instance. The dangers entering into this category are all the subject of mandatory reporting, prevention, surveillance and eradication measures [19]. Category 2 health dangers: dangers for which it may be appropriate, in the collective interest, to define regulatory measures or officially recognize the actions taken by certain production chains. This is the case with glanders and trichinellosis, for instance. These lists are regularly updated. In the event of emerging diseases, it is possible to provisionally list an emerging danger for three years in category 1, until the elements necessary to determine its definitive classification can be assembled [19]. 19 CIV-Zoonoses-UK-V5.indd 19 12/05/ :06

20 Zoonoses and Livestock Part 2 Figure No. 5 Example of the Information Gathering and Exchange System for Food-Borne Illnesses: Listeria Unit A DDCCRF private or public bio-medical analysis laboratories patient clinicians SB patient record MR FQ ARS MR MR FQ DGCCRF CNR InVS DGS DGAL SB SP A SB food record LNR SB SP DDPP A public or private food analysis laboratories A : Alert MR : Mandatory Reporting SP : Surveillance Plan FQ : Food Questionnaire SB : Strains of Bacteria Listeria Unit ARS : Agence régionale de santé (regional health agency) DGAL: Direction Générale de l Alimentation (general directorate for food, France) DDPP: Direction Départementale de la Protection des Populations (departmental office for population protection, France) Source : Institut Pasteur DGCCRF / DDCCRF: Direction Générale de la Concurrence, de la Consommation et de la Répression des Fraudes (French general directorate for competition, consumption and fraud prevention) / Direction Départementale de la Concurrence, de la Consommation et de la Répression des Fraudes (departmental directorate for competition, consumption and fraud prevention, France) DGS: Direction Générale de la Santé (directorate general for health, France) NRL: National Reference Laboratory NCR: National Centre of Reference InVS: Institut de Veille Sanitaire (French institute for public health surveillance) origin authorization (country, region, establishment) and accompanying health certificates. Imported lots are subject to a monitoring plan designed to detect residues, pathogenic agents and other substances that present a danger for people, animals and the environment. In 2013, 1,444 lots of animal products were subjected to random testing out of a total of 42,068 imported lots. The sampling rate was 3.4% (higher than the 3% set by the memorandum on the subject). In 2013, 11 lots were non-compliant and consequently rejected, mostly fishery products [28] HUMANS It is necessary to collect cross sectional data on the emergence of zoonoses and zoonotic agents in animals and people, as well as in foodstuffs and animal feed, to determine zoonosis trends and sources Reportable Diseases in People In France, certain diseases are subject to surveillance under the Public Health Code (Articles L , R to 5, D to 7). All health care professionals (private and hospital practitioners, biologists in public and private medical laboratories) are obliged to report these diseases to the health authorities when they are diagnosed. This procedure concerns more than thirty human diseases such as collective food poisoning (CFP), some of which are food-borne zoonoses (e.g. salmonellosis). The goal is to monitor changes in the incidence of these diseases, detect clusters of cases and epidemiological trends, and if necessary intervene early to limit the spread of certain infectious agents. Thus, when they suspect or diagnose one of these diseases in patients, doctors and biologists must immediately report it to the public health inspector medical doctor at the Agence Régionale de Santé (ARS, regional health agency) for their place of practice. This procedure makes it possible to set up individual or collective preventive action and investigations such as: epidemiological investigations aiming to identify cases and describe the epidemic then analyse the results of the survey to confirm the cause; microbiological surveys aiming to identify the food and agent responsible for the problem; health surveys aiming to identify events that triggered the contamination and/or multiplication of pathogenic agents in food. 20 CIV-Zoonoses-UK-V5.indd 20 12/05/ :06

21 All of the collected data are then centralized by the Institut de Veille Sanitaire (InVS, French institute for public health surveillance) that analyses the data on the national scale [6] Antibiotic Resistance Surveillance Networks In compliance with Directive 2003/99/EC, zoonoses and zoonotic agent surveillance programmes have been set up in France (see Table No. 4). This is the case with surveillance networks looking specifically at bacterial resistance to antibiotics [10]: The Salmonella network: Salmonella are one of the main causes of CFP due to the consumption of foods of animal origin. This network collects strains of Salmonella of non-human origin (isolated in food, the environment or on livestock operations) to determine the serotype and study their sensitivity to antibiotics. The Résapath network: This network collects information from antibiograms of bacteria isolated from cattle, sheep, goats, horses, pigs and poultry in 94 departments. These data are compared to the data from 16 surveillance networks looking at bacterial resistance among people in cities and hospital settings, as part of the Observatoire National de l Épidémiologie de la Résistance Bactérienne aux Antibiotiques (ONERBA, French national observatory of the epidemiology of bacterial resistance to antibiotics). This integration allows for constant pooling of the human and animal data obtained, which is particularly important when efforts to reduce resistance levels Sidebar No. 4 International Cooperation [20] must necessarily be combined. For instance, multidrug resistance in E. coli is found in most animal production sectors, in particular for strains resistant to 3 rd and 4 th generation cephalosporins (C3G/C4G). Note: On the European level, the European Medicines Agency centralizes all data (ESVAC project). Despite all these surveillance measures, zero risk of a zoonosis occurring, whether emerging or not, does not exist. Therefore, disease control measures are implemented with animals and animal products in order to protect animal health and public health as best as possible. 2. DISEASE CONTROL MEASURES: PREVENTION AND ERADICATION 2.1. BIOSECURITY FOR LIVESTOCK REARING On livestock operations, as in assembly centres, measures are taken by sector professionals to lessen the propagation of agents that may already be present within the operation (internal biosafety) and to avoid the introduction of new infectious agents (external biosafety). These measures may be general in nature (hygiene of the premises, equipment, animals and procedures) or pathogen-specific. This is the case, for The major zoonoses are often present in several regions of the world. Joint inter-state actions are therefore needed. This cooperation is mainly ensured by the WHO, FAO and OIE with the help of the World Bank and a United Nations programme (UNDP). The WHO has collaborating centres to study global public health problems and specific zoonoses (rabies, plague, etc.). In this framework, the WHO disseminates information and establishes disease control programmes. It thus drew up International Health Regulations for diseases that require animals to be isolated for a period, two of which are zoonoses: plague and yellow fever. The WHO notably helps set up these programmes in the countries concerned. A new step was taken in 2008 with the establishment of the One World, One Health concept promoted by the WHO, FAO and OIE that highlights the need for collaboration between medical and veterinary public health structures both nationally and globally. Recent years have seen the retreat of certain major zoonoses such as the plague, yellow fever and glanders. These positive results are the outcome of the abovementioned measures. However, even for these zoonoses, well-established outbreaks persist. Africa and Asia are still two major reservoirs of zoonoses, some of which currently considered to be exotic are potential threats for temperate regions. 21 CIV-Zoonoses-UK-V5.indd 21 12/05/ :06