BIODIVERSITY AND EMERGING INFECTIONS Paul-Pierre PASTORET World Organisation for Animal Health (OIE)

EMERGING INFECTIONS A COLLECTIVE NAME FOR INFECTIOUS DISEASES THAT HAVE BEEN IDENTIFIED AND TAXONOMICALLY CLASSIFIED RECENTLY IN HUMANS, IN THE FINAL QUARTER OF THE TWENTIETH CENTURY, MORE THAN 30 SUCH CONDITIONS WERE RECOGNISED

SEVENTY TO SEVENTY FIVE NEW EMERGING INFECTIONS ARE ZOONOTIC

TWO PARTNERS AN INFECTION/DISEASE IS THE RESULT OF THE INTERACTION BETWEEN TWO PARTNERS: THE PATHOGEN AND THE HOST. WE SHALL FOCUS ON MAMMALS AND VIRUSES.

MAMMALS ACCORDING TO WILSON and REEDER: IN MAMMAL SPECIES OF THE WORLD (2005), THERE EXIST 5,416 MAMMAL SPECIES THE ADVENT OF MODERN MOLECULAR TECHNIQUES HAS ALLOWED INCREASINGLY DETAILED COMPARISONS OF SPECIES LIMITS AND EVOLUTIONARY RELATIONSHIPS

MAMMAL SPECIES 2 THE INVENTORY OF MAMMAL SPECIES IN 1982 CONTAINED 4,170 SPECIES; THE INVENTORY IN 1993 CONTAINED 4629 SPECIES AS COMPARED TO 5416 IN 2005. MOST OF THE INCREASE IN NUMBER IS DUE TO TAXONOMIC REVISION, BUT A SIGNIFICANT PROPORTION IS DUE TO NEWLY DESCRIBED SPECIES

MAMMAL SPECIES 3 SOME SPECIES ARE EXTINCT, OTHERS ARE ENDANGERED CITES: CONVENTION ON INTERNATIONAL TRADE IN ENDANGERED SPECIES OF WILD FAUNA AND FLORA. OTHER SPECIES ARE EXPANDING THEIR RANGE OR ARE INVASIVE. THE SITUATION IS PERMANENTLY EVOLVING

IT IS TO SAY 20.6 % OF THE TOTAL AMOUNT OF MAMMAL SPECIES ORDER CHIROPTERA AMONG MAMMAL SPECIES, THERE ARE 1,116 BAT SPECIES BELONGING TO 202 GENERA; 49 NEW SPECIES HAVE BEEN RECOGNISED SINCE 1993 IT IS TO SAY 20.6 % OF THE TOTAL AMOUNT OF MAMMAL SPECIES

IT IS TO SAY 42% OF THE TOTAL AMOUNT OF MAMMAL SPECIES ORDER RODENTIA AMONG MAMMAL SPECIES, THERE ARE 2,277 RODENT SPECIES BELONGING TO 481 GENERA; 128 NEW SPECIES HAVE BEEN RECOGNISED SINCE 1993 IT IS TO SAY 42% OF THE TOTAL AMOUNT OF MAMMAL SPECIES

WILD MAMMALS BIODIVERSITY THE HOTSPOTS OF MAMMAL BIODIVERSITY ARE OBSERVED IN TROPICAL AREAS, SUCH AS SUB-SAHARAN AFRICA

BIODIVERSITY OF DOMESTIC MAMMALS THERE ARE MORE THAN 300 RECOGNISED DOG BREEDS WITH DIFFERENT GENETIC BACKGROUNDS THERE ARE APPROXIMATELY 700 CATTLE BREEDS THROUGHOUT THE WORLD MANY OF WHICH IN A CRITICAL STAGE (LESS THAN 100 BREEDING COWS)

SUSCEPTIBILITY TO INFECTIONS DOMESTIC BREEDS DIFFER IN THEIR SUSCEPTIBILITY TO INFECTIONS AND THEIR IMMUNE RESPONSE AFTER INFECTION GOOD EXAMPLES ARE THE GENETIC RESISTANCE OF SHEEP TO SCRAPIE OR THE GENETIC RESISTANCE TO TRYPANOSOMIASIS OF N’DAMA CATTLE BREED

SUSCEPTIBILITY TO RABIES INFECTION AND VACCINATION WILD AND DOMESTIC SPECIES DIFFER IN THEIR SUSCEPTIBILITY TO A GIVEN RABIES VIRUS STRAIN DOG BREEDS DIFFER DRASTICALLY IN THEIR IMMUNE RESPONSE AFTER VACCINATION AGAINST RABIES AS EXEMPLIFIED BY THE IMPLEMENTATION OF THE UK PET SCHEME

VIRUSES HAVE CO-EVOLVED WITH THEIR NATURAL HOSTS THE PATHOGEN: VIRUSES VIRUSES EVOLVE QUICKER THAN THEIR HOSTS BY: Point mutations Deletions Recombination Reassortment Acquisition of cellular genes VIRUSES HAVE CO-EVOLVED WITH THEIR NATURAL HOSTS

EVOLUTION OF RNAs VIRUSES RNAs VIRUSES EVOLVE VERY QUICKLY LEADING TO QUASI-SPECIES AND CAN THEREFORE ADAPT TO NEW HOST SPECIES

THE EXAMPLE OF FOOT AND MOUTH DISEASE VIRUS (APHTHOVIRUS) DIVERGING VIRUSES (7 SEROTYPES) CAN CAUSE THE SAME DISEASE

HUMAN HERPESVIRIDAE Human herpesvirus 1 Human herpesvirus 2 Human herpesvirus 3 (VZV) Human herpesvirus 4 Human herpesvirus 5 Human herpesvirus 6 Human herpesvirus 7 Human herpesvirus 8

BOVINE HERPESVIRIDAE Bovine herpesvirus 1 Bovine herpesvirus 2 CATTLE IS ALSO SUSCEPTIBLE TO THE INFECTION WITH PSEUDORABIES VIRUS (Suid herpesvirus 1), A DEAD-END INFECTION

THE WORLD OF VIRUSES IS HUGE THERE ARE 5,416 RECOGNISED MAMMAL SPECIES; HERPESVIRUSES HAVE BEEN ISOLATED FROM ALL CLASSES OF VERTEBRATES AND EVEN FROM OYSTERS. THE WORLD OF VIRUSES IS HUGE

MECHANISMS OF EMERGENCE VIRUS MUTATION ( CANINE PARVOVIRUS INFECTION) OPENING THE ECOSYSTEMS CLIMATIC CHANGES INVASIVE SPECIES INTRODUCTION OF NEW SPECIES BIOLOGICAL PRODUCTS THE FIVE Ts

THE FIVE Ts TRANSPORT TRADE TRAVEL TOURISM TERRORISM

THE CASE OF BLUETONGUE IN NORTHERN EUROPE

Clinical bluetongue in cattle: face Muzzle: ulcerous and necrotic lesions, scabs Nose: ulcers in the nostrils, mucous to mucopurulent nasal discharge Oral cavity: ulcers in the gengiva and the tongue, with hypersalivation Peri-ocular oedema and erythema, lacrymation Submandibular swelling

Clinical bluetongue in cattle: limbs and udder Œdema Muscular rigidity Interdigital lesions Lameness Udder Œdema and erythema of udder Ulcers on the teats

BLUETONGUE IN NORTHERN EUROPE A SUB-SAHARAN SEROTYPE (8) A NEW VECTOR NOT KNOWN TO BE COMPETENT BEFORE

NO MORE TWO PARTNERS BUT THREE ONES VECTORIAL DISEASES NO MORE TWO PARTNERS BUT THREE ONES

THE MOST DIFFICULT TO ELIMINATE VECTORIAL DISEASES 2 THE MOST DIFFICULT TO ELIMINATE BY ESSENCE ALL ZOONOTIC DISEASES HAVE A RESERVOIR AND ARE THEREFORE ALSO DIFFICULT TO CONTROL UNLESS ONE CAN ELIMINATE WILDLIFE INFECTION: THE CASE OF TERRESTRIAL RABIES

ERADICATION OF INFECTIONS ONLY TWO INFECTIONS ERADICATED SO FAR: SMALLPOX AND RINDERPEST THEY SHARE THE SAME CHARACTERISTICS

COMING BACK TO RINDERPEST ACCORDING TO FRANK FENNER, TO BE ERADICATED A DISEASE MUST: Be important and serious Absence of sub-clinical infection or silent excretion Absence of contagion during the incubation or prodromic periods Absence of asymptomatic carriers or recurrent access of excretion or disease One virus serotype Seasonal incidence No alternative reservoir THE AVAILABILITY OF AN EFFICACIOUS AND STABLE VACCINE